Three-Dimensional Tree-Like (Ni,Co)Se 2 /Ni(Oh) 2 Hybrid Electrode For Flexible Supercapacitors

The rational design of hierarchical nanostructure consisting of multiple components with remarkable electrochemical performance is regarded as a significant technique for fabricating high-performance energy storage devices. Herein, self-supported tree-like (Ni,Co)Se 2 /Ni(OH) 2 heterogeneous nanoarrays on carbon cloth (CC) used as electrode materials of supercapacitors (SCs) are designed and synthesized by a multi-step approach. The (Ni,Co)Se 2 core can boost electron transport due to excellent conductivity, and the shell layer of Ni(OH) 2 nanoflakes improves the surface area. Profiting from the cooperative effects of two active materials and core-shell architecture, the tree-like (Ni,Co)Se 2 /Ni(OH) 2 composite delivers a superior capacity, outstanding rate capability and still retain 151.3 mAh g -1 after 3000 charge/discharge cycles. Meanwhile, the flexible hybrid supercapacitor (HSC) fabricated by the (Ni,Co)Se 2 /Ni(OH) 2 and activated carbon (AC) also manifests a satisfied specific energy of 0.79 mWh cm -2 under 1.35 mW cm -2 . Therefore, it can be considered that the as-prepared hierarchical (Ni,Co)Se 2 /Ni(OH) 2 nanoarrays are promising candidate for HSC devices in energy storage and conversion