Search

Electrochemical nitrogen reduction reaction (NRR) has been identified as a prospective alternative for sustainable ammonia production. Developing cost-effective and highly efficient electrocatalysts is critical for NRR under ambient conditions. Herein, the hierarchical cobalt-molybdenum bimetallic sulfide (CoS2/MoS2) flower-like heterostructure assembled from well-aligned nanosheets has been easily fabricated through a one-step strategy. The efficient synergy between different components and the formation of heterostructure in CoS2/MoS2 nanosheets with abundant active sites makes the non-noble metal catalyst CoS2/MoS2 highly effective in NRR, with a high NH3 yield rate (38.61 μg h–1 mgcat.–1), Faradaic efficiency (34.66%), high selectivity (no formation of hydrazine) and excellent long-term stability in 1.0 mol L–1 K2SO4 electrolyte (pH=3.5) at − 0.25 V versus the reversible hydrogen electrode (vs. RHE) under ambient conditions, exceeding much recently reported cobalt- and molybdenum--based materials, even catch up with some noble-metal-based catalyst. Density functional theory (DFT) calculation indicates that the formation of N2H* species on CoS2(200)/MoS2(002) is the rate-determining step via both the alternating and distal pathways with the maximum ΔG values (1.35 eV). These results open up opportunities for the development of efficient non-precious bimetal-based catalysts for NRR.

Defective cross linked nickel cobalt sulfide sheets dominated by phosphorus anions and a hetero interface were designed. The catalyst possesses surprising HER properties with low overpotentials and long term stability.

Highly efficient catalysts with enough selectivity and stability are essential for electrochemical nitrogen reduction reaction (e-NRR) that has been considered as a green and sustainable route for synthesis of NH3. In this work, a series of three-dimensional (3D) porous iron foam (abbreviated as IF) self-supported FeS2-MoS2 bimetallic hybrid materials, denoted as FeS2-MoS2@IFx, x = 100, 200, 300, and 400, were designed and synthesized and then directly used as the electrode for the NRR. Interestingly, the IF serving as a slow-releasing iron source together with polyoxomolybdates (NH4)6Mo7O24·4H2O as a Mo source were sulfurized in the presence of thiourea to form self-supported FeS2-MoS2 on IF (abbreviated as FeS2-MoS2@IF200) as an efficient electrocatalyst. Further material characterizations of FeS2-MoS2@IF200 show that flower cluster-like FeS2-MoS2 grows on the 3D skeleton of IF, consisting of interconnected and staggered nanosheets with mesoporous structures. The unique 3D porous structure of FeS2-MoS2@IF together with synergy and interface interactions of bimetallic sulfides would make FeS2-MoS2@IF possess favorable electron transfer tunnels and expose abundant intrinsic active sites in the e-NRR. It is confirmed that synthesized FeS2-MoS2@IF200 shows a remarkable NH3 production rate of 7.1 ×10-10 mol s-1 cm-2 at -0.5 V versus the reversible hydrogen electrode (vs RHE) and an optimal faradaic efficiency of 4.6% at -0.3 V (vs RHE) with outstanding electrochemical and structural stability.

Oxygen defects and hollow structures positively impact pseudocapacitive properties of diffusion/surface-controlled processes, a component of critical importance when building high-performance supercapacitors. Hence, we fabricated hollow nickel/cobalt molybdate rods with O-defects (D-H-NiMoO 4 @CoMoO 4 ) via a soft-template and partial reduction method, enhancing D-H-NiMoO 4 @CoMoO 4 's electrochemical performance, yielding a specific capacitance of 1329 F g -1 , and demonstrating excellent durability with 95.8% capacity retention after 3000 cycles. D-H-NiMoO 4 @CoMoO 4 was used as the positive electrode to construct an asymmetric supercapacitor, displaying an energy density of up to 34.13 W h kg -1 and demonstrating good predisposition towards practical applications. This work presents an effective approach to fabricate and use hollow nickel/cobalt molybdate rods with O-defects as pseudo-capacitor material for high-performance capacitive energy storage devices.

Multidimensional fabrication of metal-organic frameworks (MOFs) into multilevel channel integrated devices are in high demanded for Li-S separators. Such separators have advantages in pore-engineering that might fulfill requirements such as intercepting the diffusing polysulfides and improving the Li+ /electrolyte transfer in Li-S batteries. However, most reported works focus on the roles of MOFs as ionic sieves for polysulfides while offering limited investigation on the tuning of Li+ transfer across the separators. A photoinduced heat-assisted processing strategy is proposed to fabricate MOFs into multidimensional devices (e.g., hollow/Janus fibers, double-or triple-layer membranes). For the first time, a triple-layer separator with stepped-channels has been designed and demonstrated as a powerful separator with outstanding specific capacity (1365.0 mAh g-1 ) and cycling performance (0.03 % fading per cycle from 100th to 700th cycle), which is superior to single/double-layer and commercial separators. The findings may expedite the development of MOF-based membranes and extend the scope of MOFs in energy-storage technologies.

To research the application of polyoxometalates (POMs)-based supramolecular crystalline materials in supercapacitors, two new compounds, H3PWVI12O40·(BPE)2.5·3H2O(1) and H3PMoVI12O40·(BPE)2.5·3H2O (2) (BPE = 1,2-Bis(4-pyridyl)ethylene) have been synthesized by a one-step hydrothermal method. Their structures are determined by single-crystal X-ray diffraction analysis and further characterized by FTIR spectroscopy, powder X-ray diffraction, and bond valence sum analysis. The POMs cluster ([H3PWVI12O40] or [H3PMoVI12O40]) acts as a connector to connect five BPE units through hydrogen bonds, generating a three-dimensional structure. The capacitance performance of these two compounds is tested by cyclic voltammetry, galvanostatic charge–discharge, and electrochemical impedance spectroscopy. Compared with compound 1 and parent H3PMoVI12O40, compound 2 shows better electrochemical performances with a capacitance of 137.5 F g–1 at 2 A g–1. Compound 2 also has good cycle stability at a current density of 10 A g–1 and still has an initial capacitance of 92% after 1000 cycles. This work shows that hybrid supramolecular crystal materials based on polyoxometalates may provide an alternative way to improve the performance of POMs-based capacitor electrode materials. Two POMs-based supramolecular crystalline materials were synthesized by a hydrothermal method. The supercapacitor performance of these two compounds is better than their parents POMs(PW12 and PMo12). Among them, compound 2 displays specific capacitance (137.5 F g–1 at 2 A g–1) and better cycle stability (92.0% after 1000 cycles).

A new polyoxometelate (POM)-based host–guest supramolecular network, [MnII(L)3]2(SiW12O40)·4H2O (L = 3-pyraziny-1,2,4-triazole), was synthesized by the hydrothermal reaction, and characterized by single crystal X-ray diffraction, infrared spectroscopy, powder X-ray diffraction and solid-state ultraviolet visible diffuse reflection. The compound is composed of Keggin type [SiW12O40]2− anion (SiW12) and manganese–L complex. A structural feature for the compound is that the manganese–L complexes are arranged to construct a host–guest network with two types of channels (the small and big ones), and the [SiW12O40]2− as guests are only encapsulated in holes of the big channels. The whole network is still highly open due to possessing vacant channels and therefore H2O and H+ can diffuse through these vacant channels with ease. Hence, it is a favourite for imposing more photo-active sites ([SiW12O40]2− and Mn) for H2O and H+. Consequently, the photocatalytic hydrogen productivity of the title compound can reach 337.76 μmol−1 g−1 h−1, which is much higher than the 6.31 μmol g−1 h−1 of its parent (TBA)4SiW12O40 POM under identical experimental conditions.

In this work, a novel composite based on N-Doped mesoporous carbon nanospheres and graphene (N-MCS@graphene) is successfully designed and constructed for rutin (RT) detection. The ordered mesoporous architecture offers high specific surface area, and open pores that lead to amplified target/receptor interfaces and a fast diffusion path for the analyte. Meanwhile, graphene can facilitate charge transfer and provide rich active sites. Amperometry and cyclic voltammetry are used to investigate the electrochemical properties and sensing ability of a N-MCS@graphene modified electrode. The results indicate that the N-MCS@graphene electrode shows a greatly enhanced electrochemical response to RT, and possesses great sensing performance towards RT with the linear range of 0.5–189 μM, the detection limit of 0.05 μM, and favorable selectivity towards common interfering species. Moreover, the composite can be used for the determination of RT in human serum with satisfactory results.

Eliminating the use of precious metals as cocatalysts and using visible light are two important aspects in the field of photocatalytic H2 evolution with polyoxometalates (POMs) as photosensitizers. Here we present two new POM-based materials: [CuII5(2-ptz)6(H2O)4(GeW12O40)]·4H2O (1) and [CuI2(ppz)4][H2GeW12O40]·8H2O (2) (2-ptz = 5-(2-pyridyl) tetrazole, ppz = 3-(pyrid-4-yl) pyrazole) synthesized with the Keggin type [GeW12O40]4− (GeW12) polyanion and copper-azole complexes. The optimum photocatalytic H2 evolution rate of compound 1 without a noble metal cocatalyst is 3813 μmol g−1 h−1, which is 7.6 times higher than that of compound 2 and more than 27 times higher than that of bare GeW12 polyanions. The improved photocatalytic H2 evolution rate of compound 1 is mainly attributed to: (i) the formation of stable heteropoly blue species that can absorb visible light, (ii) the large differences in the reduction potentials of the GeW12 polyanion and the copper complexes that inhibit photogenerated electron–hole pair recombination and (iii) the good dispersion of the GeW12 polyanions, thanks to the presence of [CuII5(2-ptz)6(H2O)4]n4n+ layers that preclude their aggregation. To the best of our knowledge, compound 1 is the photosensitizer for H2 evolution with the highest photocatalytic performance of all the classical POM-based materials.

Objective: The objective was to investigate the anti-inflammatory effects of salidroside through the PI3K/Akt signaling pathway and its protective effects on acute hypoxia-induced myocardial injury in rats. Methods: A total of 24 healthy Sprague-Dawley male rats were selected as the experimental subjects. All rats were divided into 4 groups by using the random number table method, with 6 rats in each group. The groups included the normal control group, the salidroside group, the hypobaric hypoxia group, and the hypobaric hypoxia + salidroside group. Rats in the salidroside group were fed in the original animal laboratory and were intragastrically administered with salidroside every morning at a dosage of 35 mg/kg. Rats in the normal control group were intragastrically administered with an equal dosage of saline. Rats in the hypobaric hypoxia + salidroside group were intragastrically administered with salidroside every morning at a dosage of 35 mg/kg, who were fed in the hypoxic experiment module for animals. The altitude was increased to 4000 m, and the rats were kept in the module for 24 h. Rats in the hypobaric hypoxia group were intragastrically administered with an equal dosage of saline in the same environment, and the altitude was increased to 4000 m after administration. Parameters of blood gas analysis, histopathological changes in cardiac tissues, cardiac indexes, and inflammatory factors IL-6 and TNF-α levels of rats in groups were compared. Results: 1. The cardiac indexes of rats in groups were compared. The differences between the hypobaric hypoxia group and the hypobaric hypoxia + salidroside group were statistically significant (P

A three-dimensional (3D) hollow CoWO4 composite grown on Ni-foam (3D-H CoWO4 /NF) based on a flower-like metal-organic framework (MOF) is designed by utilizing a facile dipping and hydrothermal approach. The 3D-H CoWO4 /NF not only possesses large specific areas and rich active sites, but also accommodates volume expansion/contraction during charge/discharge processes. In addition, the unique structure facilitates fast electron/ion transport of 3D-H CoWO4 /NF. Meanwhile, a series of characterization measurements demonstrate the appropriate morphology and excellent electrochemical performance of the material. The 3D-H CoWO4 /NF possesses a high specific capacitance of 1395 F g-1 , an excellent cycle stability with 89% retention after 3000 cycles and superior rate property. Furthermore, the 3D-H CoWO4 /NF can be used as a cathode to configurate an asymmetric supercapacitor (ASC), and 3D-H CoWO4 /NF//AC shows a good energy density (29.0 W h kg-1 ). This work provides a facile method for the preparation of 3D-hollow electrode materials with high electrochemical capability for advanced energy storage devices.

Tibetan monks have a special way of life and food habits, however, little is known about their dyslipidemia. This study aimed to investigate the prevalence of dyslipidemia and risk factors of this population. A cross-sectional study of dyslipidemia was conducted in 876 Tibetan monks and 912 local residents in the same area. All subjects underwent interviews and physical examinations. The total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and triglycerides (TG) of the subjects were analyzed. Compared to local residents, the overall prevalence of dyslipidemia in monks was 29.5%, which was significantly lower (p

Binary transition metal oxides as electroactive materials have continuously aroused grumous attention due to their high theoretical specific capacitance, high valtage window, and multiple oxidation states. However, the tiny specific surface area, poor conductivity and unsatisfactory cycle stability limit their practical application. Hence, a synthetic strategy is designed to fabricate a dual-tasking hollow cube nickel ferrite (NiFe2O4) - based composite (NiFe2O4-NiCo-LDH@rGO) with hierarchical structure. The composite is constructed by firstly preparing hollow NiFe2O4 from cube-like Ni - Fe bimetallic organic framework (NiFe-MOF), and then integrating nickel cobalt layered double hydroxide (NiCo-LDH) nanowires, together with reduced graphene oxide (rGO) via pyrolysis in conjuction with hydrothermal method. The NiFe2O4 possessing cubic hollow structure contributes to a huge accessible surface area, meanwhile alleviates large volume expansion/contraction effect, which facilitates suffcient permeation of the electrolyte and rapid ion/charge transport, and results in high cycling stability. The introduction of layered NiCo-LDH results in hierarchical structure and thus offers maximum contact areas with electrolyte, which heightens the specific capacitance of obtained composite and enhances the electro-catlytic activity towards oxidation of glucose. Furthermore, rGO layer greatly improves the electrical conductivity and ion diffusion/transport capability of composite. Benefiting from the unique structure and individual components of NiFe2O4-NiCo-LDH@rGO composite, the electrode delivers a high specific capacitance (750 C g−1) and superb durability. Simultaneously, the asymmetrical device based on NiFe2O4-NiCo-LDH@rGO as positive electrode delivers remarkable energy density (50 Wh kg−1). Moreover, NiFe2O4-NiCo-LDH@rGO exhibits good sensing performance with a sensitivity of 111.86 µA/µM cm−2, the wide linear range of 3.500 × 10−5 − 4.525 × 10−3 M, and the detection limit of 12.94 × 10−6 M with a signal to noise ratio of 3. Consequently, the NiFe2O4-NiCo-LDH@rGO could provide a prospective notion constructing bifunctional materials with hollow-cube hierarchical structure in the field of supercapacitors and electrochemical sensors.

The development of high-efficiency noble-metal-free catalysts for the electrochemical nitrogen reduction reaction (NRR) to ammonia under ambient conditions has great significance in fertilizer production and energy storage. Considering the major role of Mo-nitrogenase with the FeMo cofactor in the biological N2 fixation process, the design and preparation of Mo and Fe bi-active metal based hybrid materials for the NRR under ambient conditions is proposed in this work. By using PMo12@MOF-100(Fe)@PVP (polyvinylpyrrolidone) as the precursor, two cost efficient FeMo-based electrocatalysts Fe1.89Mo4.11O7/FeS2@C and FeMoO4/FeS2@C were designed and fabricated for the NRR under room temperature and pressure conditions (RTP) via the easy-to-implement hydrothermal sulfuration method. The experiment results confirm that Fe1.89Mo4.11O7/FeS2@C (NH3 yield rate of 105.3 μg h−1 mgcat.−1, FE of 54.7% at −0.4 V vs. RHE) is more efficient towards the NRR than FeMoO4/FeS2@C (NH3 yield of 51.0 μg h−1 mgcat.−1, FE of 43.9% at −0.5 V vs. RHE) in acidic electrolytes; moreover they are all superior to most of the electrocatalysts reported to date. Further electrocatalysis of Fe1.89Mo4.11O7/FeS2@C in alkaline electrolytes (NH3 yield of 86.3 μg h−1 mgcat.−1, FE of 53.6% at −0.4 V vs. RHE) reveals the extensive NRR catalytic activity of this hybrid material. Density functional theory (DFT) calculation indicates that the NRR on Fe1.89Mo4.11O7/FeS2 has optimized nitrogen binding which facilitates the fast kinetics process through an enzymatic mechanism, and the protonation of N2 to form *N2H species is the potential-determining step (PDS) with the maximum ΔG values (+0.61 eV). This work opens up a significant opportunity to develop a family of efficient and robust FeMo-based electrocatalysts for the NRR under ambient conditions by using polyoxometalate-based metal–organic frameworks (POMOFs) as precursors by tuning metal sources.

Four new noble metal-free hybrids are reported with a maximum photocatalytic hydrogen evolution rate of 12245.59 μmol g−1 h−1, which outperform all known polyoxometalate (POM)-based metal–organic photocatalysts.

Highly efficient catalysts with enough selectivity and stability are essential for electrochemical nitrogen reduction reaction (e-NRR) that has been considered as a green and sustainable route for synthesis of NH

As a critical air dissolving system, the performance of air flotation equipment directly determines the adhesion efficiency and pollutant removal efficiency of air flotation processes. The factors affecting the performance of air flotation equipment and the relationships between equipment performance and pollution removal efficiency were studied. The results show that when the dissolved gas pressure was 0.4 MPa and the air intake rate was 24 mL/min, the dissolved gas efficiency of the equipment reached its highest value of 55%, the average particle size of bubbles was maintained at 24 µm, and the dissolved oxygen (DO) content significantly increased. When the dissolved gas pressure was 0.4 MPa, the air intake rate was 24 mL/min, and the coagulant dose was 6 mg/L; the removal rates for turbidity, chlorophyll-a, total organic carbon (TOC), and UV absorbance at 254 nm (UV

Electrochemical nitrogen reduction reaction (NRR) has been identified as a prospective alternative for sustainable ammonia production. Developing cost-effective and highly efficient electrocatalysts is critical for NRR under ambient conditions. Herein, the hierarchical cobalt-molybdenum bimetallic sulfide (CoS

To investigate the relationship between the structures of polyoxometalate host–guest materials and their energy-storage performance, three novel polyoxometalate-based metal–organic compounds, [Ag10...

Polyoxometalate-based metal-organic frameworks (POMOFs) possess promising applications as capacitors. Herein, we report the syntheses, structures and electrochemical properties of five copper-containing POMOFs: [CuI4H2(btx)5(PW12O40)2]·2H2O (1), [CuIICuI3(H2O)2(btx)5(PWVI10WV2O40)]·2H2O (2), [CuI6(btx)6(PWVI9WV3O40)]·2H2O (3), [CuI4H2(btx)5(PMo12O40)2]·2H2O (4) and [CuIICuI3(btx)5(SiMoVI11MoVO40)]·4H2O (5) (btx = 1,4-bis(triazol-1-ylmethyl) benzene) with potential applications as capacitors. Compounds 1–3 contain the same Keggin-type polyoxometalate (POM) although with different oxidation states, allowing the analysis of the effect of the electronic population on the capacitance performance of this Keggin-type POM. Compounds 1/4 and 2/5 present the same microstructure but different chemical composition, allowing the analysis of the effect of the chemical composition on the capacitance performance of these isostructure POMOFs. Compound 4 shows the highest specific capacitance (237.0 F g−1 at 2 A g−1) with capacitance retention of about 92.5% after 1000 cycles at a high charge/discharge current density of 10 A g−1. Such superior performance is comparable with state-of-the-art MOF-based and POM-based supercapacitor electrode materials. More important, this work demonstrates that the design and syntheses of POMOFs by tuning single active site (SAS) could guide the development of the new generation of electrode materials for electrochemical capacitors in the near future.

Composites of polyoxometalate (POM)/metallacalixarene/graphene-based electrode materials not only integrate the superiority of the individual components perfectly but also ameliorate the demerits to some extent, providing a promising route to approach high-performance supercapacitors. Herein, first, we report the preparations, structures, and electrochemical performance of two fascinating POM-incorporated metallacalixarene compounds [Ag

Heteropolyacids (PMo6W6) and ferrocene (Fc) were assembled on the glassy carbon electrode for the first time by electrodepositon method, and further combined with reduced graphene oxide (RGO) through the layer-by-layer self-assembly technology, developing a novel non-enzymatic nanocomposite for xanthine (XA) detection. The detection signal of XA was greatly amplified on the Fc-PMo6W6/RGO nanocomposite modified electrode due to coexist of these three active components. As ferrocene and PMo6W6 all have relatively good electrochemical reversibility, fast electron transfer ability and generation of stable redox forms, meanwhile RGO can enlarge the active surface area of the electrode, increase the conductivity and load of ferrocene and PMo6W6. Under the optimized conditions, the developed nanocomposite modified electrode displayed superb sensing property towards xanthine with a widely linear range from 5.00 × 10−8 ∼ 2.03 × 10-3 M, along with a relatively low detection limit of 1.01 × 10-8 M. The modified electrode has good stability as it is prepared by the smart combination electrodeposition and layer-by-layer self-assembly. Additionally, the nanocomposite was applied in detecting xanthine in actual samples with acceptable results, demonstrating the feasibility of Fc-PMo6W6/RGO nanocomposite in routine testing xanthine to some extent.

A sensitive non-enzymatic electrocatalyst based on a nanocomposite of Prussian blue nanocubes (PB NCs) coated with vanadium-substituted polyoxometalates (POMs) was reported in this work. The PB NC@POM nanocomposite was directly constructed using a self-assembly approach with the aid of poly(ethylenimine) (PEI), showing excellent electrocatalytic capacity toward ascorbic acid (AA) oxidation because of the synergistic effect of PB NCs and POMs. Additionally, the negatively charged POM anions can also serve as binding sites with high affinity to the open metal centers of PB NCs, reducing the diffusion of PB NCs out of the nanocomposite and improving the overall stability. The resulting PB NC@POM-based sensor exhibited outstanding sensing capability for AA, including a wide linear range of 7.50 × 10−7 to 4.10 × 10−4 M, and a low detection limit of 5.14 × 10−7 M (at S/N = 3), as well as good anti-interference and stability. Moreover, such excellent recoveries were obtained from the real sample experiments (in drinks/human urine), demonstrating that the PB NC@POM-based sensor was an excellent potential platform for the detection of ascorbic acid in practical applications.

A new polyoxometalate (POM)-based inorganic-organic compound [Cu2(bimb)2(ox)](W6O19)·4H2O [bimb = 1,3-bis(1-imidazoly)benzene, ox = oxalic acid] (1), has been synthesized by hydrothermal reaction, and characterized by IR spectroscopy, single crystal X-ray diffraction, and powder X-ray diffraction. It consists by porous metal-organic 2D positive layers [Cu2(bimb)2(ox)]n2n+ and the W6O192− clusters serving as anionic pillars that make [Cu2(bimb)2(ox)]n2n+ positive layers aggregating around W6O192− clusters to achieve a novel porous intercalation structure. The compound 1 show high electrocatalytic activity for hydrogen evolution reaction (HER) with low overpotential (η) of 146 mV at a current density of 10 mA·cm−2, which is superior than the most of reported POM-based electrocatalysts. This is probable due to its unique porous intercalation structure that H+ can diffuse easily through the pores. Also, the HER mechanism was discussed, and the electrocatalytic reduction of NO2− ions was studied.

Rational fabrication of carbon-based materials hybridized with transition-metal oxides is crucial for the design of supercapacitor electrodes with superior properties. Herein, a sequential anionic polymerization, chemical bath deposition and annealing process are reported to synthesize double-shell hollow NiO@N-C nanotubes using PPy as the nitrogen-doped carbon precursor and MoO3 as the sacrificial template. The introduction of heteroatoms into carbon materials can significantly enhance the conductivity of these materials for their application in the energy storage field. Furthermore, the controlled hollow tubular structure provides extra space to efficiently shorten the ion transfer path and alleviates the effects of volume contraction and expansion. As a result, the NiO@N-C composite exhibits the decent specific capacitance of 782 F g−1 at the current density of 0.5 A g−1 and the impressive capacitance retention of 89.8% over 2000 cycles; remarkably, the double-shell hollow structure synthesized herein has potential applications in high-performance supercapacitors.

Metal organic frameworks hold great potential for high-performance supercapacitors owning to ultrahigh specific surface area and exceptional porosity. Nevertheless, the poor charge transfer kinetics and chemical instability in alkali medium still remain a significant challenge. Herein, a facile dissolved and reassembled strategy towards sandwich-like rGO@NiCoAl-LDHs is proposed to address these drawbacks. NiAl-LDHs can be used as an accumulator to accommodate and reassemble the cobalt ions dissolved from ZIF-67. Graphene could facilitate charge transfer and provide more active sites. Meanwhile, the sandwich-like structure could shorten the transfer distance of electrons and reduce the diffusion resistance of electrolyte. The electrochemical performance is drastically improved due to the enhancement of intrinsic activity reassembling from sandwich-like rGO@ZIF-67@NiAl-LDHs to rGO@NiCoAl-LDHs during cycle process. The electrode material delivers a superior specific capacity of 2291.6 F/g at 1 A/g in a three-electrode configuration. The assembled rGO@NiCoAl-LDHs//AC fulfills a high energy density of 91.4 Wh/kg at a power density of 875 W/kg. In a word, this dissolved and reassembled strategy could possess the huge prospect for energy-related devices.

Constructing a specific nanocomposite film with a large surface area and excellent electrocatalytic activity is important for its application as an electrochemical sensor. In this study, for the first time, an ultrahigh performance composite film based on a heteropolyanion PW9V3O403− (abbreviated as WV) decorated by Pt@Pd alloy nanoparticles (Pt@Pd NPs) and Prussian blue nanoparticles (PB NPs) was illustrated via a layer-by-layer self-assembly approach. The composition, morphologies, and nanostructures characteristics of the [PB/WV–Pt@Pd]6 composite film were completely studied by scanning electron microscopy (SEM), atomic force microscopy (AFM), UV-vis spectroscopy, FT-IR spectra, and X-ray photoelectron spectroscopy (XPS), respectively. The special irregular morphology of the [PB/WV–Pt@Pd]6 composite film provides a high specific surface area to boost the electrochemical activity, while the larger roughness and strong electronic cloud facilitate H2O2's fast reduction at pretty low potential. Under optimum conditions, the [PB/WV–Pt@Pd]6 composite film-based sensor presented a broad linear scope of 4.00 × 10−7 M to 2.65 × 10−3 M and a low detection limit of 1.00 × 10−7 M (S/N = 3). Thus, with seeming stability, anti-interference performance, and selectivity, the suggested sensor could be conceivably utilized to detect H2O2 in actual samples.

In this account, a well-aligned hierarchical nickel sulfide@reduced graphene oxide@nickel aluminum layered double hydroxides composite (denoted as Ni3S2@rGO@NiAl-LDHs) supported on a Ni-foam substr...