A new strategy for integrating semiconducting SWCNTs into pseudo-cubic In2O3 heterostructures for solid-state symmetric supercapacitors with a superior stability and specific-capacitance

Abstract

Herein, we report a rapid one-step hydrothermal synthesis of semiconducting single-walled carbon nanotubes/pseudo-cubic In₂O₃ heterostructures (s-S/IHs) and successfully demonstrate LED lighting by using symmetric solid-state supercapacitors (SSCs). This is a simple, scalable, proficient and in situ synthesis method to harvest materials that can be engaged as cutting-edge electrode materials for high-energy SSCs. The cost effective and environment-friendly s-S/IH conveys excellent electrochemical properties with a high specific capacitance (641.1 F g⁻¹ at a current density of 1.8 A g⁻¹) and tremendous rate capabilities with an excellent capacitance (335.1 F g⁻¹ at a current density of 3.8 A g⁻¹). The SSC devices with a maximum potential window of 1.2 V are fabricated by using two similar s-S/IH electrodes in order to justify the outstanding performance for real-life energy storage devices. Notably, the SSC devices offered a high specific capacitance (139.5 F g⁻¹ at 2 A g⁻¹), a high energy density (6.9 W h kg⁻¹ at 234.3 W kg⁻¹), an ultra-high power density (789.3 W kg⁻¹ at 4.6 W h kg⁻¹), and a remarkable cycling stability (91.8% specific capacitance retention rate after 5000 cycles). These extraordinary findings illustrate an insight into designing a nanocube In₂O₃ lattice deformed by very small concentration of semiconducting single-walled carbon nanotubes that are economically affordable and environmentally harmonious for the fabrication and demonstration of high performance SSC devices.