Hybridizing ZnCo2O4-decorated MWCNTs: Electrode to symmetric solid-state supercapacitor configuration

Abstract

Meticulously crafted architectures of hybrid materials through logical and rational design play an essential role in amplifying the performance of supercapacitors. Herein, high-density sequential growth controlled ZnCo₂O₄ nanoparticles decorated on ‘dip and dry’ coated MWCNTs is proposed as a hybrid supercapacitive electrode to design a solid-state configured symmetric supercapacitor (SSS) device. Synthesized MWCNT/ZnCo₂O₄ has been utilized as an electrode at a scan rate of 5 mV s⁻¹ and a specific capacitance of 1081 F g⁻¹ is attained with 72% capacitive retention after 10,000 CV cycles. Furthermore, the MWCNTs/ZnCo₂O₄ device showcased a volumetric capacitance of 157 mF cm⁻³, a volumetric energy density of 21.80 mW h cm⁻³, and a balancing volumetric power density of 1509.79 mW cm⁻³ at a current density of 0.92 mA cm⁻³.