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Binder‐free two‐dimensional mesh‐like structure of nickel‐zinc metal‐organic framework on in‐situ‐coated carbon cloth (Ni−Zn MOF/CC) and Ni−Zn MOF powder were developed via a solvo‐hydrothermal reaction for electrochemical storage application. The electrochemical properties of these electrodes show that the electrodes self‐assembled on carbon cloth substrates exhibit remarkably excellent performance. The Ni−Zn MOF/CC electrode exhibited a capacitance of 653.54 F/g at 1 A/g through a capacity retaining of 87.65% after 10000 cycles. Furthermore, the Ni−Zn MOF//AC coin‐cell asymmetric supercapacitor device (CASD) exhibited remarkable energy and power densities of 54.31 Wh/kg and 825 W/kg, respectively, with adequate capacitance retention up to 94.63% over 5000 cycles at 1.5 V. The CASD also exhibited a significant power density of 4950 W/kg at 19.67 W h/kg, which suggests that these in‐situ developed MOF‐based electrodes may discover application in energy storage devices. [ABSTRACT FROM AUTHOR]

Summary: Metal‐organic frameworks (MOFs) have received considerable devotion as capable electrode materials for energy storage applications. However, applying MOFs to electrodes still faces difficulties including achieving high capacitance, rate performance with good stability. Therefore, in order to further advance the electrochemical activity, it is necessary to rationally design the electrode structure and couple the metallic elements to obtain the desired structure. Here, novel three‐dimensional (3D) hollow microspheres with hierarchical structure of nickel‐zinc MOFs (NZMF) are fabricated in situ on carbon fabric (NZMF/CF) by a solvo‐hydrothermal approach used directly as binder‐free electrode for supercapacitor applications. The rate capacity of NZMF/CF sample is higher than that of NZMF. In addition, the 3D NZMF/CF electrode offered superior specific capacitance (311.11 F g−1) compared with NZMF (273.33 F g−1), ascribed good electrical conductivity of CF scaffold. As a result, a split cell asymmetric supercapacitor device (SC‐ASD) assembled using NZMF/CF//AC/CF attained a good energy density of 22.39 Wh kg−1 at 1650 W kg−1 power density with cyclic stability of 93.69% achieved even after 1000 cycles. This study offers a versatile scheme to efficiently prepare MOF‐based binder‐free energy storage materials for forthcoming hybrid and flexible electronic devices. [ABSTRACT FROM AUTHOR]

The design and fabrication of highly active visible‐light‐driven photocatalysts have been received considerable attention in recent years. However, individual component‐based photocatalysts are limited in their use because of the high recombination of photoinduced carriers and poor chemical stability. Herein, the Z‐scheme‐originated photocatalytic activity of in‐situ deposited Nb2O5 NPs on the plane surface of carbon nitride (g‐C3N4) nanosheets (i. e. CN‐NbO) heterostructures was studied using a simple thermal pyrolysis method. The as‐synthesized photocatalysts distinctly manifested efficient white light‐emitting diode (LED) light irradiation toward organic malachite green (MG) dye degradation and photocatalytic hydrogen generation. The CN‐NbO heterostructure showed a faster degradation rate of the MG dye and a higher photocatalytic hydrogen evolution rate. In addition, the plausible Z‐scheme photocatalytic mechanism for photocatalytic hydrogen production under LED light irradiation was discussed. Photoelectrochemcial studies showed that the superior photoactivity of CN‐NbO heterostructure is mainly a result of the suitable alignment of the band edge positions, which diminish carrier recombination and facilitate efficient interfacial charge transport at their interface. This study provides an ideal method for in‐situ fabrication of novel two dimensional/one dimension‐based photocatalysts with high activity and stable performance for photocatalytic hydrogen generation. [ABSTRACT FROM AUTHOR]