Ni2P/ZnP2 nanocrystals/rGO decorated on NiO/ZnO nanoflakes as a high-performance cathode for flexible hybrid supercapacitor

Development of high-performance hybrid supercapacitors (HSCs) requires an excellent battery-type electrode material with highly active and stable nanostructures. In this report, we present a novel battery-type electrode material for HSCs which is built upon Ni2P/ZnP2 nanocrystals/ reduced graphene oxide (rGO) decorated on three-dimensional (3D) NiO/ZnO nanoflakes (NFs) by utilizing carbon cloth (CC) as current collector. This strategy is aimed to achieve a stable architecture, enhanced conductivity and accessibility of redox active sites, all of these can facilitate the transportation of ion/electron for faradaic reactions. Employing NiO/ZnO@Ni2P/ZnP2/rGO as the cathode which presents a remarkable mass specific capacity of 838.5 C g−1 and an outstanding cyclic lifespan (97.3 % charge retentions subsequent to 4000 cycles). In addition, a flexible HSC equipped with activated carbon (AC) as the anode as well represents a satisfactory energy density of 16.43 Wh kg−1 with a power density of 932.74 W kg−1 and an exceptional cycling stability (capacity retention of 91 % after 10,000 cycles).