High Supercapacitor Electrode Performance of Cu2ZnSnS4 (CZTS) Thin Films Grown by ECD

Abstract

In this paper, we studied the capacitive performance of kesterite Cu2ZnSnS4 (CZTS) electrode growth by electrochemical deposition technique (ECD) on an ITO (Indium tin oxide) substrate at room temperature for the first time. They were then annealed at 580 °C for an hour in a N2 atmosphere with sulfur powder. The X-ray diffraction (XRD) peaks of the CZTS sample revealed to the tetragonal crystal structure, characteristic peaks (2 2 0) and (1 1 2) corresponding to the kesterite phase. The Raman spectrum of the CZTS thin films (TFs) displayed a prominent peak at around 324 cm⁻¹. The surface morphology typically demonstrated that the growth was spread across the entire surface, with each region displaying similar, yet heterogeneous structures at varying depths. From cyclic voltammetry (CV), at a scan rate of 1 mV/s, the specific capacitance (SC) value was determined as 1483 F/g, while it was calculated as 73 F/g for 100 mV/s scanning rate. Also, from galvanostatic charge-discharge measurement, the SC value of CZTS TF electrode was determined to be 1695 F/g at a current density of 1 A/g, while this value was 277 F/g at at a current density of 10 A/g. It has been discovered that CZTS TFs produced electrochemically exhibit excellent supercapacitive performance.