Thermal Stability on Solid State Symmetric Supercapacitors with Hydrothermally Synthesized Cu2CoSnS4 Electrodes

The effects of thiourea concentration on crystal phase, morphology, and the elemental composition and electrochemical characteristics (ECs) of hydrothermally synthesized Cu2CoSnS4 (CCTS) electrodes are systematically studied. In a three-terminal (3T) configuration, layered structure morphology with Cu-rich chemical composition-based electrodes exhibits higher ECs than other electrodes. The thermal reliability of devices up to 60 degrees C is practically validated via temperature-dependent cyclic voltammetry (CV) and galvanostatic chargedischarge (GCD) measurements for single symmetric solid-state supercapacitor (SSC) devices. The maximum of C-p=(251.87 +/- 30.56)Fg(-1), E=(89.55 +/- 10.35)Whkg(-1), P=(800 +/- 40.32)Wkg(-1) and voltage window expanded up to 1.6 V including red LED operation for 6 min are achieved for the serially connected two SSCs at 1Ag(-1), indicating that CCTS can be one promising electrode material for SSCs.