LAUSR

The limited reactive active sites on the surface of NiMoO4 electrodes are the main bottleneck, restricting the rate performance of the corresponding supercapacitors (SCs). However, it is still a difficult problem to improve the utilization of redox reaction sites by adjusting the interface of the nickel molybdate (NiMoO4) electrode. This study reports a two-dimensional (2D)/2D core-shell electrode on a carbon cloth (CC) with NiMoO4 nanosheets grown on NiFeZn-LDH nanosheets (NFZ@NMO/CC). The interface of the 2D/2D core-shell structure promotes the redox reaction by improving OH- adsorption and diffusion capacity (diffusion coefficient = 1.47 × 10-7 cm2 s-1) and increasing the electrochemical active surface area (ECSA = 737.5 mF cm-2), which are much larger than the pure NiMoO4 electrode (2.5 × 10-9 cm2 s-1 and 177.5 mF cm-2). The NFZ@NMO/CC electrode exhibits an excellent capacitance of 2864.4 F g-1 at 1 A g-1 and an outstanding rate performance (92%), which is 3.18 times and 1.9 times those of the NiMoO4 nanosheets (33%) and the NiFeZn-LDH nanosheets (57.14%), respectively. Additionally, an asymmetric SC was assembled with NFZ@NMO/CC as the anode and Zn metal-organic framework (MOF)-derived carbon nanosheet (CNS)/CC as the cathode, which exhibited superior energy and power densities (70 Wh kg-1 and 709 W kg-1) with good cycling capability.