Surface modification of Ni(OH)2 nanosheets with PEDOT:PSS for supercapacitor and bendable electrochromic applications

Abstract Owing to the chemical resistance, facile production and high electrochemical activity, layered Ni(OH)2 is a useful electrode material for supercapacitors and electrochromic (EC) devices. Nevertheless, the poor electrical conductivity of Ni(OH)2 and its strong tendency to restack during processing have restricted its applications. In this study, we have modified Ni(OH)2 surfaces with a layer of poly(3,4-ethylenedioxythiophene):polystyrenesulfonate (PEDOT:PSS) using (3-glycidyloxypropyl)trimethoxysilane (GOPS) as a linker. A nanospace can be created by the conductive layer of PEDOT:PSS wrapped on the Ni(OH)2 nanosheet, which can avoid the reaggregation. Therefore, the Ni(OH)2/PEDOT (P–Ni(OH)2) composites display greater electrochemical activity and kinetics due to the favorable conductivity and interfacial area, suitable for supercapacitor and EC applications. The flexible electrochromic device (ECD) and an asymmetric supercapacitor (AS) incorporating P–Ni(OH)2 are also evaluated in this article. The P–Ni(OH)2 based ECD exhibits superior mechanical stability and the AS also shows excellent cycling stability.