Bayberry-like Cu3BiS3 with 2D layered nanosheets of rGO and g-C3N4 for effective electrochemical HER activity

Abstract

Hydrogen production via electrochemical water splitting is still considered as solution for global energy demand. The ternary composite material of copper bismuth sulfide/reduced graphene oxide/graphitic carbon nitride (Cu3BiS3/rGO/g-C3N4) electrocatalyst was produced via hydrothermal for HER activity. The X-ray diffraction study revealed that Cu3BiS3 with carbon composite have orthorhombic phase with an average crystallite size as 43.1 nm. The Raman spectra of Cu3BiS3 with carbon (rGO/g-C3N4) composite revealed the existence of structural defects with ID/IG ratio of 1.01. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) studies was explored bayberry-like Cu3BiS3 nanosphere formation with finely unified rGO and g-C3N4 sheets. In an alkaline medium, the electrocatalytic performance demonstrates the enhancement of the Cu3BiS3 catalyst due to the addition of rGO/g-C3N4 with the low 111 mV overpotential and small 113 mV/dec Tafel slope value. The electrochemical active surface area (ECSA) of Cu3BiS3 with carbon (rGO/g-C3N4) composite was 127.25 cm2, whereas the ECSA values of Cu3BiS3 and Cu3BiS3/rGO were 34.25 and 86.5 cm2, respectively. The results conclude that π-π interaction among rGO and g-C3N4 can effectively improve the conductivity, active sites, surface area and porous nature of the obtained product, which leads to enhance HER performance. Therefore, morphology tuned carbon composite material would be a promising candidate in forthcoming cost-effective and large-scale water splitting applications.