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[Display omitted] • Wafer-scale high-quality MoSe 2 nanosheets were achieved by ALD-CVD composite process. • High on/off ratio (3.6 × 107) and significant hysteresis window (6.8 k) of MoSe 2 synaptic devices were achieved. • We proposed horizontal diffusion driven mechanism for Se vacancy. Recently, researches have revealed that synaptic transistors based on two-dimensional materials (2DMs) have substantial advantages and potential for modeling neural synapses. However, the mechanism of artificial synaptic device with 2DMs as conducting channels remains to be further clarified. Here, high-quality wafer-scale MoSe 2 nanosheets were achieved by ALD-CVD process, where further 23 × 23 × 4 synaptic arrays were fabricated in situ. Notably, the outstanding MoSe 2 synaptic device exhibits an on/off ratio of 3.6 × 107 with hysteresis ratio of 6.8k and simulates crucial biological synaptic behaviors such as paired pulse facilitation and excitatory postsynaptic currents. The mechanism of Se vacancy induction and horizontal diffusion driven is revealed based on high-resolution transmission electron microscopy characterization with first-principles calculations, which suggests a possible mechanistic explanation for the resistive switching behavior of 2DMs transistors. Artificial synaptic devices with 2DMs based on the working mechanism of vacancy diffusion are capable of satisfying the needs of complex neural network applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Large 2D nanosheets of Bi 2 O 2 CO 3 are synthesized by discharges in liquids. • The growth is driven by the ledge mechanism assisted by ions at the cathode. • The liquid has no influence on the because of the formation of a metallic plasma. • The process is highly reproducible thanks to a chemical etching pretreatment. The growth of Bi 2 O 2 CO 3 nanosheets through nanosecond-pulsed discharges in liquid environments has been achieved by applying voltages slightly above the breakdown voltage. This growth process involves surface modification of the cathode electrode following pretreatment with chemical etching. Remarkably, the choice of liquid medium, whether water or liquid nitrogen, does not significantly affect the interaction between the electrodes and the metallic discharge that forms during the initial stages of synthesis. This process is template-free. The anisotropic growth of these two-dimensional objects is attributed to ion-assisted deposition via the ledge mechanism, supplemented by the presence of surface defects. Prior to the growth treatments, chemical etching is essential to enhance the probability of nanosheet formation from virtually zero to almost a hundred percent. This step is crucial in eliminating native oxide layers and exposing surface defects, which are present as parallel planes forming combs within polishing scratches. The detachment of nanosheets from the cathode and their release into the liquid is facilitated by the sweeping of the liquid-bubble interface, which breaks the nanosheets away from their substrate. As the electrodes undergo aging, nanosheets are formed by outward diffusion of bismuth and reaction with water and CO 2 in the air. By gaining a better understanding of this growth mechanism, exciting opportunities arise for the design and large-scale production of 2D nanostructures. [ABSTRACT FROM AUTHOR]

[Display omitted] • CoS x –graphene were decorated on Ni(OH) 2 nanosheets via electrodeposition process. • CoS x –graphene@Ni(OH) 2 exhibited the evolution of porous nanoplatelets structures. • CoS x –graphene@Ni(OH) 2 exhibited the highest specific capacitance of 1618 F∙g−1 at 1 A∙g−1. • CoS x –graphene@Ni(OH) 2 revealed better cyclic stability than pure Ni(OH) 2 nanosheets. In the present work, binder-free CoS x –graphene nanoplatelets porous structures were coated on Ni(OH) 2 nanosheets using a one-step electrodeposition process. The graphene was produced from the electroreduction of CO 2 ∗ intermediates during the electrodeposition of CoS x. The surface morphology and interfacial bonding states of CoS x –graphene@Ni(OH) 2 were sensitive to the deposition time and Co–to–thiourea molar ratio (M r). The interface reconstruction between CoS x –graphene NCs and Ni(OH) 2 nanosheets improved the pseudocapacitance performance, which was investigated at different M r and varying deposition times. Raman spectra verified the presence of graphene and CoS x mixed phases in all heterostructure electrodes, where CoS 2 was dominant at M r = 0.2. An XPS analysis indicated the evolution of various interfacial bonding states (C O, C O, Co O Ni, and S O) between Ni(OH) 2 nanosheets and CoS x -graphene nanoplatelets, revealing the improvement in the interfacial synergy and concentration of electroactive sites. The hybrid CoS x -graphene@Ni(OH) 2 NCs at M r = 0.2 exhibited the highest capacitance of 2116 F∙g−1 at 2 mV∙s−1 and 1618 F∙g−1 at 1 A∙g−1 compared with bare Ni(OH) 2 , which achieved 1212 F∙g−1 at 2 mV∙s−1 and 882.88 F∙g−1 at 1 A∙g−1, and other NCs. Bare Ni(OH) 2 nanosheets retained only capacitance retention of 25 % after 2000 cycles, which improved to 70 % in all CoS x -graphene@Ni(OH) 2 nanoplatelets. [ABSTRACT FROM AUTHOR]

[Display omitted] • SnO 2 nanorods, nanosheets, and nanoparticles were prepared. • Pd/SnO 2 nanorods exhibited superior activity for CH 4 oxidation. • The critical role of SnO 2 morphology in the catalytic efficiency of Pd/SnO 2 was revealed. • SnO 2 morphology influenced the chemical state of Pd and the reducibility of Pd-O-Sn moieties. Tin dioxide (SnO 2) nanorods, nanosheets, and nanoparticles were synthesized to explore the influence of morphology on the catalytic performance of Pd/SnO 2 in CH 4 oxidation. Among these, Pd/SnO 2 nanorods exhibited superior activity, achieving the earliest onset of methane conversion (T 10% at 227 °C) and complete conversion (T 100% at 400 °C), compared to nanosheets and nanoparticles. The structure–activity study indicates that the nanorod morphology not only enhances the availability of active oxygen species and increases the Pd2+/Pd4+ ratio, but also lowers the reduction temperature of Pd-O-Sn moieties. These features collectively enhance the oxidation of CH 4. This study highlights the critical role of SnO 2 morphology in optimizing the catalytic efficiency of Pd/SnO 2 , providing valuable insights for designing catalysts aimed at low-concentration CH 4 oxidation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Lamellar Mo 2 C/C-rGO was fabricated by freeze-casting and subsequently carbothermal reaction. • Mo 2 C/C nanoclusters were in situ induced from PPy/PMo 12 nanospheres. • Abundant interfaces in Mo 2 C/C-rGO endow the excellent EM wave absorption performance at a low filling ratio of 5 wt%. • The minimum RL was −49.3 dB at 1.38 mm and the EAB (RL<-10 dB) was 5.12 GHz at 1.60 mm. It is an effective strategy that constructing composites with a multi-dimensional structure synergistically enhance their electromagnetic (EM) wave absorbing performance. Herein, a high-efficiency EM wave absorber of Mo 2 C/C nanoclusters uniformly encapsulated in rGO nanosheets (Mo 2 C/C-rGO) was prepared by a combination of the directing freeze-dry and subsequently carbothermal reaction method. Mo 2 C/C was in-situ induced from spherical phosphomolybdic acid/polypyrrole (PMo 12 /PPy) to result in a unique cluster-like microstructure. Abundant heterogeneous interfaces endowed the Mo 2 C/C-rGO composites with excellent EM wave absorption performance at a low filling ratio of 5 wt%. The minimum reflection loss (RL) value was −49.3 dB at 1.38 mm and the maximum effective absorption bandwidth (EAB, RL<-10 dB) was 5.12 GHz at 1.60 mm. The excellent performance was owing to the lamellar structure and abundant heterogeneous interfaces in Mo 2 C/C-rGO, lengthening the transmission path of the incident wave, as well as resulting in high conduction loss and interfacial polarization loss. This universal strategy would be extended to other absorbers with multi-interface structures for lightweight and broadband EM wave absorption. [ABSTRACT FROM AUTHOR]

[Display omitted] • A tree-inspired semiconductor-on-ceramic 2D/1D heterostructure. • Vertical alignment of silicate nanosheets on hydroxyapatite nanowires. • Hierarchical structure enhances CO 2 adsorption and charge transfer. • Highly efficient CO 2 photoreduction into CO. Two-dimension nanosheets are ideal photocatalysts for CO 2 reduction due to their high exposure of active sites and short charge transfer pathway. However, 2D photocatalysts have a tendency to agglomeration, thus compromising the performance of photocatalytic CO 2 reduction. Trees, one of the most important plants for photosynthesis, have a unique "leaf-on-branch" structure. This unique two-dimension/one-dimension (2D/1D) configuration maximizes the adsorption of CO 2 molecules and light harvesting. Herein, a tree-inspired semiconductor-on-ceramic 2D/1D heterostructure for efficient photocatalytic CO 2 reduction is reported. The cobalt silicate (CoSi) nanosheets (∼0.68 nm) are in situ grown on the surfaces of hydroxyapatite (HAP) nanowires, creating a well-defined 2D/1D hierarchical structure. The vertical alignment of ultrathin CoSi nanosheets on the HAP nanowires effectively suppresses their agglomeration, leading to a large BET surface area (106.45 m2/g) and excellent CO 2 adsorption (8.00 cm3 g−1). The results of photoelectrochemical characterization demonstrate that the 2D/1D hierarchical structure is powerful to expedite charge transfer. As a result, the gas generation rate of CO is as high as 28780 μmol g−1 h−1 over the CoSi-on-HAP 2D/1D heterostructure. In addition, the electron transfer mechanism and reaction pathways of CO 2 reduction are revealed by in situ irradiated XPS and in situ DRIFT spectra. [ABSTRACT FROM AUTHOR]

[Display omitted] • The impact of varied oxygen group localization on electromagnetic shielding properties is investigated. • Coatings with Basal-Functionalized Graphene Oxide (B-GO) nanosheets exhibited superior dielectric properties compared to Edge-Functionalized Graphene Oxide (E-GO) nanosheets. • Enhanced dispersion of graphene nanosheets improved interphase formation, improving dielectric permittivity and interfacial polarization. • Coatings incorporating B-GO nanosheets demonstrate a superior capacity for electromagnetic wave attenuation, attributed to enhanced polarization and conductivity. In this study, two distinct graphene nanosheets, featuring varying localization of oxygen groups, were synthesized to investigate their influence on the electromagnetic waves' absorption properties of polymeric coatings. Natural graphite flakes and expanded graphite served as carbon precursors for synthesizing Edge-Functionalized Graphene Oxide (E-GO) and Basal-Functionalized Graphene Oxide (B-GO) nanosheets, respectively. Subsequently, polymer nanocomposite coatings were fabricated by dispersing E-GO and B-GO into a waterborne epoxy matrix. The dielectric properties of these coatings were measured post-in-situ thermal reduction at 225 °C. Results revealed that coatings containing B-GO nanosheets exhibited higher dielectric values compared to those with E-GO nanosheets. Furthermore, the electromagnetic properties of the coatings were examined to correlate the network formation findings obtained from dielectric studies and reflection loss values. It was demonstrated that an improved dispersion state of graphene nanosheets resulted in enhanced interphase formation between epoxy and graphene nanosheets, thereby improving interfacial polarization and dielectric permittivity values. Additionally, residual oxygen groups situated on the graphene basal plane induced dipolar polarization, consequently enhancing the reflection loss values of electromagnetic waves. Ultimately, the enhancements in electrical conductivity and dielectric permittivity contributed to reflection loss values reaching −52.67 dB in coatings with a thickness of 320 μm and a graphene loading level of 1.5 wt%, representing significant advancements compared to existing literature. [ABSTRACT FROM AUTHOR]

[Display omitted] • Sn-PdPt/TiO 2 with strong metal-MOS interactions was successfully prepared. • Sn-PdPt/TiO 2 sensor exhibited excellent CO and H 2 sensing performance at 200 °C. • The sensitization mechanism of PdPt bimetals on TiO 2 has been proposed. The catalyst with strong metal-support interactions often exhibits high catalytic activity. This study aims to prepare sensitive materials with strong metal-MOS interactions and explore their sensitization mechanism. Sn-PdPt/TiO 2 was obtained by in-situ decorating PdPt bimetals on the surface of TiO 2 NSs using Sn2+ as the reducing agent, and PdPt/TiO 2 was prepared by traditional reduction method. Compared with TiO 2 sensor, PdPt/TiO 2 and Sn-PdPt/TiO 2 sensors exhibited higher sensitivity, selectivity, lower operating temperature (200 °C) and detection limit (ppb level) to CO and H 2. The sensitization of PdPt bimetal to TiO 2 should be ascribed to the high catalytic activity of PdPt bimetal towards O 2 , H 2 and CO, Schottky barrier at the interface between TiO 2 and PdPt NPs, and the multiple valence states (Pd0, Pd2+ and Pd4+) of Pd will undergo mutual transformation during gas sensing reactions. And Sn-PdPt/TiO 2 sensor exhibited higher sensitivity, selectivity and better stability than those of PdPt/TiO 2 sensor, which can be attributed to the introduction of SnO 2 and the stronger interaction between PdPt and TiO 2 due to the in-situ reduction reaction. This study can provide some reference for preparing the MOS based gas sensing materials with strong metal-support interactions and understanding the sensitization mechanism of PdPt bimetal. [ABSTRACT FROM AUTHOR]

[Display omitted] • 3D porous carbons were synthesized by one-step process of organic salts carbonization. • 3D porous carbon exhibited effective physical barrier for sulfur host. • N-doped 3D porous carbon showed improved chemical interactions with LiPSs. • 3D porous carbon materials were applied into sulfur cathode and functional separator. • All-integrated cell exhibited synergetic effects for impeding of LiPSs diffusion. Lithium-sulfur(Li-S) batteries show high theoretical capacity and energy density compared to lithium-ion batteries(LIBs), which are one of the candidates for next-generation energy storage systems. However, rapid capacity fading caused by polysulfide shuttling effects remains critical issue for the commercial development in the Li-S batteries. Therefore, we aimed to derive 3D porous carbon nanosheets(C900) through the simple carbonization of organic salts as base materials for application as both sulfur host and functional separator. C900 had 3D vertically aligned and hierarchical carbon nanosheet structure with a high specific surface area and large pore volume, which was benefits for sulfur hosts because of the efficient electrolyte diffusion pathways and high mass loading of sulfur. Furthermore, nitrogen doped C900(NC900) can be improved chemical reactions with lithium polysulfides. Subsequently, an integrated electrode composed of a cathode with C900 and functional separator with NC900, respectively, was found to be highly efficient in restraining the shuttle effect via multimodal capturing effects. Consequently, all-integrated electrode composed of S-C900 and NC900@PP delivered a high initial specific capacity of 1453mAh·g-1 at 0.1C and achieved cycle stability with 64% capacity retention after 300cycles at 0.5C. This work suggests a potential carbon material design for bi-functional materials in a high-performance Li-S batteries. [ABSTRACT FROM AUTHOR]

[Display omitted] • Composites with Pd nanocrystals and metal hydroxide nanosheets are developed for EOR. • Interfacial effects between Pd facets and nanosheets are systematically investigated. • Adsorption of OH− are promoted at the interface, enhancing activities. • The Pd (1 1 1) facet with MnNi hydroxide emerges as the excellent EOR electrocatalyst. The design of catalyst surfaces that exhibit high activities for ethanol oxidation reaction (EOR) is essential to achieving practical application of direct ethanol fuel cells. Composite catalysts of Pd nanoparticles and metal hydroxide are promising candidates for EOR; however, a guide of catalyst design, including appropriate valence states and interfacial structures between component materials, has not been identified. Herein, we synthesize composite electrocatalysts of cubic and octahedral Pd nanocrystals with well-defined facets and monolayer metal hydroxide nanosheets with an identical structure and different composition containing Ni, Fe and Mn, and systematically elucidate highly active interfacial sites between Pd and metal hydroxides for EOR. Promotion of OH− adsorption by the hydroxide nanosheets enhances the catalytic activities of the Pd nanocrystals and the nanosheet having higher affinity to OH− result in higher EOR performances of the composite catalysts. The improved activities are greater for (1 1 1) facet than for (1 0 0) facet of the Pd whereas the (1 0 0) facet is superior for EOR to the (1 1 1) facet for the bare Pd nanocrystals. Our study suggests that combination of the Pd (1 1 1) facet and metal hydroxides is favorable for developing highly active electrocatalysts for EOR. [ABSTRACT FROM AUTHOR]

[Display omitted] • Co(OH) 2 confined in MIL-100 nanosheets is prepared. • Cobalt acetate colloid is adopted to realize confinement of Co(OH) 2. • Oxygen vacancies are induced by the incorporation of Co(OH) 2. • The nanointerface interaction of Co(OH) 2 /MIL-100 regulates the electronic structure of Fe atoms. • Co(OH) 2 /MIL-100 exhibits superior water splitting activity with the overpotential of 1.62 V. Exploring cost-effective and advanced bifunctional electrocatalysts is crucial for overall water splitting. Confinement engineering integrates electronic structure and interface transfer for synergistic cooperation between active sites and carriers, thus realizing enhanced electrocatalytic performance. Herein, Co(OH) 2 confined MIL-100 nanosheets are grown on nickel foam (Co(OH) 2 /MIL-100) by cobalt acetate colloid. The confinement effect guarantees the highly dispersed Co(OH) 2 in MIL-100. The two-dimensional nanosheet arrays of Co(OH) 2 /MIL-100 provide sufficient active sites and rich channels for facilitated ion/electron transportation. The characterizations and theoretical calculation prove that the strong coupling between Co(OH) 2 and MIL-100 induces oxygen vacancies and highly active Fe3+ species to promote charge transfer and regulate the d-band center. As a result, the intermediate adsorption strength is optimized, which is beneficial to boost the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) process. The Co(OH) 2 /MIL-100 exhibits competitive OER and HER overpotentials of 260 mV and 160 mV at 50 mA cm−2 in alkaline electrolyte, respectively. Furthermore, the two-electrode electrolyzer equipped with Co(OH) 2 /MIL-100(+) || Co(OH) 2 /MIL-100(-) displays a low operation potential of 1.62 V (50 mA cm−2) and maintains high stability for 20 h. Thus, this work offers a novel colloid-assisted confinement strategy to simultaneously tailor the electronic structure and active sites for highly efficient electrocatalysts. [ABSTRACT FROM AUTHOR]

[Display omitted] • Oxygen-deficiency-induced 2D Na y WO 4-x ·2H 2 O label-free fluorescence nanosensor was fabricated for DA detection. • The DA is readily adsorbed by oxygen vacancy and fluorescence is quenched by electron transfer. • DA was quantified with a low detection limit of 0.31 nM with excellent selectivity. • The sensor performance was evaluated in a biological fluid (human serum) with results of R2 value of 0.995. Oxygen-deficiency induced fluorescence nanosensor (ODIFN) method applied in the Two-Dimensional nanosheets has been demonstrated in this paper. In this approach, we synthesized the abundant oxygen-deficient Two-Dimensional (2D) Na y WO 4-x ·2H 2 O nanosheets fluorescence sensors and applied them for highly sensitive and selective dopamine detection. Researchers have been intensively motivated to create novel nanomaterials that enable the effective detection of dopamine (DA) in clinical samples. DA is a significant biomarker for various brain-related diseases such as Parkinson's disease. We developed 2D Na y WO 4-x ·2H 2 O nanosheets that exhibited a stable fluorescence emission at λ em 360 nm. The non-stochiometric Na presenting in 2D nanosheets acts as a defecting agent for oxygen deficiency that results in strong and stable fluorescence. The fabricated fluorescence nanosheets were exhibited for the detection of dopamine with high sensitivity and selectivity. The ODIFN demonstrated a linear range of detection from 50 nM to 2 µM with a limit of detection of 0.31 nM and a very high R2 value of 0.996. Moreover, the sensor performance was evaluated in a biological fluid (blood serum) with results of R2 value of 0.995, which proves the high potential of Na y WO 4-x ·2H 2 O nanosheets in DA sensing. The ODIFN via the 2D Na y WO 4-x ·2H 2 O fluorescent sensor is a novel platform for producing artificial fluorescence that can be widely applied in all fields such as medical, biological, and life science fields to replace the traditional dyes that are highly harmful to environments. [ABSTRACT FROM AUTHOR]

[Display omitted] • The combined incorporation of h-BN nanosheets and low-melting nanoclays in PEO is explored. • h-BN nanosheets are effectively incorporated into PEO in the presence of nanoclays. • Surface features, wettability, mechanical properties, bonding strength and corrosion resistance are studied. • In-situ incorporated stannate provided added active corrosion protection. Boron nitride nanosheets and organo-modified nanoclays are in-situ incorporated into the plasma electrolytic oxidation (PEO) layer fabricated on AZ31B Mg alloy. A stannate-based corrosion inhibitor with an inherent self-repairing effect is also tested. The modified PEO/Mg alloys are characterized for micro/nano-scale surface morphology and roughness, phase and microstructure, elemental composition and distribution, surface wettability and are studied for mechanical properties, bonding strength and electrochemical corrosion resistance. The results suggested fruitful benefits of the combined in-situ incorporation on PEO/Mg alloy's corrosion resistance. The hard ceramic nanomaterials with high melting points, such as boron nitride, could be more effectively incorporated into the PEO layer with the co-deposition of low-melting nanoclays. Besides, an inhibitor such as stannate in the PEO deposition bath could make an effective protective conversion layer, providing an additional protective effect without significantly interfering with the PEO layer formation. The results provided could be beneficial in developing better PEO/Mg alloys for industrial applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • The synergistic effects arising from the components in composite microgels were found. • Friction and wear behavior under the microgel lubrication were evaluated. • The corresponding surface lubrication mechanism were illuminated. In this investigation, the surface tribological behavior of YG8/TC4 contacts under microgel lubrication was explored, utilizing thermal- and pH-sensitive PNIPAM-co-PAA-(IF-MoS 2 /GO) composite microgels as lubricant additives. Through the application of a ball-on-disk reciprocating tribometer, the study demonstrated the outstanding lubrication capabilities of the composite microgels. The lubrication process involving PNIPAM-co-PAA-(IF-MoS 2 /GO) composite microgels initiated a tribo-chemical reaction, leading to the generation of a larger quantity of TiS 2 with exceptional lubricating properties on the friction surface compared to alternative lubrication conditions. The effective isolation of the friction pair by PNIPAM-co-PAA composite microgels contributed to the reduction in tribo-oxidation of the sliding surfaces , while the presence of IF-MoS 2 facilitated the formation of TiS 2. Furthermore, the facile sliding property of GO nanosheets played a crucial role in achieving overall excellent lubrication performance. The synergistic effects arising from the components in PNIPAM-co-PAA-(IF-MoS 2 /GO) composite microgels introduce a novel and effective strategy for controlling the friction and wear of YG8/TC4 contacts. [ABSTRACT FROM AUTHOR]

Here, a Cs 3 Bi 2 Br 9 conversion strategy is proposed to fabricate BiOBr nanosheets with highly exposed (001) facets. The width and thickness of BiOBr nanosheets can be precisely modulated by controlling the amount of Cs during synthesis. This facile approach facilitated the synthesis of an ohmic MXene/BiOBr heterojunction, significantly enhancing the separation of photogenerated carriers. [Display omitted] • Perovskite conversion strategy is proposed to fabricate BiOBr nanosheets. • BiOBr nanosheets with highly exposed (001) facets were successfully synthesized. • The width and thickness of BiOBr nanosheets can be precisely modulated by controlling the amount of Cs during synthesis. • An ohmic MXene/BiOBr heterojunction was fabricated. • This ohmic heterojunction exhibited complete photodegradation of rhodamine B within 7.5 min of light irradiation. BiOBr has garnered significant attention for photocatalysis owing to its distinctive layered structure. Nevertheless, it is full of challenges to synthesize high-quality BiOBr nanosheets by a simple room-temperature strategy due to the rapid chemical reaction between (Bi 2 O 2)2+ cations and Br- anions. Herein, a Cs 3 Bi 2 Br 9 conversion strategy is proposed to fabricate BiOBr nanosheets with highly exposed (001) facets. BiOBr nanoclusters can grow on the surface of Cs 3 Bi 2 Br 9 during the hydrolysis process, which can prevent further corrosion of Cs 3 Bi 2 Br 9 , resulting in a sluggish BiOBr formation rate. During the conversion process, atom rearrangement occurs, leading to the creation of abundant oxygen vacancies. Furthermore, through precise adjustment of the amount of Cs, we can finely modulate the width and thickness of BiOBr nanosheets. As a result, the optimal sample achieves complete photodegradation of rhodamine B under 12.5 min of light irradiation. Utilizing this facile and convenient preparation method, an ohmic heterojunction comprising MXene and BiOBr has been synthesized, effectively promoting the separation of photogenerated carriers. Excitingly, the fabricated BiOBr/MXene exhibits higher photocatalytic efficiency than the single BiOBr, which can degrade rhodamine B within 7.5 min. [ABSTRACT FROM AUTHOR]

[Display omitted] • A previously unreported binary ZnO@MgAl-LDH composite photocatalyst was developed via the hydrothermal method. • The ZnO@MgAl-LDH composite was converted from Type I to Type II by introducing Al doping into the ZnO component. • The ZnO@MgAl-LDH composite's photocatalytic performance was notably enhanced by modifying its band structure. The ZnO hollow nanospheres were initially prepared using the template method. Subsequently, MgAl-LDH nanosheets were in-situ grown on the surface of the nanospheres via the hydrothermal method, resulting in the synthesis of a type-I heterojunction-based ZnO@MgAl-LDH composite photocatalyst. However, the introduction of Al dopant into the ZnO hollow nanosphere component resulted in an elevation of the Fermi level of ZnO, which led to a change in the heterojunction type in the ZnO@MgAl-LDH composite from type-I to type-II. Consequently, the separation of photo-generated carriers in the Al-doped ZnO@MgAl-LDH composite was significantly enhanced, thereby improving its photocatalytic performance. Moreover, the mass ratio of Al-doped ZnO hollow nanospheres and MgAl-LDH was examined in greater detail to ascertain its influence on the photocatalytic performance of the composite photocatalyst. All Al-doped ZnO@MgAl-LDH composite samples exhibited enhanced photocatalytic performance in comparison to the composite sample without Al doping. Furthermore, when the mass of Al-doped ZnO hollow nanospheres was maintained at 0.100 g and the Mg2+ concentration in the precursor was 0.006530 mol/L, the resulting Al-doped ZnO@MgAl-LDH composite sample demonstrated the most optimal photocatalytic performance among all the investigated samples. [ABSTRACT FROM AUTHOR]

The tannic acid induced assembly strategy was used to synthesize the Ni-doped SnO 2 nanosheets. The fabricated TA-Ni/SnO 2 sensors exhibited superior sensing performance to HCHO at working temperature of 80 °C (R a /R g = 184.3) and excellent sensing selectivity. The experimental and DFT results illustrated that the highly dispersed Ni substitution sites in SnO 2 crystals can be regarded as the active sites, which not only facilitated the generation of surface active O 2 –(ad) species, but also modified the electronic structure of SnO 2 crystals, contributing to superior sensing performance of TA-Ni/SnO 2 to HCHO. [Display omitted] • Tannic acid (TA) induced surface functional strategy is applied to synthesize Ni-doped SnO 2 nanosheets. • Ni ions can be highly dispersed on the SnO 2 nanosheets via TA. • The obtained materials exhibit superior sensing performance to HCHO. • The synergistic effects between O 2 –(ad) species and modified electronic structure contribute to the excellent sensing performance. Surface functionalization is a promising strategy to modulate the electronic and surface properties of metal oxide semiconductors. Here, we report a tannic acid (TA) induced surface functional strategy to synthesize Ni-doped SnO 2 nanosheets. Benefiting from the abundant polyphenolic and catechol groups, the linkage of TA not only exhibit high affinity to various substrate, but also show powerful chelating ability to metal ions. Hence, Ni ions can be highly dispersed on the SnO 2 nanosheets via TA, TA linkage also can prevent the aggregation of Ni ions during pyrolysis, and Ni substitution in SnO 2 crystals can be obtained. As a proof-of-concept demonstration, the TA-Ni/SnO 2 sensor is fabricated to detect HCHO, and exhibit superior sensing performance at low working temperature of 80 °C (R a /R g = 184.3), excellent sensing selectivity and long-term stability. Detail experimental and theoretical calculation demonstrate the highly dispersed Ni substitution active sites facilitate the generation of surface O 2 –(ad) species, and the electronic structure also can be modulated to exhibit high affinity to HCHO, hence, the synergistic effects contribute to the enhanced sensing performance. Our work paves the way for versatile surface functionalization to synthesize advanced materials for application in catalysis and sensing field. [ABSTRACT FROM AUTHOR]

[Display omitted] • The effects of different micro-configuration of GO on the interfacial adhesion are studied. • The interface adhesion of CFRPs is precisely adjusted by regulating the mass ratio of CF to GO. • The "Upright" distribution of moderate-sized GO generates a wider, modulus gradient change interface. • Interface failure mode and performance enhancement mechanism are synthetically investigated. Different micro-configurations of graphene oxide (GO) nanosheets on the carbon fiber (CF) surface, including the distribution and size, endow CF-GO enhanced microstructure and physiochemical characteristics of the CF/epoxy (CF/EP) composites. In order to investigate the relationship between the GO micro-configuration and the interfacial adhesion of the CF/EP, here, polyether imide (PEI)-GO heterogeneous reinforcement was grafted onto the CF surface (CF-PEI-GO) by precisely modulating the mass ratio of CFs to GO. The micro-configuration and properties of the CF-PEI-GO hybrids, together with the thickness and modulus variation of the interface layer are investigated, in order to make certain on the enhancement mechanisms of both interfacial and mechanical performances. Optimal performances of the CF-PEI-GO/EP composites are achieved with a CF/GO mass ratio of 40:1. The uniformly "upright" distribution of moderate-size GO on the CF surface induces a synergistic effect of improved mechanical interlocking, chemical bonding, high wettability, and effective interface adhesion, which are stemmed from higher surface roughness, more active functional groups, higher surface energy, and wider interface thickness with gradient descent modulus. This work presents a valid, practical strategy to precisely control the interfacial adhesion of the CF/EP composites by adjusting the micro-configuration of 2D materials on the fiber surface. [ABSTRACT FROM AUTHOR]

[Display omitted] • A hybrid of Mo-WN coated with carbon shell and Co(OH) 2 is constructed successfully. • The hybrid shows the small η 100 of 148 mV and η 500 of 196 mV. • Co(OH) 2 and Mo doping endow the hybrid with an appropriate water dissociation energy. • Free energy diagram reveals Co(OH) 2 and Mo doping promote Volmer and Heyrovsky steps. Water electrolysis is currently the most important way to achieve large-scale hydrogen (H 2) production. Although many nonprecious electrocatalysts possess promising catalytic performance at low current density below 50 mA cm−2, it remains a substantial challenge to realize H 2 production at industry-compatible current density over 500 mA cm−2. Here we have designed a hierarchical heterostructure of molybdenum-doped tungsten nitride coated with carbon shell and cobalt hydroxide nanosheets (Mo-WN@NC@Co(OH) 2) for alkaline hydrogen evolution reaction (HER) with industrial current density and stability. The hybrid exhibits efficient alkaline HER activity, reaching the current density of 500 mA cm−2 at an overpotential of 196 mV. The Co(OH) 2 nanosheets and Mo doping endow the composite with more active sites and enhanced intrinsic activity of the catalyst, as well as an appropriate water dissociation energy. In addition, the free energy of activation for each step during the HER process suggests a synergistic effect of Mo doping and Co(OH) 2 in Mo-WN@NC@Co(OH) 2 promoting surface Volmer and Heyrovsky steps during the HER process. This doping and interfacial engineering methods hold great promise for fabricating efficient nitride-based electrocatalysts for electrochemical energy devices. [ABSTRACT FROM AUTHOR]

The Bi/Bi 2 O 2 CO 3 composite films anchored on Bi substrates is in situ constructed via electrochemical and hydrothermal-ion-exchange metho and exhibits excellent activity and long-term stability for photoelectrocatalytic CO 2 reduction to formate. [Display omitted] • In-situ construction of Bi/Bi 2 O 2 CO 3 nanosheets anchored on Bi substrate as working electrode film. • Outstanding selectivity of photoelectrocatalytic CO 2 reduction to formate. • There are uniform distribution of active sites and dynamic regeneration ability. • The formation and photoelectrocatalytic CO 2 reduction mechanisms are proposed. Utilizing photoelectrocatalysis for the CO 2 conversion into value-added chemicals presents a promising approach for alleviating energy-environmental crisis, but the current catalysts encounter the limitations of electron transfer efficiency, activity and stability. Herein, we in situ construct Bi/Bi 2 O 2 CO 3 composite film with nanosheets anchored on Bi substrate to optimize reaction kinetics, and effectively enhance the separation and transport efficiencies of photogenerated carriers. Our findings reveal that the formate Faraday efficiency of 92.68 % at −0.95 V (vs. RHE) for photoelectrocatalytic CO 2 reduction over Bi/Bi 2 O 2 CO 3 film is much higher obviously than 84 % of electrocatalytic CO 2 reduction reaches, and there is no significant decrease within 10 h of activity test. Besides, the highest applied bias photon-to-current efficiency and cathode energy efficiency can achieve 1.19 % and 61 %, respectively, indicating the superior energy utilization of the catalyst. Finally, a reasonable electron transfer mechanism for the enhanced photoelectrocatalytic CO 2 reduction over Bi/Bi 2 O 2 CO 3 film is proposed and clarified based on the spectral characterizations and density functional theory calculations. This work should provide a novel perspective for the design and research of Bi-based photocathodes. [ABSTRACT FROM AUTHOR]

The InZrO x nanosheets had peculiar structure and plenty of oxygen defects, and displayed eminent performance in methanol synthesis from CO 2 and H 2. [Display omitted] • Two-dimensional InZrO x nanosheets were synthesized via a simple solvothermal method. • The InZrO x nanosheets had peculiar structure and plenty of oxygen defects. • The optimized ZrO 2 (30)-In 2 O 3 nanosheets showed ∼ 90 % methanol selectivity and an activity of 1.4 mmol g In -1h−1 at 180 °C. • Water as a clean solvent participated in the kinetic process of the reaction.. Synthesis of methanol via CO 2 hydrogenation is a very important reaction. In recent years, the In 2 O 3 based catalysts were proved to be a sort of promising catalysts to accelerate this reaction, which have aroused extensive attention. However, design of novel In 2 O 3 based catalysts that can efficiently produce methanol from CO 2 hydrogenation at low temperature is still in great need. Herein we fabricated the InZrO x nanosheets via a simple solvothermal method, which had peculiar surface structure and plenty of oxygen defects. The InZrO x nanosheets displayed excellent low temperature catalytic performance in a slurry reactor. The methanol selectivity (90 %) and activity (1.4 mmol g In -1h−1) were achieved at 180 °C, which are 2.3 and 1.6 times than that of the counterpart nanoparticles, respectively. Water as a clean and cheap reaction solvent played a crucial role, which participated in the kinetic process of the catalysis. The particular catalyst structure and the solvent effect of water accounting for the outstanding reaction results. [ABSTRACT FROM AUTHOR]

[Display omitted] • Graphene oxide (GO) nanosheets are used on steel surfaces to realize macroscopic superlubricity with electric stimulation. • GO adsorption film's morphology on the intermittent contact surface is the main factor affecting lubricating performances. • This study lays a foundation for superlubricity applications in electrical environments in engineering contexts. Achieving macroscopic superlubricity in electric environments on steel surfaces remains a challenge. This study achieved macroscopic superlubricity on steel surfaces by employing graphene oxide (GO) nanosheet additives with electric stimulation. Multiple factors were studied regarding the effect on lubrication performances. The morphology of the GO adsorption film on the intermittent contact surface (disc) is the main factor affecting the COF, as the continuous contact surface (ball) is required to overcome the peaks of GO film during sliding. The mechanism underlying the friction reduction is concluded as follows: when the intermittent contact surface (disc) was the positive pole, negatively charged GO migrated towards it, forming an adsorption film on its surface. The surface layer orientation of the GO film is relatively smooth, attributed to its contact with the negative pole (ball), resulting in friction reduction. This study illustrates the feasibility of achieving macroscopic superlubricity on steel interfaces through electric stimulation, thereby laying the groundwork for practical applications of superlubricity in engineering contexts, particularly in electric environments. [ABSTRACT FROM AUTHOR]

[Display omitted] • A ultrasonication probe method was synthesized fluorescent 2D MgS nanosheets. • Hexagonal 2D MgS nanosheets were blueish green fluorescent obtained. • Fluorescent 2D MgS NS was quenched in the detection of ferritin. We have developed a highly sensitive and selective ferritin biosensor using the two dimensional (2D) fluorescent Magnesium Sulfide (MgS) nanosheets (NS) using ultra-sonication probe method. Ferritin (Fe3+) is spherical iron containing blood protein which acts as a storage house for iron. This Fe3+ protein is an important biomarker for the detection of iron deficiency (anemia) such as, oxidative stress and cancer. Ultrasonication probe with one pot stirring method to synthesizethe 2D MgS NS was physicochemical, morphological, and analytical studied. The greenish-blue fluorescence of synthesized 2D MgS NS was optimized with maximum intensity at the excitation wavelength of 370 nm and emission wavelength of 435 nm. The quantum yield was 52.6 % found for fluorescent 2D MgS NS. The key role of 1-methylimidazole revealed 2D hexagonal nanosheets with high stability of fluorescence. Besides, the greenish-blue fluorescence of the proposed material was well quenched with the addition of Fe3+, resulting in a linear upward trend in the Stern-Volmer plot owing to static quenching. Further, the selectivity analysis of novel MgS NS shows an excellent selectivity for Fe3+ in the presence of other analytes showing 77 % quenching efficiency and LOD 9 nM with a wide linear range of 10 to 200 nM for Fe3+ detection. The proposed biosensor was successfully employed to detect Fe3+ in blood serum samples with excellent linearity and applicability in clinical diagnosis. [ABSTRACT FROM AUTHOR]

[Display omitted] • Oxygen vacancies modulated BiOBr nanosheets was prepared by the treatment of NaBH 4. • The electron density around Bi atoms near the oxygen vacancies could increase after the construction of oxygen vacancies. • The accelerated separation of photogenerated charge boosts CO 2 and Cr(VI) photoreduction. Unsatisfactory charge separation ability and insufficient active sites are the main factors leading to low efficiency for photocatalytic CO 2 conversion and Cr(VI) reduction. Constructing surface defects to accelerate charge separation is an effective strategy for promoting photocatalytic process. Herein, the oxygen vacancies modulated BiOBr nanosheets were constructed by NaBH 4 solution treatment. Density functional theory calculation results found that the formed oxygen vacancies would increase the electron density around Bi atoms near the oxygen vacancies, and inhibiting recombination of the photoinduced carriers. Besides, abundant oxygen vacancies can effectively enhance the adsorption of CO 2 molecules. Therefore, the BiOBr with rich oxygen vacancies (BiOBr-ROV) shows higher evolution rates for CO (15.66 μmol g−1) and CH 4 (0.22 μmol g−1) under irradiation of 300 W Xe lamp for 4 h compared with pristine BiOBr nanosheets (BiOBr) and BiOBr with deficient oxygen vacancies (BiOBr-DOV). The intermediate products in the CO 2 reduction process have been detected by in-situ Fourier-transform infrared spectroscopy. Besides, the photodegradation activity of Cr(VI) over BiOBr-ROV is 98.65% under 80 min of irradiation, which is higher than that of BiOBr (78.01%) and BiOBr-DOV (53.67%). The work provides a new possibility to construct photocatalysts with high-performance for solar energy conversion. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ultrathin PdAg/PtPdAg P-NSs containing highly porous edges were synthesized under mild reduction conditions without strong surface-binding stabilizers. • The morphology evolution of the PdAg/PtPdAg P-NSs was investigated. • Adsorption properties of intermediates formed during EOR on the PdAg/PtPdAg P-NSs were investigated. • The PdAg/PtPdAg P-NSs exhibited electrocatalytic activity 6.6 times greater than that of commercial Pd/C for EOR. • The enhanced EOR performance of PdAg/PtPdAg P-NSs is attributed to high atom utilization efficiency, undercoordinated atoms at the porous edges, and optimized electronic structure and oxophilic property. Ultrathin metal alloy nanosheets offer promising applications in electrocatalysis due to their superior performance. In this study, we present a rational synthesis of ternary alloy ultrathin PdAg/PtPdAg nanosheets possessing highly porous edges (PdAg/PtPdAg P-NSs). By adopting mild reduction conditions and eliminating the need for strong surface-binding stabilizers, we effectively suppressed 3D growth and stabilized the unstable edges, resulting in ultrathin nanosheets with highly porous features. Importantly, these PdAg/PtPdAg P-NSs demonstrate remarkable electrocatalytic performances for the ethanol oxidation reaction, outperforming both their ternary counterparts and commercial Pd/C catalysts. This innovative synthetic approach offers a pathway to the design of high-performance 2D electrocatalysts for a broad spectrum of applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • LASiS is used synthesize magnetic nanomaterials for biomedical applications. • LASiS under acetone resulted in Fe@Fe 2 O 3 core-shell NPs with maghemite (γ-Fe 2 O 3). • LASiS under toluene resulted in Fe 3 C@C core-shell NPs coated by glassy C shells. • LASiS under heated toluene increases Fe 3 C@C NPs coated by graphitic C shells. • Mossbauer spectroscopy revealed the magnetic properties of the synthesized NPs. Magnetic nanostructured materials (MNMs) have gained prominence in materials technology developments owing to their potential biomedical applications for hyperthermia cancer treatment, and transplant organ cryopreservation. Herein, we report the facile and cost-effective synthesis of Fe-based composite MNMs, comprising both Fe@Fe 2 O 3 and Fe 3 C@C core-shell nanoparticles (NPs), via Laser Ablation Synthesis in Solution (LASiS) using Fe targets ablated under acetone and toluene. Detailed materials characterizations using electron microscopy-based imaging, diffraction studies, and spectroscopic analyses - including Raman and Mössbauer spectroscopy - relate the structure-composition properties for different Fe-oxide/carbide phases in the aforesaid MNMs to their respective magnetic responses. Specifically, we confirm the presence of ultra-small (2–10 nm) amorphous Fe-oxide NPs, as well as Fe@Fe 2 O 3 core-shell NPs (20–40 nm) in the samples synthesized by ablating Fe under acetone. In contrast, samples synthesized under toluene indicate a higher concentration of Fe 3 C@C core-shell NPs (20–40 nm) with a relatively low concentration of Fe 2 O 3 NPs (2–10 nm). Furthermore, the crystallinity of the metallic phases and carbonaceous shell coatings are systematically increased by carrying out LASiS under heated toluene (up to ∼95 °C). Mössbauer spectroscopy results indicate that the elevation in toluene temperature leads to an increase in the concentrations of Fe 3 C@C NPs from ∼40 % to ∼53 % (at.). [ABSTRACT FROM AUTHOR]

[Display omitted] • We selected the antifouling carbon nanomaterials for PPF monitoring through DFT calculations and experiments. • For the first time, the antifouling ability of different carbon nanomaterials on PPF oxidation products were compared. • The ranking of critical factors for antifouling performance was hydrophilicity > geometric morphology > active surface area. • We propose a mechanism-driven approach to design a highly sensitive and durable biosensor for point-of-care PPF monitoring. Carbon nanomaterials, renowned for their exceptional sensitivity and selectivity towards various medical drugs, hold promise as electrode materials for electrochemical biosensors in propofol (PPF) monitoring. However, the issue of fouling has hindered their effective utilization in continuous point-of-care monitoring. In this research, we present a mechanism-driven approach to design a highly sensitive and durable electrochemical sensor tailored for PPF monitoring. We investigated the antifouling mechanism through density functional theory calculations and experiments and found that carboxyl functional groups contribute to the sensitivity and antifouling properties of the electrode. We have uncovered the antifouling ability of different carbon nanomaterials on PPF oxidation products. Factors such as hydrophilicity, geometric morphology, and active surface area played pivotal roles in antifouling. Furthermore, surface modification with hydrophilic polydopamine further enhanced the antifouling effects. In this study, we extensively investigated the electrochemical oxidation of PPF and its oxidation product on carbon nanomaterials, as well as the antifouling mechanism of carbon nanomaterials. The modified electrodes exhibit excellent antifouling performance and stability. This achievement presents a promising approach towards the development of point-of-care PPF analysis in clinical settings. [ABSTRACT FROM AUTHOR]

[Display omitted] • Innovative CoMn-Fe/NF heterostructure electrode design for superior supercapacitors. • Optimal heterostructure design improves ion mobility, boosts active sites, and reduces charge transfer resistance. • The CoMn-Fe/NF electrode demonstrates a remarkable specific capacitance of 2633 Fg−1 at 1 A g−1. • The CoMn-Fe/NF electrode achieves an energy density of 87.80 Wh kg−1 at 0.245 kW kg−1. The pursuit of enhanced energy storage efficiency has driven the development of hybrid electrode structures. Overcoming the limitations of single-component metal oxides regarding stability and ionic electron mobility, we have engineered a hybrid structure, CoMn-Fe/NF. This structure comprises vertically grown Fe 2 O 3 nanosheets on CoMn layered doubled hydroxide (LDH) nanowires anchored on nickel foam (NF) via a hydrothermal synthesis method. This hybrid configuration demonstrated a remarkable specific capacitance of 2633F g−1 at 1 A/g, coupled with exceptional stability. When integrated into a supercapacitor device, it achieved a high energy density of 87.80 Wh kg−1 at a power density of 0.245 kW kg−1 while maintaining outstanding cycling performance. The interconnected network of nanowires and nanosheets in CoMn-Fe/NF facilitated ion mobility and provided abundant accessible active sites, resulting in robust electrochemical activity, low resistance, and enhanced supercapacitor performance. This study introduces an innovative strategy for synthesizing electrode materials with significant potential for high-performance hybrid supercapacitors, representing a substantial advancement in the development of efficient energy storage devices. [ABSTRACT FROM AUTHOR]

[Display omitted] • SnO 2 nanosheets assembled flower-like structures were prepared through hydrothermal method. • Oxygen vacancy content was modulated with argon-based plasma over different exposure durations. • Rich oxygen vacancies provided superior results for the sensor with 7 min plasma exposure. • The optimum sensor exhibits good sensitivity and prominent selectivity towards formaldehyde. Effective utilization of nanostructured metal-oxides with surface engineering is often overlooked during fabrication of gas sensors. The paper reports preparation of flower-like tin oxide nanosheets (average thickness = 12 nm) enriched with oxygen vacancies towards enhanced formaldehyde detection. The proportion of oxygen vacancy was increased using argon-plasma treatment (power = 100 W) with varied time durations (0, 2, 4, 7, 10 min). A detailed material characterization confirmed the structural property and oxygen vacancy content in the samples. A comparative sensing performance was analyzed among different fabricated sensor devices based on plasma exposure duration. Superior sensing behavior was registered from sensor S_7 comprising of sample with 7 min plasma exposure having maximum oxygen vacancy content of 53.16 % (relative). Sensor S_7 was considered optimum, which showed a response of 24.19 in presence of 10 ppm of formaldehyde which was 8.6 times greater than the sensor (S_0) without plasma exposure. Remarkably, sensor S_7 exhibited high sensitivity, fast kinetics, excellent reversibility, notable repeatability, and admirable selectivity, along with 34 ppb as limit of detection. Additionally, the sensing mechanism is adequately discussed based on the surface interaction, electronic sensitization and associated redox reactions. The demonstrated work emphasizes an efficacious approach toward developing upgraded gas sensor devices for widespread applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • 2D OV-Ce-MoO 3 /Pt nanosheet is created by a two-step method and used methanol oxidation. • Ce and oxygen vacancy introduction well regulated the structure and property of MoO 3. • It shows electrocatalytic activity of 1247 mA mg−1 and poisoning-tolerance ability. • Under light irradiation, its electrocatalytic activity is increased to 2858 mA mg−1. MoO 3 with Pt-like d-band center electronic structure is an ideal catalyst carrier, but its low conductivity, wide-bandgap and poor photoresponse limits the application of photoelectrocatalysis. Designing doping and oxygen vacancies simultaneously in MoO 3 is a candidate strategy to address some challenges. Herein, a 2D oxygen-vacancies Ce-MoO 3 /Pt (OVs-Ce-MoO 3 /Pt) nanosheet is developed using a two-step method of hydrothermal and chemical reduction. The band gap, optical properties, and methanol adsorption capacity of MoO 3 are well regulated after Ce doping and oxygen vacancy introduction. Profiting by the synergistic promotion of sufficient oxygen vacancies and Ce element, the OVs-Ce-MoO 3 /Pt catalyst exhibits super-efficient photoelectrocatalytic activity (2858 mA mg−1) and poisoning-tolerance ability towards methanol oxidation, which is superior to the Ovs-MoO 3 /Pt catalyst (1542 mA mg−1) and commercial JM Pt/C catalyst (377 mA mg−1). These results indicate that the OVs-Ce-MoO 3 /Pt catalyst can serve as a highly promising catalyst in the field of photoelectrocatalysis. [ABSTRACT FROM AUTHOR]

[Display omitted] • Sn 4 P 3 /P-doped C@CNs composites were prepared by simple and environmentally friendly synthesis method. • The composites were composed of ultra-small Sn 4 P 3 and 3D P-doped porous carbon nanosheets. • The Sn 4 P 3 /P-doped C@CNs exhibited excellent electrochemical performance. • The role of P-doped CNs and ultra-small Sn 4 P 3 were investigated. Transition-metal phosphides (TMPs) with high theoretical specific capacity and appropriate reaction potential have been recognized as prospective anode materials for lithium-ion batteries (LIBs). However, the practical application is still hindered by the inferior rate capability and worse cycling stability, which is mainly arising from large volume variations and inferior electric conductivities of TMPs. Herein, ultra-small Sn 4 P 3 particles are fully embedded into three-dimensionally interconnected P-doped porous carbon nanosheets (Sn 4 P 3 /P-C@CNs), which is fabricated by a feasible and environmentally friendly synthesis strategy with phytic acid as phosphorus source. The ultra-small Sn 4 P 3 particles and the conductive P-doped 3D carbon backbone is advantage to alleviate the volume changes of Sn 4 P 3 nanoparticles, reduce side reaction with electrolyte and promote the transfer of ions/electrons, leading to a significant improvement in electrochemical performance. Consequently, the Sn 4 P 3 /P-C@CNs composite electrode delivers a high reversible capacity of 770 mA h g−1 at 0.1 A/g upon 100 cycles, and exhibits 717 mA h g−1 at 1 A/g after 1000 loops. The lithium storage mechanism is investigated by density functional theory calculations. This research could offer a sensible and facile design strategy for TMPs-based electrode materials and make it hopeful for the applications in next-generation high-energy–density LIBs. [ABSTRACT FROM AUTHOR]

[Display omitted] • The peptides decorated g-C 3 N 4 hybrids were synthesized for enhanced photocatalytic activities. • The R-CN composite demonstrated excellent photocatalytic hydrogen under the visible light. • The strained heptazine planes in the g-C 3 N 4 structure is formed by the peptide deposition. • The electron redistribution and delocalization in the R-CN composite lead the band gap reduction. This work demonstrated the synthesis of peptides decorated porous g-C 3 N 4 hybrids (R-CN) for the enhanced photocatalytic H 2 production, where the 14-mer peptides were effectively deposited on g-C 3 N 4 nanosheets by electrostatic interaction. The prepared R-CN hybrid composite shows the enhanced visible light absorption due to the modulation of electronic structures of g-C 3 N 4 by the interaction between peptides and g-C 3 N 4. Therefore, the R-CN hybrid composite demonstrated the excellent photocatalytic H 2 production with yield of 2018 μmol·g−1·h−1 under the visible light irradiation, which is 14-time higher than that of pristine g-C 3 N 4. The theoretical study shows that the strained heptazine planes in the g-C 3 N 4 structure is formed in the R-CN hybrid composites by the electrostatic interaction between the positively charged amine group of peptides and the negatively charged edge N atom of g-C 3 N 4. Thus, the electron redistribution and delocalization in the R-CN composite lead the band gap reduction, build-in electrical field and electronic modulation. Therefore, the R-CN composites shows the enhanced charge separation and the optimized free energy of reaction intermediates for the excellent photocatalytic activities. These results are confirmed from the experimental measurements and the MD and DFT computations study. This work provides an effective strategy to design biomaterial-based metal-free photocatalysts for H 2 production. [ABSTRACT FROM AUTHOR]

[Display omitted] • The surface modification process of bulk g-C 3 N 4 induced spontaneous adsorption. • The surface energy during sintering can be controlled by the adsorbed nanosheets. • Sinterability is enhanced by the increased activation energy of surface diffusion. Yttria-stabilized zirconia (YSZ) is a ceramic material in which the zirconium dioxide structure is stabilized at room temperature by adding yttrium oxide. However, the YSZ formed by the thick film process on a pre-sintered dense substrate suffers from sintering problems such as different sintering shrinkage rates due to phase transitions and thermal conductivity. This in turn can lead to de-bonding, cracking, delamination, and abnormal growth. We prepared a spherical YSZ green body of approximately 38 μm diameter formed by an organic binder based on a sintered YSZ seed with 15 to 20 μm diameter. In addition, the application of two-dimensional g-C 3 N 4 nanosheets that can be adsorbed on the surface and pores of the green body before the sintering process was evaluated. The YSZ green body with adsorbed surface-modified g-C 3 N 4 nanosheets could be synthesized by stable spontaneous adsorption due to zeta-potential attraction onto the surface of zirconia particles in an aqueous solution. Consequentially, the formation of large grains due to abnormal grain growth was reduced as g-C 3 N 4 was adsorbed. The spontaneous adsorption of nanosheets controls the surface diffusion mechanism by sequentially lowering the energy from a high surface energy in the initial stage of sintering. Uniform grain growth thus can be induced according to the activation energy level of the controlled surface diffusion. [ABSTRACT FROM AUTHOR]

The type-II p-n heterojunction mechanism is a promising approach to significantly improve photocatalytic activity. In this work, we prepared type II layered p-n heterostructures by loading MoS 2 nanosheets on rod-like CAU-17 by a typical solvothermal process using Bi-MOF(CAU-17) as a precursor. Electron-hole complexation efficiency of nanocomposites analyzed by photoluminescence spectroscopy and electron microscopy. The results showed that the charge transfer channels provided by the heterogeneous structure between the nanocomposites significantly improved the charge transfer and separation efficiency, extended the lifetime of the reactive electrons, and facilitated the generation of reactive oxygen species, The nanocomposite type-II p-n heterojunction structure reduces the difficulty of photoelectron escape during photocatalysis and improves the photocatalytic efficiency. [Display omitted] • The prepared CAU-17/MoS 2 showed good photocatalytic antimicrobial activity. • The prepared CAU-17/MoS 2 was bonded in a type II p-n heterojunction, which formed a built-in electric field promoting electron-hole transfer. • CAU-17/MoS 2 has many types of pore sizes and abundant active sites. • CAU-17/MoS 2 have potential for tumor suppression. A novel visible-light-driven type II p-n heterojunction CAU-17/MoS 2 photocatalytic antifouling biocide was prepared and indicated significant inhibition against the most pharmaceutically recognized harmful microorganisms: gram-positive Staphylococcus aureus (S. aureus), gram-negative Escherichia coli (E. coli) and the drug-resistant bacterium methicillin-resistant Staphylococcus aureus (MRSA). The antimicrobial mechanism is attributed to the production of reactive oxygen species (ROS) such as •OH, 1O 2 due to the photocatalytic properties of CAU-17/MoS 2 heterojunction. The electron-hole complexation efficiency of the nanocomposites was analyzed using photoluminescence spectroscopy and characterized using electron microscope. It was found that the heterojunction structure of the nanocomposites provided multiple charge transfer channels to significantly improve the transporting and separating efficiency for the photo-induced electron-hole pairs, which consequently facilitated the production of ROS. Given the promising antimicrobial effects, further investigation on the broader application of CAU-17/MoS 2 biocides is needed to test the cytotoxicity, as well as the post-bacteriostatic wound healing effect upon animal models. [ABSTRACT FROM AUTHOR]

Ultrafine Ni x -NiO nanoparticles supported on cogenerated mesoporous SiO 2 skeleton was utilized as an air-stable and reusable catalyst for the selective semi-hydrogenation of alkyne to corresponding Z -alkene. [Display omitted] • Porous silica-supported ultrafine NiO was prepared by one-pot strategy. • NiO nanoparticle is highly dispersed and confined in the cogenerated SiO 2 skeleton. • The surface of NiO nanoparticle can be partially reduced to Ni x -NiO by NaBH 4. • Metallic Ni on Ni x -NiO was active due to the moderate adsorption/desorption energies. • It shows constant good activity and selectivity after a long-term storage in air. The practical application of non-noble metal-based hydrogenation catalysts is limited because of their low activity and easy oxidation in air. Here, porous silica-supported ultrafine nickel oxide (NiO) was prepared by calcining an organic–inorganic hybrid 3D nanomaterial that was formed via the Michael addition/Schiff's base reaction, and hydrolyzation of triethoxysilane. NiO nanoparticles with ca. 2.6 nm diameter was uniformly dispersed and confined in the cogenerated mesoporous SiO 2 skeleton, thanks to the coordination between pyrogallol/amino units and Ni2+ ions, and the isolation effect of Si-O-Si network. The as-prepared catalyst featured mesoporous structure and high specific surface area (715 m2/g), and exhibited excellent activity, selectivity and reusability in the semi-hydrogenation of alkynes. Small amount of metallic nickel (Ni x -NiO) that formed on the surface of NiO nanoparticles during the semi-hydrogenation acted as the active species, and the moderate adsorption/desorption energies on Ni x -NiO facilitated the activity enhancement. Most importantly, it showed constant catalytic activity and selectivity after a long-term storage in air. This work provides a green and feasible strategy, as an alternative to the traditional impregnation method, for the preparation of ultrafine metal-supported catalysts with air-stability and reusability. [ABSTRACT FROM AUTHOR]

[Display omitted] • The composite was synthesized by a hydrothermal and vapor phase sulfidation method. • The hetrostruction and MXene improve the Na+ reaction kinetics. • The composite exhibits excellent rate and superior cycle stability. Molybdenum trioxide (MoO 3) is regarded as a promising material for rechargeable batteries attributed to its low cost, high theoretical capacity and eco-friendliness. Herein, N-doped carbon (NC) coated MoO 3 /MoS 2 composite decorated on MXene nanosheets (MoO 3 /MoS 2 /NC/MXene) has been synthesized by gas-phase vulcanization and coating of NC. The electrical conductivity and kinetics of ion diffusion/transport are greatly enhanced due to the vulcanization, NC coating and introduction of MXene. As a consequence, the composite exhibits high discharge capacity of 464 mAh/g at a current density of 0.1 A/g and still maintains a capacity of 202 mAh/g at a high current density of 5 A/g when used as the anode material for sodium-ion batteries. Furthermore, the electrode material still remains a high discharge capacity of 320 mAh/g with the capacity retention rate of nearly 100 % after 2000 cycles at a current density of 1 A/g. [ABSTRACT FROM AUTHOR]

Approximately 7 at% of Yb-doped monolayer WS 2 nanosheets are successfully prepared by in-situ chemical vapor deposition technique. The performances of the photodetectors based on WS 2 (Yb) are significantly enhanced after RE doping, providing an excellent strategy for preparing high-performance 2D material optoelectronic devices. [Display omitted] • Approximately 7 at% of Yb substitutionally doped monolayer WS 2 nanosheets are prepared by in-situ chemical vapor deposition (CVD) technique. • DFT calculations demonstrate a shrinked bandgap of Yb-doped monolayer WS 2 at K point, indicating much higher of electronic states and thus higher probability of the transitions for better electronic performances. • The mobilities, photocurrents, photoresponsivity, and external quantum efficiency of the photodetector based on WS 2 (Yb) are better than those of the pristine WS 2 , proving a high effectiveness of RE doping in 2D materials and providing a guide for the preparation of 2D materials with excellent optical and optoelectronic performances. The study of rare-earth (RE) doping in two-dimensional (2D) transition metal dichalcogenides (TMDCs) has become an important research focus to modulate bandgaps and carriers for production of the exotic properties. Herein, approximately 7 at% of Yb substitutionally doped monolayer WS 2 nanosheets are prepared by in-situ chemical vapor deposition (CVD) technique. Highly enhanced optical and electrical properties are obtained: Three times enhancement in photoluminescent intensities and 5.6 nm of red-shifts in wavelength are observed from their peaks after chemical doping. First-principles calculations based on density functional theory (DFT) demonstrate a shrinked bandgap of Yb-doped monolayer WS 2 at K-point in Brillouin zone compared with that of the pristine WS 2 monolayer, and a broadened absorption and reflectivity spectra from visible to near-infrared region, which is in good agreement with the experimental results. Photodetectors based on Yb-doped monolayer WS 2 nanosheets show far higher of mobility (17 times), photocurrent, photoresponsivity, and external quantum efficiency than those of the pristine WS 2. The results prove a high effectiveness of RE doping in 2D materials for high-performance optoelectronic devices. [ABSTRACT FROM AUTHOR]

Pt nanoparticles decorated NiFeP nanosheets arrays on nickel foam (Pt-NiFeP/NF) with branch-like hierarchical nanostructures were successfully synthesized. Benefiting from the compositional and structural advantages, Pt-NiFeP/NF catalyst exhibited outstanding bifunctional UEOR and HER performance with long-term operating stability in alkaline electrolyte. [Display omitted] • Pt nanoparticles decorated NiFeP nanosheets arrays on nickel foam (Pt-NiFeP/NF) were successfully synthesized. • The introduction of Pt nanoparticles can accelerate the reaction kinetics of HER and UEOR. • The hydrophilic surface and porous ultrathin nanosheets arrays exposure abundant active sites and facilitate electron/mass transfer. • Pt-NiFeP/NF exhibits superior activity for both UEOR and HER with robust stability. Urea-assisted water electrolysis is a clean, sustainable, and energy-saving method towards hydrogen production. However, the development of earth-abundant, stable, and highly active bifunctional catalysts towards urea electrolysis is still a significant technical challenge. Herein, the highly dispersed Pt nanoparticles decorated NiFeP nanosheets arrays on nickel foam (Pt-NiFeP/NF) electrode is rationally designed, which combines the advantages of superhydrophilic interface, ultrathin nanostructure and open three-dimensional (3D) architecture. Consequently, Pt-NiFeP/NF displays a remarkable electroactivity towards both hydrogen evolution reaction (HER) and urea electrooxidation reaction (UEOR), which only needs the overpotential of 32 mV to achieve the current density of 10 mA cm−2 towards HER, and drives a current density of 50 mA cm−2 at 1.38 V towards UEOR. More importantly, the urea electrolysis system assembled with Pt-NiFeP/NF only requires a cell voltage of 1.41 V to achieve a current density of 100 mA cm−2, much lower than the traditional water electrolysis (1.94 V). This work promotes the application of Pt nanoparticles decorated bimetallic phosphides as a bifunctional catalyst towards urea-rich wastewater treatment and green electrochemical hydrogen production. [ABSTRACT FROM AUTHOR]

[Display omitted] • BODIPY modified Mo 2 C nanosheets were prepared via electrostatic interaction. • Mo 2 C nanosheets showed high photothermal conversion efficiency. • BODIPY-Mo 2 C nanosheets demonstrated strong photocatalytic activity. • BODIPY-Mo 2 C nanosheets exhibited highly efficient antibacterial via photothermal/photodynamic effects. The advancement of novel MXene materials characterized by heightened stability and remarkable antibacterial attributes has garnered substantial attention in recent research endeavours. In this article, it is first time to prepare boron dipyrromethene (BODIPY) modified Mo 2 C nanosheets (BODIPY-Mo 2 C) via electrostatic interactions to achieve the desirable antibacterial property, enriching by both photothermal and photodynamic effects. The photothermal conversion efficiency of the produced Mo 2 C nanosheets reached to 42.6 %. Furthermore, in the photothermal antibacterial tests against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), both Mo 2 C and BODIPY-Mo 2 C demonstrated 100 % antibacterial efficiency at a concentration of 100 μg·mL−1. Remarkably, at a lower concentration gradient of 75 μg·mL−1, BODIPY-Mo 2 C nanosheets showed clearly enhanced antibacterial capabilities compared to pure Mo 2 C, underscoring the efficacy of BODIPY in boosting the antibacterial performance of Mo 2 C. [ABSTRACT FROM AUTHOR]

Figuratively speaking, (C 6 H 5) 4 P+ and(C 6 H 5) 4 B- are assembled together like picture puzzles, achieving tight binding of P and B sources at the molecular level. After pyrolysis, the P/B co-doped carbon nanosheets obtained by bottom-up strategy exhibits superb ORR electrocatalytic performances due to the controllable nanosheet structure and abundant heteroatomic active sites. [Display omitted] • A bottom-up puzzle strategy is proposed to fabricate P/B co-doped nanocarbon. • Diverse nanosheets are achieved by using different P onium salts. • Self-assembly mechanism of P/B sources and further evolution are elucidated. • 4P-BC with ample P/B-induced active sites exhibits superb ORR activities. • This strategy provides a novel avenue for the design of metal-free electrocatalysts. Preparing metal-free and non-N-doped carbon-based electrocatalysts via pyrolysis encounters a significant challenge of low controllability for microstructure modulation and limited electrocatalytic activity. Herein, a bottom-up puzzle strategy is proposed to fabricate a series of phosphorus and boron co-doped carbon (P-BC) nanosheets. These P-BC nanosheets manifest diverse morphologies and distinct heteroatom doping levels, achieved through the innovative utilization of four similar P onium salts featuring varying benzene ring arrangements, coupled with a fixed B onium salt. Among them, the flat 4P-BC nanosheets with abundant P/B heteroatoms exhibit the optimal oxygen reduction reaction (ORR) performance (E 1/2 = 0.79 V, j L = 5.77 mA cm−2), and the assembled zinc-air battery displays a large power density (163 mW cm−2) and excellent long-term durability (450 cycles), which is attributed to the high specific surface area, enhanced defects or disorder, and ample P/B-doping induced active sites for electrochemical reaction. The assembly mechanism of functional units in solution and their intricate evolution at high temperature are elucidated for various P-BC nanosheets. This work elaborates the influence of precursors functional units on the resulting microstructure attributes and active sites properties, providing a novel avenue for the rational design and optimization of metal-free and heteroatom-doped carbon electrocatalysts. [ABSTRACT FROM AUTHOR]

[Display omitted] • The tetrahydrofuran molecule was connected to g-C 3 N 4 (TCN). • TCN had better photocatalytic removal rate to organic dyes, Cr6+, and tetracycline. • The photoelectron-hole complexation time of TCN is longer than CN. • TCN had stable photocatalytic performance after heat or strong acid treating. Photocatalysis offers a green and promising strategy for light-driven pollutant degradation to address water pollution. Yet, challenges in conversion efficiency and cost-efficiency propel the search for effective metal-free photocatalysts. Here, we employ a ball milling technique using organic solvent molecules to enhance the exfoliation of g-C 3 N 4 nanosheets. Incorporating tetrahydrofuran, with its distinctive five-membered monooxygenase ring structure, endows exfoliated CN nanosheets (TCN) with remarkable electron-donating capabilities, expanding specific surface area and active sites, essential for intricate photocatalytic reactions. Comparative assessments unequivocally establish TCN's superiority, revealing a remarkable 3.6-fold enhancement in RhB dye degradation and a remarkable 99.7 % removal efficiency. TCN demonstrates rapid, complete reduction of heavy metal ions (Cr6+) under natural sunlight within 10 min and exhibits a significant 2.3-fold antibiotic degradation enhancement over pristine CN. This pioneering work unveils the mechanisms behind TCN's superior photocatalytic performance, offering insights into designing advanced photocatalysts for crucial water purification applications. [ABSTRACT FROM AUTHOR]

Developed bifunctional, efficient, durable, green, economical, and sustainable NiCo 2 O 4 @FSSM electrode with enhanced electrocatalytic activity for water splitting. [Display omitted] • Economic and binder-free synthesis of bifunctional NiCo 2 O 4 @FSSM for water splitting. • Low overpotential of 310 mV (OER) and 79 mV (HER)@ 10 mA cm−2. • OER and HER stability of NiCo 2 O 4 @FSSM examined for 43 h. • Practical applicability of NiCo 2 O 4 @FSSM explored in the large-scale set-up. • Scale-up showed O 2 (7.4 L) and H 2 (11.5 L) evolution in 25 h. Water as a green source of hydrogen has attracted the attention of researchers considering its potential applications in the energy sector. Thus, developing efficient bifunctional electrocatalysts for water splitting is a potential challenge perceived by researchers exploring the development of sustainable energy technologies. With this motive, the present study focuses on the preparation of the highly active, economic, binder-free, and bifunctional NiCo 2 O 4 nanosheets@ Flexible Stainless Steel Mesh substrate (NCO@FSSM) electrocatalyst via reflux condensation method for the bulk O 2 and H 2 production. The influence of reflux condensation temperatures (100, 120, 140 °C) on the morphology and electrocatalytic activity is investigated. Electrocatalytic properties for NCO@FSSM synthesized at 120 °C were noted exhibiting smaller overpotentials for oxygen evolution reaction (OER, 310 mV) and hydrogen evolution reaction (HER, 79 mV) at 10 mA cm−2, which were lowest among the previously reported Ni, and Co-based electrodes. Additionally, the scale-up experiments with NCO-120@FSSM film (8 cm X 8 cm) as an anode and FSSM as a cathode and vice-versa, in a specially designed scale-up electrochemical cell revealed steady electrocatalytic performance. The real-time water splitting was studied for 25 h and was noted to produce 7.4 L of (O 2) and 11.5 L of hydrogen (H 2). [ABSTRACT FROM AUTHOR]

The composite material with 155 mA h/g at 10 C and 97.6% retention after 1000 cycles, achieving C/N/S co-doping in mesoporous Li 4 Ti 5 O 12 nanosheets, which increases the lattice size and enhances the concentration of oxygen vacancies. The narrowed band gap contributes to the increase in conductivity. In this case, S6+ ions were doped into the Ti sites, less S2− and N3– ions were doped into the O sites or as a whole in the form of N-doped C doped into LTO. The CTAB as a structure-guiding agent and the dopant ions of different valence states are derived from CTAB and TAA. [Display omitted] • The material achieves the C/N/S co-doping at the Ti and O positions in situ. • C/N/S co-doping increases the lattice size of LTO and forms abundant oxygen vacancies. • The 2D mesoporous nanosheet provides a high surface area and a short diffusion path of Li+. • C/N/S co-doped LTO nanosheet obtains high-rate capacity and long-term life. The low capacity of Li 4 Ti 5 O 12 (LTO) under high-rate charging/discharging limits its development in energy applications. Two-dimensional (2D) nanosheets equipped with mesopores offer promising opportunities to realize high-rate and long-term lithium-ion batteries. This paper successfully synthesized C/N/S co-doped lithium titanate nanosheets with rich oxygen vacancy concentration (CNSLTO) in a single step. C, N and S are doped into the LTO bulk phase, providing bulk oxygen vacancies and active sites. Partial Ti4+ conversion to Ti3+ is promoted by co-doping and introducing rich oxygen vacancies, improving the electrical conductivity. In addition, the effect of CTAB concentration on the morphology and electrochemical properties of the materials was studied experimentally. The optimized CNSLTO nanosheets have a relatively high specific surface area (99.38 m2 g−1) and numerous mesoporous, achieving outstanding performance and excellent cycling stability at high-rate as lithium-ion anode materials. The CNSLTO exhibits excellent rate capacity (171.7–152.6 mA h g−1 at 0.5–20 C) and cycling performance (97.6 % after 1000 cycles at 10 C). Additionally, the discharge-specific capacity of the LFP//CNSLTO full battery at 10 C (122.2 mA h g−1) was superior to the LFP//LTO (77.8 mA h g−1). [ABSTRACT FROM AUTHOR]

[Display omitted] • Mn-FeOOH/g-C 3 N x composites were prepared by a two-step method. • N/O double vacancy were successfully constructed in the composite. • The carbon network is a prerequisite for the stable existence of the double vacancy. • The N/O double vacancy directly activates the O−O bond in the PMS. • N−(C) 2 adsorption of As improves mass transfer rate and accelerates the catalytic process. Nitrogen deficient porous nanosheets(NDCN) are a promising nano template that can combine defect engineering with Mn-FeOOH to suppress photo generated carrier complexation and optimize electron distribution. In this study, a unique structure with N/O double vacancies in Mn-FeOOH@NDCN was prepared using a magnesium thermal denitrification co-precipitation method. Furthermore, a series of Mn-FeOOH/NDCN/PMS reaction systems were constructed by adjusting the dosage of peroxymonosulfate(PMS). The experimental results indicate that the synergistic activation of N/O double vacancies on PMS enables the Mn-FeOOH/NDCN/PMS system to oxidize almost 10 mg/L of As(III) within 90 min. At the same time, the oxidized As(V) was completely adsorbed, thereby completely removing the total arsenic in the water. The reasonable construction of carbon networks is a prerequisite for the stability of Mn-FeOOH/NDCN composite catalysts, enabling them to have good cyclic stability. The experimental results confirm that oxygen vacancies directly participate in the activation of PMS, while nitrogen vacancies effectively adsorb As(III), thereby promoting the contact between As(III) and PMS, improving the mass transfer rate, and accelerating the catalytic degradation process. This study will provide a new way to completely remove arsenic pollution from water bodies. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hollow, yolk-shell and porous structure was integrated on one material by simple method. • Nickel/carbon composite with double-shell hollow porous structure exhibited extraordinary microwave absorption performance. • Strong reflection loss at C band, X band, and Ku band was realized by regulating the structure of Ni/C composite. Designing structure at the nanoscale of materials has been proved to be an effective way to control electromagnetic parameters and optimize microwave absorption performance. For constructing lightweight microwave absorption materials, abundant studies focus on the preparation of absorbent with hollow, porous or yolk-shell structure. However, it is still a challenge to integrate multiple structures on one material by simple method. In this work, we found that the addition of citric acid in the preparation process played an extremely important role in regulating the structure of Ni-MOF, and developed one-step approach to synthesis double-shell hollow porous Ni-MOF. After the carbonization process, the Ni/C composite was obtained. The controllable morphology of Ni-MOF endowed Ni/C composite adjustable absorbing properties. Under the assistance of citric acid, the Ni/C composite with yolk-shell, porous, as well as double-shell hollow porous structure was also synthesized. The optimal reflection loss was −56.18 dB, the broadest bandwidth was 6.1 GHz at 2.2 mm for double-shell hollow porous Ni/C composite. Particularly, strong reflection loss at C band, X band, and Ku band was realized by regulating the structure of Ni/C composite. This work revealed the mechanism of microstructures regulating the absorbing properties, which could be beneficial to the further development of MOFs derived absorbent. [ABSTRACT FROM AUTHOR]

[Display omitted] • CsPb 2 Cl 5 nanosheets were successfully synthesized by employing a straightforward solution method. • The determination of CsPb 2 Cl 5 as an indirect bandgap semiconductor has been ascertained through band structure theory calculations. • By modulating substrate temperature and substrate material, the controlled growth of CsPb 2 Cl 5 nanosheets has been achieved. • For the first time, CsPb 2 Cl 5 nanosheets have been employed in ultraviolet photodetectors, yielding a dark current at the picoampere level and exceptional stability. CsPb 2 Cl 5 nanosheets were grown on different substrates by a simple solution method using dilute hydrochloric acid and absolute ethanol as solvents. The effect of temperature on the nanosheet growth was investigated. It was turned out that lower temperature is beneficial to the formation of nucleation of nanosheets. The nanosheet size changed from 20 μm to 60 μm, and the thickness gradually decreased from 750 nm to 120 nm as the growth temperature increased. The nucleation rate and distribution caused by contact angle induced solute transport on different substrates were obtained. The CsPb 2 Cl 5 nanosheets were confirmed to possess a large Stokes shift and broad emission spectrum in the PL and prolonged carrier lifetime in transient fluorescence lifetime measurements. An ultraviolet photodetector based on CsPb 2 Cl 5 nanosheets was reported for the first time. An extremely low dark current (pA-level), large on–off ratio and a fast response time with a rise time of 17 ms and a decay time of 32 ms were obtained. The detector placed in air without any package for over 2100 h still maintains 85 % photocurrent of the initial value. [ABSTRACT FROM AUTHOR]

[Display omitted] • NiS 2 /MXene nanocomposites are synthesized by in situ self-assemblied method. • NiS 2 /MXene nanocomposites are used to functionalize the separator. • A multifunctional separator, as trapper-catalyst-conductor, is used in Li-S battery. • The separator efficiently trap, catalyze conversion for LiPSs, and transport e−/Li±. • NiS 2 /MXene-based Li-S batteries show high performances and long cycling stability. The notorious shuttling effect and sluggish redox kinetics towards lithium polysulfides (LiPSs) seriously hinder the practical application of lithium-sulfur (Li-S) batteries. The development of a multifunctional separator, as cooperator of trapper-catalyst-conductor, is deemed to be an efficient and feasible solving strategy. Herein, the NiS 2 /MXene nanocomposites with mesoporous structures were synthesized by the hydrothermal reaction, in which 0D ultrafine NiS 2 nanoparticles were in situ self-assembled on 2D conductive MXene nanosheets. The NiS 2 /MXene nanocomposites were then modified on PP separators to form a thin layer of 8 μm in the Li-S batteries, which exhibit the significant characteristics of capture and conversion of LiPSs, as well as highly-efficient transferring pathways of electron/Li+ via the synergetic effect of NiS 2 and MXene from their strong chemisorption abilities, rich catalyzing active sites, and high electron conductivity, accelerating to the redox reaction kinetics of LiPSs. Consequently, these Li-S batteries by using the modified PP separators show a high reversible capacity of 805.1 mAh/g at 0.2 C after 200 cycles. Even at 2 C, it still exhibits a low capacity decay of 0.038 % per cycle after long-term stable 1000 cycles. This work proves that the developing multifunctional separators are efficient strategies for high performance Li-S batteries. [ABSTRACT FROM AUTHOR]

An ultrathin CoO@NC nanosheet is prepared with NaBH4-treated ZIF-67 and can degrade ofloxacin rapidly and effectively as an AOP catalyst. [Display omitted] • After treated by NaBH4, ZIF-67 is partially delaminated and curled. • The derived CoO@NC exhibits an ultrathin carbon nanosheet loaded with highly dispersed CoO NPs. • The CoO@NC can decompose ofloxacin via both radical and non-radical pathways. • A high ofloxacin removal efficiency (96.8 %) is achieved by P-CoO@NC after reacting for 10 min. • Four ofloxacin degradation pathways are proposed. Modulating the morphology of precursor can effectively adjust the property of derived composite. Herein, after post-treated by NaBH 4 , a layered ZIF-67 precursor was endowed with high porosities, partially delaminated and curled layers. With this material as precursor, the pyrolysis composite, P-CoO@NC, exhibits a morphology of ultrathin N-doped carbon (NC) nanosheets coupled with highly dispersed CoO nanoparticles. This composite can active peroxymonosulfate (PMS) and degrade ofloxacin (OFL) with an efficiency of 96.8 % (10 min). After recycling for five times, the degradation efficiency can still reach 82.5 %, which demonstrates its catalytic activity and stability as an advance oxidation process (AOP) catalyst. As confirmed by related experiments, both radical (SO 4 — and O 2 —) and non-radical (1O 2) pathways take part in OFL degradation in P-CoO@NC system. Overall, this work demonstrates a specific role of NaBH 4 in modulating MOF precursor and further the property of derived composite. [ABSTRACT FROM AUTHOR]

[Display omitted] • Nano-sized BiPO 4 /rGO was prepared. • The embedding of rGO effectively limits the volume expansion of the BiPO 4. • BiPO 4 /rGO nanomaterials showed excellent performance. BiPO 4 /reduced graphene oxide (BiPO 4 /rGO) composites were prepared by solvothermal method and annealing process. In terms of cycle and rate performance, BiPO 4 /rGO composites surpasses BiPO 4 when utilized as anode materials in potassium ion batteries (PIBs). The discharge capacity of BiPO 4 /rGO composite maintained 204 mAh/g after 500 cycles at 100 mA g−1. The capacity might reach 194 mAh/g at a high current density of 1000 mA g−1. Additionally, the electrochemical reaction mechanism of BiPO 4 /rGO composites in potassium ion batteries is studied using an ex-situ XRD test. [ABSTRACT FROM AUTHOR]