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A novel electrochemical activation method was used to convert Bi(OH) 3 into α-Bi 2 O 3 with abundant oxygen vacancies. This material has a high specific capacitance and more persistent cycling stability than δ-Bi 2 O 3.When assembled into a hybrid supercapacitor, it shows an energy density of up to 114.9 Wh kg−1. [Display omitted] Bi 2 O 3 is an outstanding electrode material due to its high theoretical specific capacity. Hence, the synthesis of δ-Bi 2 O 3 materials with high oxygen-vacancy contents could improve their electrochemical performances but causes easy conversion to α-Bi 2 O 3 with low oxygen-vacancy contents, leading to poor cycling stability and limited practical applications. To overcome these problems, an effective strategy for constructing high oxygen vacancies α-Bi 2 O 3 on activated carbon fiber paper (ACFP) is developed in this study. To this end, ACFP/Bi(OH) 3 is first synthesized by the solvothermal method and then converted to ACFP/α-Bi 2 O 3 by in situ electrochemical activation. The proposed innovative electrochemical method quickly and easily introduces oxygen vacancies while preserving the three-dimensional structure, thereby promoting the charge transfer and ions diffusion in ACFP/α-Bi 2 O 3. Consequently, the specific capacity of ACFP/α-Bi 2 O 3 reaches 906C g−1 at 1 A g−1, and the capacity retention remains above 70% after 3000 cycles, a value higher than that of δ-Bi 2 O 3 (45%). Furthermore, the hybrid supercapacitor device assembled by ACFP/α-Bi 2 O 3 delivers a maximum energy density of 114.9 Wh kg−1 at 900 W kg−1 and outstanding cycle stability with 73.56 % retention after 5500 cycles. In sum, the proposed ACFP/α-Bi 2 O 3 with high performance and good stability looks promising for use as bismuth-based anode materials in supercapacitors and aqueous batteries. [ABSTRACT FROM AUTHOR]

[Display omitted] • 1D MWO 4 (M = Mn, Co, Cd) nanomaterials were synthesized by electrospinning method. • CoWO 4 nanotubes exhibited superior efficiency in degrading BPA under UV–Vis–NIR light. • The wide-spectrum responses mechanism for MWO 4 (M = Mn, Co, Cd) were explained by DFT. Broadening the absorption region to near-infrared (NIR) light is critical for the photocatalysis due to the larger proportion and stronger penetration of NIR light in solar energy. In the present paper, one-dimensional (1D) MWO 4 (M = Mn, Co, and Cd) materials synthesized by electrospinning technique, were studied by combining the density functional theory (DFT) with experiment results, which possessed the enhanced light absorption capability within the range of 200–2000 nm. It was proved that in the ultraviolet–visible (UV–Vis) region, the absorption bands of CoWO 4 and MnWO 4 samples were attributed to the metal-to-metal charge transfer mechanism, while the absorption of CdWO 4 sample may be referable to the ligand-to-metal charge transfer mechanism. In the near-infrared (NIR) region, the absorption of CoWO 4 and MnWO 4 primarily originated from the d-d orbital transitions of Mn2+ and Co2+. The photocatalytic experimental results showed that the degradation rates for bisphenol A (BPA) over CoWO 4 , MnWO 4 , and CdWO 4 photocatalysts under UV–Vis/NIR light irradiation for 140 min/12 h were 78.8 %/75.9 %, 23.8 %/21.3 %, 12.8 %/8.7 %, respectively. This research offers the novel insights into the precise construction of tungstate catalytic systems and contributes to the advancement of UV–Vis–NIR full spectrum photocatalytic technology, and lays a foundation for a cleaner and more environmental-friendly future. [ABSTRACT FROM AUTHOR]

[Display omitted] • Bi 2 O 2 S 2D nanosheets films were prepared in-situ by one-step hydrothermal method. • [hk1] oriented Sb 2 S 3 NRs were epitaxially grown on Bi 2 S 3 transformed from Bi 2 O 2 S. • 2D/1D Bi 2 O 2 S/Sb 2 S 3 heterojunction constructed a rapid electron migration channel. • The TiO 2 /Bi 2 O 2 S/Sb 2 S 3 -annealed photoelectrode showed 4.37 mA/cm2 at 1.23 V RHE. Bismuth oxysulfide (Bi 2 O 2 S) is a layered material with high carrier mobility, excellent light absorption characteristic and good stability. However, there are few reports about the use of Bi 2 O 2 S in photoelectrochemical (PEC) water splitting. In this paper, Bi 2 O 2 S nanosheets (NSs) films were prepared on FTO substrates by one-step hydrothermal method, which broke the traditional powder state of Bi 2 O 2 S prepared. Based on the high lattice matching between antimony sulfide (Sb 2 S 3) and bismuth sulfide (Bi 2 S 3) obtained from the topological transformation of partial Bi 2 O 2 S, Sb 2 S 3 nanorods (NRs) with [hk1] predominant orientation were epitaxially grown on the surface of Bi 2 O 2 S to establish a transport channel for rapid carrier migration. Titanium dioxide (TiO 2) electron transport layer with oxygen vacancies was introduced into the back to capture and release electrons, further reducing the recombination rate. The photocurrent density of TiO 2 /Bi 2 O 2 S/Sb 2 S 3 -annealed photoelectrode at 1.23 V vs. RHE was 4.37 mA/cm2, which was 13.7 times that of monomer Bi 2 O 2 S. In addition, the TiO 2 /Bi 2 O 2 S/Sb 2 S 3 -annealed photoelectrode had lower charge transfer resistance and the IPCE value up to 48.22%. This study is of great significance for the application of Bi 2 O 2 S based photoelectrodes in the field of PEC water splitting. [ABSTRACT FROM AUTHOR]

[Display omitted] • A strongly coupled CoP-C/CN photocatalyst is prepared by using amorphous carbon layer as intermediate medium. • A new charge transfer pathway was constructed through VDW forces and P-C bonds. • CoP-C/CN exhibits much enhanced charge transfer and separation efficiency. • CoP-C/CN shows superior activity and stability for photocatalytic H 2 evolution by visible light. Enhancing the charge transmission rate at the interface of transition metal phosphide cocatalysts is an efficient technique to reinforce the photocatalytic activity action of semiconductors, but achieving a faster interface charge transfer rate remains a challenge. This paper reported the coupling of a two-dimensional carbon layer supported CoP (CoP C) as a non-noble metal heterostructure catalyst and a two-dimensional porous graphite carbon nitride (CN) photocatalyst to enhance the transmission rate of photogenerated carriers at the interface. Detailed characterizations and mechanism research have confirmed that the P C bond and Van der Waals heterojunction at the interface function as a novel charge transmission channel, which facilitates the effective transfer of photogenerated carriers from CN to CoP. Furthermore, the large contact area exhibited by the 2D/2D Van der Waals heterojunction offers an increased number of active sites for hydrogen evolution reactions. Consequently, the composite material (CoP C/CN) formed by the coupling of CoP C and CN has an enhanced H 2 production rate of 1503 μmol∙g−1∙h−1 (AQY: 3.03 % at 400 nm) and favorable H 2 production stability under visible light irradiation. This investigation not only provides a new idea for the regulation of interface charge transfer pathway but also offers new inspiration for the photocatalytic system's design with the synergistic impacts of 2D/2D VDW heterojunction and chemical bonds. [ABSTRACT FROM AUTHOR]

In this paper, using hydrothermal electrodeposition, we were able to synthesize a unique composite electrode material with a three-dimensional structure that is self-supporting. By growing nanoscale NiMnLDH-Co(OH) 2 on a nickel foam substrate, we created a solid and conductive skeleton with abundant reactive sites for electrochemical reactions. The resulting enhancement of electrochemical performance is due to the 3D layer of NiMnLDH-Co(OH) 2 which promotes efficient charge transfer. The combination of small nano-sheet Co(OH) 2 and NiMnLDH creates a strong synergistic effect that increases reaction kinetics. Additionally, the nickel foam substrate functions as a stabilizer, structural conductivity agent, and excellent conductive medium. [Display omitted] A self-supporting composite electrode material with a unique three-dimensional structure was synthesized by in-situ growth of nanoscale NiMnLDH-Co(OH) 2 on a nickel foam substrate via hydrothermal electrodeposition. The 3D layer of NiMnLDH-Co(OH) 2 provided abundant reactive sites for electrochemical reactions, ensuring a solid and conductive skeleton for charge transfer and resulting in significant enhancement of electrochemical performance. The composite material showed a strong synergistic effect between the small nano-sheet Co(OH) 2 and NiMnLDH, which promoted reaction kinetics, while the nickel foam substrate acted as a structural conductivity agent, stabilizer, and good conductive medium. The composite electrode showed impressive electrochemical performance, achieving a specific capacitance of 1870F g−1 at 1 A g−1 and retaining 87% capacitance after 3000 charge–discharge cycles, even at a high current density of 10 A g−1. Moreover, the resulting NiMnLDH-Co(OH) 2 //AC asymmetric supercapacitor (ASC) demonstrated remarkable specific energy of 58.2 Wh kg−1 at a specific power of 1200 W kg−1, along with outstanding cycle stability (89% capacitance retention after 5000 cycles at 10 A g−1). More importantly, DFT calculations reveal that NiMnLDH-Co(OH) 2 facilitates charge transfer, accelerating surface redox reactions and increasing specific capacitance. This study presents a promising approach towards designing and developing advanced electrode materials for high-performance supercapacitors. [ABSTRACT FROM AUTHOR]

[Display omitted] Construction of Z-scheme heterojunctions has been considered one superb method in promoting solar-assisted charge carrier separation of carbon-based materials to achieve efficient utilization of solar energy in hydrogen production and CO 2 reduction. One interesting concept in nanofabrication that has become trend recent years is nanoarchitectonics. A heterostructure photocatalyst constructed based on the idea of nanoarchitectonics using the combination of g-C 3 N 4 , metal and an additional semiconducting nanocomposite is investigated in this paper. Z-scheme tungsten oxide incorporated copper modified graphitic carbon nitride (WO x /Cu-g-C 3 N 4) heterostructures are fabricated via immobilization of WO x on Cu nanoparticles modified superior thin g-C 3 N 4 nanosheets. Mechano-chemical pre-reaction and a two-step high-temperature thermal polymerization process are the keys in attaining homogeneous distribution of Cu nanoparticles in g-C 3 N 4 nanosheets. The horizontal growth of homogeneously distributed WO x nanobelts on Cu modified g-C 3 N 4 (Cu-g-C 3 N 4) base via solvothermal synthesis is achieved. The photocatalytic performances of the heterostructures are evaluated through water splitting and CO 2 photoreduction measurements in full solar spectrum irradiation condition. The presence of Cu nanoparticles in the composite system improves charge transport between g-C 3 N 4 and WO x and thus enhances the photocatalytic performances (H 2 generation and CO 2 photoreduction) of the composite material, while the presence of WO x nanocomposites enhances light absorption of the composite material in the near infrared range. The synthesized heterostructure with optimized WO x to Cu-g-C 3 N 4 ratio and in case of no co-catalyst addition exhibits enhanced photocatalytic H 2 evolution (4560 μmolg-1h−1) as well as excellent CO 2 reduction rate (5.89 μmolg-1h−1 for CO generation). [ABSTRACT FROM AUTHOR]

[Display omitted] Porous nanospheres (PNSs) have great development prospects in the electrocatalysis field because of their structural characteristics, such as a large specific surface area. However, it is still a challenge to find a simple and energy-saving method for the controllable synthesis of PNS nanocatalysts. In this paper, a one-pot CTAC-assisted strategy was developed for the successful formation of PdPtAg PNSs with high porosity at room temperature. Benefitting from the unique structures, optimized composition, acceleration of charge transfer and enhanced resistance to CO poisoning, the PdPtAg PNSs displayed considerably improved electrocatalytic performance with high mass activity and stability toward the ethylene glycol oxidation reaction (EGOR) and glycerol oxidation reaction (GOR). The EGOR and GOR mass activities of PdPtAg were 5.00 A mg metal -1 and 3.06 A mg metal -1, which are 6.22 and 1.91 times that of commercial Pd/C, respectively. This work is expected to offer a new path for improving catalytic performance by simple design and adjustment of morphology. [ABSTRACT FROM AUTHOR]

[Display omitted] • Surface nitrogen vacancy is instrumental in the chemisorption and activation of H 2 O. • Surface nitrogen vacancy and extended photocarrier lifetime has improved H 2 production. • S-scheme band of AgI/g-C 3 N 4 is conjectured by the experiments and DFT calculations. AgI/g-C 3 N 4 S-scheme heterojunction with a unique electron transfer pathway was developed as a catalyst for H 2 evolution. We discussed the behavior of chemisorption and photoexcited charge carriers in photocatalytic reduction on the S-scheme AgI/g-C 3 N 4 heterojunction. It was demonstrated that the path of charge transfer mediated by S-scheme AgI/g-C 3 N 4 heterojunction was favorable for the improvement of electron utilization in photocatalysis. The advantage of S-scheme heterojunction was that the holes in the valence band (VB) of g-C 3 N 4 could recombine with the electrons in the conduction band (CB) of AgI due to the built-in electric field. Electrons on the CB of g-C 3 N 4 and holes on the VB of AgI were preserved for further photocatalytic reaction. Therefore, a distinctive electron transfer pathway was introduced in the S-scheme heterojunction. In addition, the lifetime of charge carriers was prolonged, and the reduced ability of electrons was increased as compared to reference g-C 3 N 4. It not only decreased the energy required for electron excitation, but also reduced the energy consumption for the charge transfer. This paper provided a new strategy to improve the utilization of photogenerated electrons and chemisorption of water for photocatalytic H 2 O splitting. [ABSTRACT FROM AUTHOR]

A novel 2D/0D hybrid photocatalyst composed of porous Co x P nanosheets and Mn 0.35 Cd 0.65 S nanoparticles has been developed, and presents efficient photocatalytic H 2 evolution from water splitting. [Display omitted] • Porous Co x P nanosheets were prepared by phosphating Co(OH) 2 nanosheets. • 2D/0D Co x P/Mn 0.35 Cd 0.65 S were fabricated using a simple solution-phase method. • Co x P/Mn 0.35 Cd 0.65 S exhibited dramatically enhanced photoactivity for H 2 generation. • The behavior of photoexcited charge carriers in Co x P/Mn 0.35 Cd 0.65 S were investigated. Incorporating 2D transition-metal phosphides into visible-light-driven semiconductors is fascinating for advancing novel photocatalysts. In this paper, porous Co x P nanosheets prepared by phosphating Co(OH) 2 nanosheets are coupled with Mn 0.35 Cd 0.65 S nanoparticles for significantly boosted photocatalytic H 2 evolution performance. The optimal Co x P/Mn 0.35 Cd 0.65 S hybrids show an excellent visible-light H 2 production rate of 7188.9 μmol g−1h−1 upon visible light with an apparent quantum yield (AQY) of 18.9% at 420 nm. The H 2 production rate of the 5% Co x P/Mn 0.35 Cd 0.65 S sample is about 257 times bare CdS and even 18 times higher than pristine Mn 0.35 Cd 0.65 S. This dramatic photocatalytic H 2 generation activity is mainly ascribed to the efficient charge transfer and abundant active sites by introducing the porous Co x P nanosheets. The photocatalytic mechanism of the Co x P/Mn 0.35 Cd 0.65 S composites is investigated by the photoluminescence (PL), time-resolved photoluminescence (TRPL), electrochemical, and photoelectrochemical (PEC) tests. This work presents a viable strategy to design a 2D/0D hybrid system containing porous cobalt phosphides nanosheets and MnCdS solid solutions for noble-metal-free photocatalytic application. [ABSTRACT FROM AUTHOR]

[Display omitted] • The porous few-layer bimetallic co-doped g-C 3 N 4 is prepared via a facile bottom-up method. • The bimetallic synergetic regulating effect on the electronic structure can be produced in Co/Ni-g-C 3 N 4. • The superior performance results from the improved charge separation efficiency and visible light harvestability. • This work provides meritorious guidance for new bimetallic co-doped g-C 3 N 4 photocatalysts. The low specific surface area and low charge transfer efficiency of conventional graphite carbon nitride (g-C 3 N 4) are the main obstacles to its application in photocatalytic CO 2 reduction. In this paper, graphite carbon nitride was protonated by phosphoric acid (H 3 PO 4), and a new few-layer porous carbon nitride was prepared by intercalation polymerization with doping bimetal in the cavity of g-C 3 N 4. Under visible light irradiation, the CO formation rate of Co/Ni co-doped g-C 3 N 4 can reach 13.55 μmol g−1 h−1, which was 3.9 times higher than that of g-C 3 N 4 (3.49 μmol g−1 h−1). The density functional theory (DFT) calculations showed that the addition of Co and Ni in the cavity of g-C 3 N 4 can induce bimetallic synergistic regulation of the electronic structure, thus improving the separation efficiency of charges and visible light capture ability of g-C 3 N 4. Our work has great reference value for designing and synthesizing novel bimetallic co-doped g-C 3 N 4 photocatalytic materials. [ABSTRACT FROM AUTHOR]

Here, a novel Step-scheme MoS 2 /Bi 4 O 5 Br 2 heterojunction is successfully prepared. Takeing the advantages of the higher efficiency of separation and transfer of charge carrier, light caputer ability and stronger redox capacity of electron and hole in the unique Step-scheme transfer pathway between the MoS 2 and Bi 4 O 5 Br 2. The photocatalytic system exhibited superior photocatlaytic organic pollutant degradation and disinfection which paves a novel strategy for exploring the Bi 4 O 5 Br 2 -based photocatalysts and appling that in environmental remediation. [Display omitted] • Novel S-scheme MoS 2 /Bi 4 O 5 Br 2 composites were synthesized. • MoS 2 /Bi 4 O 5 Br 2 exhibited excellent disinfection and RhB removal behavior. • h+, ·O 2 – and ·OH were the main active species over MoS 2 /Bi 4 O 5 Br 2 composites. • Cell-membrane disruption and Leakage of bio-molecular from bacteria induce its final death. In this paper, a novel Step-scheme MoS 2 /Bi 4 O 5 Br 2 heterojunction was fabricated through the in-situ mechanical agitation method and the photocatalytic activity of that was examined by the photocatalytic degradation Rhodamine B (RhB) and inactivation of E.coli under visible light irradiation (λ > 420 nm). The Step-scheme MoS 2 /Bi 4 O 5 Br 2 heterojunctions displayed the enhanced photocatalytic ability compared to pure Bi 4 O 5 Br 2 and MoS 2 and the MoS 2 /Bi 4 O 5 Br 2 -3% (MS/BOB-3) heterojunction exhibited the strongest photocatalytic activity which can completely inactivate the 1 × 107 cfu/mL with 180 min and degrade RhB (10 mg/L) with 24 min visible light irradiation, respectively. The photocatalytic mechanism of the MoS 2 /Bi 4 O 5 Br 2 heterojunction is was attributed to the generated active species (h+, ·O 2 − and ·OH) which can effectively destroy RhB molecular and cell-membrane of bacterial as demonstrated by multiple techniques such as LC-MS and fluorescence stain. Additionally, characterization results disclosed that the transfer pathway of charge carriers of constructed MoS 2 /Bi 4 O 5 Br 2 heterojunction followed the Step-scheme channel, which not only facilitated the separation and migration of the photo-generated charge carriers, but also improved the light absorption ability of the samples and resulting in the promoted photocatalytic performance of MoS 2 /Bi 4 O 5 Br 2 heterojunction. This work paves a new idea to develop novel bismuth oxyhalide-based photocatalytic system for wastewater purification. [ABSTRACT FROM AUTHOR]

[Display omitted] As a renewable green energy, hydrogen has received widespread attention due to its huge potential in solving energy shortages and environment pollution. In this paper, a one-step solvothermal method was applied to grow ultra-thin g-C 3 N 4 (UCN) nanosheets and NiS nanoparticles on the surface of ZnIn 2 S 4 (ZIS). A ternary NiS/ZnIn 2 S 4 /ultra-thin-g-C 3 N 4 composite material with dual high-speed charge transfer channels was constructed for the advancement of the photocatalytic H 2 generation. The optimal ternary catalyst 1.5wt.%NiS/ZnIn 2 S 4 /ultra-thin-g-C 3 N 4 (NiS/ZIS/UCN) achieved a H 2 evolution yield reached to 5.02 mmolg−1h−1, which was 5.23 times superior than that of pristine ZnIn 2 S 4 (0.96 mmolg−1h−1) and even outperform than that of the best precious metal modified 3.0 wt%Pt/ZnIn 2 S 4 (4.08 mmolg−1h−1). The AQY at 420 nm could be achieved as high as 30.5%. The increased photocatalytic performance of NiS/ZIS/UCN could be ascribed to the type-I heterojunctions between intimated ZIS and UCN. In addition, NiS co-catalyst with large quantity of H 2 evolution sites, could result in efficient photo-induced charges separation and migration. Furthermore, the NiS/ZIS/UCN composite exhibited excellent H 2 evolution stability and recyclability. This work would also offer a reference for the design and synthesis of ternary co-catalyst with heterojunction composite for green energy conversion. [ABSTRACT FROM AUTHOR]

[Display omitted] The deposition of the CaCO 3 scale in circulating cooling water is a common and serious concern in the industry, which hinders the heat transfer, reduces water flow and blocks membrane filters. This paper aims at studying the effect of the γ-Fe 2 O 3 , Fe 2 (MoO 4) 3 ·γ-Fe 2 O 3 and FePO 4 ·γ-Fe 2 O 3 passive films on CaCO 3 scale deposition on Q235 steel by electrochemical methods, including linear sweep voltammetry (LSV), chronoamperometry and electrochemical impedance spectroscopy (EIS) tests. The scale and corrosion inhibition performance of the passive films was evaluated by the residual current density (i r) and charge transfer resistance (R ct) values. Electrochemical results suggested that the passive films could inhibit corrosion and reduce the CaCO 3 scale deposition on Q235 steel and the FePO 4 ·γ-Fe 2 O 3 complex passive film showed the best anti-scaling effect. Scanning electron microscope (SEM) and X-ray diffractometer (XRD) tests showed that the passive films could lead to a decrease in the proportion of aragonite to calcite under cathodic water reduction conditions and the composition of the FePO 4 ·γ-Fe 2 O 3 complex passive film could deform the CaCO 3 crystal. [ABSTRACT FROM AUTHOR]

Construction of Schottky junctions based DUT-67 and Pd nanosheet with enhanced charge carrier separation efficiency for efficient photoreduction of CO 2. [Display omitted] • DUT-67 decorated with Pd nanosheet was prepared. • 0.3-Pd/DUT-67 had considerable photocatalytic CO 2 reduction to CO efficiency of 48.6 μmol g−1. • Schottky barrier at Pd/DUT-67 interface boosts separation of electron-hole pairs. The separation, transfer and recombination of charge often affect the rate of photocatalytic reduction of CO 2. Schottky junctions can promote the rapid separation of space charge. Therefore, in this paper, Pd nanosheets were grown on the surface of DUT-67 by a hydrothermal method, and a Schottky junction was constructed between DUT-67 and Pd. Under the action of the Schottky junction, the CO yield of 0.3-Pd/DUT-67 reached 12.15 μmol/g/h, which was 17 times higher than that of DUT-67. Efficient charge transfer was demonstrated in photochemical experiments. The large specific surface area and the increased light utilization rate also contributed to the increase in the CO 2 reduction efficiency. In addition, the mechanism of Pd/DUT-67 photocatalytic reduction of CO 2 was proposed. [ABSTRACT FROM AUTHOR]

• p-TCN@U6-X composites were prepared by in-situ growth of UiO-66-NH 2 on the p-TCN. • Composites exhibit good photocatalytic hydrogen production and benzylamine oxidation. • The effective charge separation and transfer happened in the p-TCN@U6-X system. It is still a challenge to evolve visible light photocatalysts that possess both efficient oxidation and reduction capabilities. In this paper, phosphorus-doped tubular carbon nitride@UiO-66-NH 2 (p-TCN@U6-X) composites were prepared by in-situ load of UiO-66-NH 2 on the surface of p-TCN based on solvothermal method, which exhibit excellent photocatalytic oxidation and reduction ability. As a result, under visible light irradiation (λ > 420 nm), the photocatalytic H 2 production performance of p-TCN@U6-3 reached 2628 μmol g−1h−l, which was 8.19 and 5.36 times higher than that of p-TCN and UiO-66-NH 2 , respectively. Meanwhile, p-TCN@U6-3 also exhibited well selectivity rate (99%) and conversion rate (98%) for oxidative coupling of amine compounds. The high photocatalytic activities can be assigned to the improved visible light adsorption resulted from the tubular structure of p-TCN and enhanced electrical conductivity because of the phosphorus doping in p-TCN. Furthermore, UiO-66-NH 2 plays the role of co-catalyst and active centers in the photocatalytic system to synergistically catalyze the reactions. Transient photocurrent spectra, steady-state photoluminescence (PL) and time-resolved photoluminescence (TRPL) further prove the more effective charge separation and transfer happened in the p-TCN@U6-X system compared with sole p-TCN and UiO-66-NH 2 , respectively. This work provides an effective method for creating novel carbon nitride-based photocatalytic systems with efficient capability for photocatalytic oxidation and reduction. [ABSTRACT FROM AUTHOR]

In this paper, we designed and prepared a novel metal organic framework (MOF)/holey graphene (HG) composites as electrode materials for electrochemistry and capacitive deionization (CDI). The MOF nanoparticles were attached to the surface of the HG sheets to form layered porous structure, which promoted the transport of ions and electrons in the electrode/electrolyte interfaces. Additionally, the synergistic effect of these composite electrodes, which combined pseudocapacitance performance of MOF and the high conductivity of graphene, contributed to enhancing the performance of electrochemistry and CDI. The MOF/HG-2 exhibited high capacitances of 526 F g−1 at current rates of 0.1 A g−1, low charge transfer resistance of 0.53 Ω, and excellent cycling stability (retention of about 90.3% after 5000 cycles at 2 A g−1). As electrode materials for CDI, the MOF/HG-2 displayed a remarkable electrosorption capacity of 39.6 mg g−1 with initial salt concentration of 800 mg L−1, and there was no obvious attenuation after 20 CDI regeneration cycles. These results confirmed that MOF/HG was a promising electrode material for the actual application of CDI. [ABSTRACT FROM AUTHOR]

• The Mn 3 O 4 -Fe 3 O 4 @C hybrids with various architectures were synthesized. • The structure of hybrids is controllable by adjusting Fe content in the carbon fiber. • The Mn 3 O 4 -Fe 3 O 4 @C with oolite-like particles presents superior capacitor erformance. Controlling the morphology and structure of nanomaterials is of great importance for enhancing the electrochemical properties. In the paper, Mn 3 O 4 -Fe 3 O 4 @C hybrids with different architectures were synthesized by incubation of electrospun FeOx-containing carbon fiber (Fe-CNF) in KMnO 4 solution followed by annealing. The presence of FeOx on the CNF plays a vital role in determining the morphology and structure of the final hybrids, and the Mn 3 O 4 -Fe 3 O 4 @C hybrids with half-tube, tube and oolite-filled fibers are formed conveniently by tuning Fe content in the carbon fiber precursor. The good conductivity of fiber and various redox states of Mn and Fe afford the facile charge transfer and excellent reversible redox properties, thus enhancing the capacitor performance. The oolite-filled Mn 3 O 4 -Fe 3 O 4 @C with tubular structure exhibited a high specific capacitance of 178 F g−1 at a discharge rate of 1 A g−1. This capacitor electrode has an excellent cyclic stability with 95% capacitance retention after 1000 cycles at 3 A g−1. This work provides a very simple strategy to tune the unique nanostructures of metal oxide on Fe-CNF for high-performance supercapacitor application in the future. [ABSTRACT FROM AUTHOR]

The deposition of CaCO 3 scale in circulating cooling water on metal surface is a major concern in industry. This paper focuses on the feasibility of electrochemical methods to study the scale inhibition performance of 1-hydroxyethylidene-1,1-diphosphonic acid (HEDP) and 2-phosphonobutane-1,2,4-tricarboxylic acid (PBTCA), Polyacrylic Acid (PAA), including linear sweep voltammetry, chronoamperometry, and electrochemical impedance spectroscopy (EIS). In addition, the coverage, morphology and structure of deposited CaCO 3 crystal on titanium alloy surface in the absence and presence of inhibitors were investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM). A new method for calculating the efficiency of scale inhibitors was proposed so that it can be calculated by using the change in residual current density (i r). In order to prove the feasibility and accuracy of such method, the efficiencies of inhibitors were evaluated using i r and charge transfer resistance (R ct), respectively. In addition, molecular dynamics (MD) simulations were performed to evaluate the interaction between the scale inhibitor molecule and the CaCO 3 crystal. The experimental results show that both the residual current density obtained by chronoamperometry and the charge transfer resistance obtained by electrochemical impedance spectroscopy can be used to evaluate the efficiency of scale inhibitors, and there is high consistency from the calculation results. It is also confirmed by X-ray diffraction and scanning electron microscopy studies that the presence of inhibitor reduces the surface coverage of CaCO 3 at metal electrode and that the crystal structure of CaCO 3 is transformed from the original aragonite into the most unstable vaterite. The best inhibition efficiency of PBTCA for CaCO 3 deposit is confirmed by the results of MD simulations. [ABSTRACT FROM AUTHOR]

• 3-D Ag/ZnO@CF photocatalysts with enhanced mass transfer were fabricated. • Hierarchical structure and loaded cocatalysts improved the photocarriers separation. • Phenol-Cr (VI) ester contributed to the homogeneous self-elimination of pollutants. • Synergistic removal of phenol and Cr(VI) by hetero- and homogeneous photocatalysis. Synergistic photocatalysis offers great potential for simultaneously treating organic and heavy metal pollutants. Although considerable progress has been made, this technology is seriously restricted by the poor photoactivity of heterogeneous catalysts, and the contribution from homogeneous intermoleculars has been overlooked. In this paper, the Ag/ZnO@CF with 3-D hierarchical porous structure was fabricated and used to synergistically remove phenol and Cr(VI) from water. Due to the enhanced mass transfer and cocatalysts-facilitated charge separation, 3-D photocatalysts exhibited significantly improved activity for heterogeneous photocatalysis. Furthermore, both experimental characterizations and DFT calculations evidenced the formation of phenol-chromate(VI) esters with ligand-to-metal charge transfer from benzene ring to central chromium ion under photoexcitation. Thereafter, the effects of heterogeneous and homogeneous photocatalysis on the treatment efficiency of multiplex pollutants were investigated. In an ideal scenario, 2.4 and 2.3 times higher phenol and Cr(VI) removal rate were achieved compared to single catalytic reactions. This work not only offers new material strategy for photocatalyst exploration, but also provides new insights into the multiphase homogeneous catalysis contributed by intermolecular interactions. [ABSTRACT FROM AUTHOR]

Low dimensional nanomaterials have emerged as candidates for gas sensors owing to their unique size-dependent properties. In this paper, Bi 2 S 3 nanobelts were synthesized via a facile solvothermal process and spin-coated onto alumina substrates at room temperature. The conductometric devices can even sensitively response to the relatively low concentrations of NO 2 at room temperature, and their sensing performance can be effectively enhanced by the ligand exchange treatment with inorganic salts. The Pb(NO 3 ) 2 -treated device exhibited superior sensing performance of 58.8 under 5 ppm NO 2 at room-temperature, with the response and recovery time of 28 and 106 s. The competitive adsorption of NO 2 against O 2 on Bi 2 S 3 nanobelts, with the enhancement both in gas adsorption and charge transfer caused by the porous network of the very thin Bi 2 S 3 nanobelts, can be a reasonable explanation for the improved performance at room temperature. Their sensitive room-temperature response behaviors combined with the excellent solution processability, made Bi 2 S 3 nanobelts very attractive for the construction of low-cost gas sensors with lower power consumption. [ABSTRACT FROM AUTHOR]

The solid-state Z-scheme trinary/binary heterostructures show the advantage of utilizing the high-energy photogenerated charge carriers in photocatalysis. However, the key factors controlling such Z-scheme in the binary heterostructures are still unclear. In this paper, we showed that oxygen vacancies could act as an interface electron transfer mediator to promote the direct Z-scheme charge transfer process in binary semiconductor heterostructures of CdS/ZnS. Increasing the concentration of surface oxygen vacancies of ZnO crystal can greatly enhance photocatalytic hydrogen generation of CdS/ZnO heterostructure. This was attributed to the strengthened direct Z-scheme charge transfer process in CdS/ZnO, as evidenced by steady-state/time-resolved photoluminescence spectroscopy and selective photodeposition of metal particles on the heterostructure. [ABSTRACT FROM AUTHOR]

This paper reports a novel procedure using nanosomes, made of bola-hydroxyl and mercapto-palmitic acids, for the production of gold clusters with robust luminescent emissions and very large Stokes shifts. It shows that these results cannot be explained by the currently accepted mechanism based on ligand-to-metal charge transfer absorptions involving electron-rich ligands attached to the cluster core. Exhaustive characterization of the cluster samples using Mass Spectrometry, HR-TEM/STEM, XPS, EXAFS, and steady-state and time-resolved luminescence allows to deduce that a mixture of two cluster sizes, having non-closed shell electronic configurations, are firstly generated inside the nanosome compartments due to the difference in bonding strength of the two types of terminal groups in the fatty acids. This initial bimodal cluster size distribution slowly evolves into very stable, closed-shell Au cluster complexes (Au 6 –Au 16 and Au 5 –Au 14 ) responsible for the observed luminescent properties. The very small (≈1.2 nm) synthesized cluster complexes are water soluble and suitable to be used for the conjugation of biomolecules (through the terminal COO − groups) making these systems very attractive as biomarkers and offering, at the same time, a novel general strategy of fabricating stable atom-level quantum dots with large Stokes shifts of great importance in many sensor applications. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we present the development of a method to accurately measure the positive and negative charge distribution of nanosized aerosols using a tandem differential mobility analyzer (TDMA) system. From the series of TDMA measurements, the charge fraction of nanosized aerosol particles was obtained as a function of equivalent mobility particle diameter ranging from 50 to 200 nm. The capability of this new approach was implemented by sampling from a laminar diffusion flame which provides a source of highly charged particles due to naturally occurring flame ionization process. The results from the TDMA measurement provide the charge distribution of nanosized aerosols which we found to be in reasonable agreement with Boltzmann equilibrium charge distribution theory and a theory based upon charge population balance equation (PBE) combined with Fuchs theory (N.A. Fuchs, Geofis. Pura Appl. 56 (1963) 185). The theoretically estimated charge distribution of aerosol particles based on the PBE provides insight into the charging processes of nanosized aerosols surrounded by bipolar ions and electrons, and agree well with the TDMA results. [Copyright &y& Elsevier]