Bimetallic-MOF Derived Accordion-like Ternary Composite for High-Performance Supercapacitors

Abstract

Supercapacitors are regarded to be highly probable candidates for next-generation energy storage devices. Herein, a bimetallic Co/Ni MOF is used as a sacrificial template through an alkaline hydrolysis and selective oxidation process to prepare an accordion-like ternary NiCo2O4/β-NixCo1–x(OH)2/α-NixCo1–x(OH)2 composite, which is composed of Co/Ni(OH)2 nanosheets with large specific surface as the frame and NiCo2O4 nanoparticles with high conductivity as the insertion, for supercapacitor application. This material exhibits both high specific capacitance (1315 F·g–1 at 5 A·g–1) and excellent cycle performance (retained 90.7% after 10 000 cycles). This hydrolysis–oxidation process, alkali hydrolysis followed by oxidation with H2O2, offers a novel approach to fabricate the Ni/Co-based electrode materials with enhanced supercapacitor performance.