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To further improve the electrochemical performance of supercapacitor, the construction of composite based electrode material was proved to be an effective strategy. Herein, CoS-decorated Ni-MOF composites with hierarchical structures and obvious synergistic effects were synthesized by one-step hydrothermal and subsequent electrodeposition route. Benefitting from the increased surface roughness with more exposed active sites, the hierarchical structure with high space utilization rate for rapid ion transport as well as the improved conductivity and entire robustness, the optimal composites exhibited an excellent specific capacitance (2167.5 F g−1 at 1 A g−1), outstanding rate performance (up to 70.1% even at 5 A g−1) and the good cycle stability (80.12% capacity retention after 3500 cycles). The corresponding assembled asymmetric supercapacitors could reach an energy density 92.18 Wh kg−1 when the power density of was 1626.71 W kg−1, which overwhelmed most other reported works. What is more, the capacity retention could maintain 73.34% even after 7000 cycles, indicating the excellent cycle stability. Overall, to our knowledge, this is the first report on a synergistic effect of a combination of Ni-MOF and CoS. The constructed composites exhibited great potential as promising candidates for high-performance energy storage devices. [Display omitted] • The Ni-MOF@CoS composite was prepared via hydrothermal and subsequent electrodeposition route. • The prepared composites provided more exposed active sites, rapid ion transport as well as the improved conductivity and stability. • The synergistic effect between Ni-MOF and CoS was demonstrated. • The obtained electrode exhibited an excellent specific capacitance, rate performance and the stability. • The corresponding asymmetric supercapacitor overwhelmed most other reported works. [ABSTRACT FROM AUTHOR]

Direct ethanol fuel cells (DEFCs), with their boosted energy density and efficiency, are poised to supplant secondary batteries in the near future. However, the pricy and low-durability of Pt-based anode catalyst used in these cells have hampered the development of this technology. We successfully created a Ni-MOF @ nickel foam (NF) to operate as an anode for a DEFC. We next enhanced the electrical conductivity of these produced electrodes with graphene and tested them towards ethanol oxidation in a basic solution. The study looked at the electrodes' surface shape, crystalline structure, chemical and electrical properities, among other things. Furthermore, the electrochemical activity and durability of the prepared electrodes were examined. These tests demonstrated the successful formation of the MOF @ the surface of the NF, with and without reduced graphene oxide. The produced materials outperformed plain Ni foam in terms of ethanol oxidation activity, and the graphene doping significantly enhanced this activity. A 0.35 V onset potential was obtained, with current output increasing concurrently with ethanol oxidation up to 0.5 M before stabilizing. The superior activity was attributed to the prepared electrodes' perfect nano-sheet structure, high porosity, and outstanding mass and charge transport characteristics. The addition of reduced graphene oxide enhanced charge transfer and thus improved the overall performance. [Display omitted] • Ni-MOF @ nickel foam with and without reduced graphene oxide was successfully prepared. • The activity of the prepared electrodes towards ethanol oxidation was investigated. • Results discussed based on charge and mass transfer properties of the prepared materials. [ABSTRACT FROM AUTHOR]

Accurate and rapid determination of blood glucose levels is essential for real-time monitoring and management of diabetes mellitus, and nanomaterials-based nonenzymatic glucose sensing plays an increasingly significant role in this regard. Here, a simple two-step electrodeposition technique that was efficient, environmentally friendly, easily manipulated, and exceedingly controllable was adopted for the synthesis of metal-organic framework (MOF)/carbon material composites on a titanium mesh (TM), namely α-cyclodextrin functionalized reduced graphene oxide/nickel-based MOF (α-CD-rGO/Ni-MOF/TM), in which Ni-MOF served as the electrocatalyst for glucose oxidation, and rGO greatly enhanced the electrochemical performance of Ni-MOF, benefiting from α-CD effectively preventing aggregation of rGO nanosheets while also improving the stability of the composites, so that these endow the obtained nanomaterials exhibited remarkable electrocatalytic ability for glucose. Consequently, the as-prepared glucose sensor revealed two linear dynamic ranges of 0.65 μM− 4.828 mM with a sensitivity of 1395 μA mM−1 cm−2 and 4.828 − 9.178 mM with a sensitivity of 760 μA mM−1 cm−2 together with a rapid response time of only 1.9 s and a low detection limit of 0.3 μM as well as distinguished reproducibility, selectivity, and stability, further demonstrating the synergistic effects of this composite. The newly manufactured glucose sensing platform was also successfully used to detect glucose in real serum. Considering the convenience and controllability of two-step electrodeposition, the α-CD-rGO/Ni-MOF/TM composite holds great promise for commercial potential, and also provides direction and technical reference for the synthesis of MOF/carbon material composites. [Display omitted] • α-CD-rGO/Ni-MOF was firstly prepared with two-step electrodeposition method and used as electrode material for glucose sensor. • The sensor exhibited wide linear range and low detection limit under optimized conditions. • The synergistic effect of composite electrocatalyst in detection of glucose was confirmed. • This simple and controllable strategy provides some guidance for the preparation of other MOF/carbon material composites. [ABSTRACT FROM AUTHOR]

• Ni-MOF on MXene is vulcanized to sandwiched p-MXene/Ni 3 S 4 /CuS in the presence of copper. • p-MXene/Ni 3 S 4 /CuS show the remarkable specific capacitance. • The p-MXene/Ni 3 S 4 /CuS//AC has a high energy density and ultrahigh cyclic stability. [Display omitted] Metal-organic frameworks (MOFs) have ordered porous structure and intriguing properties for supercapacitors, however, poor conductivity and cycle stability limits their application. To solve these problems, hence, a simple strategy is proposed, by which MOFs are in-situ grown in the porous conductive p-MXene substrate. And then, along with the introduction of CuS, the grown Ni-MOF is derived to Ni 3 S 4 , which is more stable and more electrochemically active. Due to higher contact area, excellent synergistic effect and more exposed active sites, the prepared sandwiched p-MXene@Ni 3 S 4 /CuS nanostructure displays a big specific capacitance (1917 F·g−1) and superior cycling performance (91.2%@30000). What's more, the assembled p-MXene@Ni 3 S 4 /CuS//AC asymmetric device delivers a high energy density of 87.62 Wh·Kg−1 at the power density of 775.02 W·Kg−1, suggesting that this material provides a brilliant candidate for energy storage. [ABSTRACT FROM AUTHOR]