Rational designing NiVO3@CoNi-MOF heterostructures on activated carbon cloth for high-performance asymmetric supercapacitors and oxygen evolution reaction

The NiVO3@CoNi-MOF/AC with enhanced kinetics and optimized charge storage behavior demonstrate excellent electrochemical performance. The asymmetric supercapacitor assembled by the NiVO3@CoNi-MOF/AC and AAC presents outstanding energy storage performance and is superior to many currently reported similar devices. [Display omitted] •By an ingenious morphology control strategy, the NiVO3@CoNi-MOF heterostructures are successfully anchored on the carbon cloth.•The NiVO3 coating effectively boosts the kinetics of CoNi-MOF, optimizing the charge storage behavior and achieving efficient oxygen evolution reaction.•The NiVO3@CoNi-MOF//AAC asymmetric supercapacitors exhibit excellent rate capability, cycle stability and energy storage performance. Binder-free self-supported carbon cloth electrode provides novel strategies for the preparation of MOFs, effectively improving the conductivity and promoting charge transfer. Combining MOFs with vanadate to form a unique heterogeneous structure provides a large specific surface area and more active sites, further enhancing the kinetics of MOFs. Herein, a self-supported carbon cloth electrode is prepared by in-situ growth of CoNi-MOFs on activated carbon cloth (AC) and coating with NiVO3. The heterostructure increases the specific surface area and exposes more active sites to promote the adsorption and diffusion of ions, thus enhancing the kinetic activity and optimizing charge storage behavior. As expected, the NiVO3@CoNi-MOF/AC exhibits a specific capacitance of up to 19.20 F/cm2 at 1 mA/cm2. The asymmetric supercapacitors (ASCs) assembled by NiVO3@CoNi-MOF/AC and annealed activated carbon cloth achieve an energy density of 1.27 mWh/cm2 at a power density of 4 mW/cm2 and have a capacitance retention of 96.43 % after 10,000 cycles. In addition, the NiVO3@CoNi-MOF/AC as electrocatalyst has an overpotential of 370 mV at 10 mA/cm2 and a Tafel slope of 208 mV dec-1, demonstrating remarkable electrocatalytic oxygen evolution reaction performance. These unique heterostructures endow the electrode with more electrochemical selectivity and provide new key insights for designing multifunctional materials.