Freeze gelation 3D printing of rGO-CuCo2S4 nanocomposite for high-performance supercapacitor electrodes

Reduced graphene oxide (rGO)-CuCo2S4 nanocomposites are synthesized by a facile hydrothermal method. Thiourea has been used as a sulfur source for synthesizing CuCo2S4 nanoparticles. The synthesized materials are then dispersed in phenol with the addition of Polyvinylpyrrolidone (PVP), which acts as a binder to form the homogeneous rGO-CuCo2S4 slurry. This as-prepared slurry is then deposited on the graphite paper using 3D printing technique combined with the freeze gelation method to form a rGO - CuCo2S4 electrode. X-ray diffractometry (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS) and electrochemical techniques have been used to characterize rGO-CuCo2S4 nanocomposite. The nanocomposite has a microporous structure with CuCo2S4 nanoparticles decorated on the rGO sheet surface. Electrochemical studies revealed that the rGO-CuCo2S4 nanocomposite electrode has a high specific capacitance of ca. 1123 F/g at 5 mV/s and excellent capacitance retention. A 91% capacitance remained approximately after 20000 successive cycles at a high current density of 125 A/g are remarkable and it has not been widely reported for a supercapacitor electrode. (C) 2021 Elsevier Ltd. All rights reserved.

Automated summary

Reduced graphene oxide (rGO)-CuCo2S4 nanocomposites were synthesized by a facile hydrothermal method, showing high specific capacitance and excellent capacitance retention in electrochemical studies.