RGO-MoS₂ Supported NiCo₂O₄ Catalyst toward Solar Water Splitting and Dye Degradation

Abstract

Formation of the NiCo2O4 (NCO) nanoparticle with the simultaneous reduction of GO and growth of MoS2 by a two step hydrothermal process results in a 2D RGO-MoS2 (R-MoS2) cocatalyst layer with intimate interfacial contact with NCO. The phase purity, chemical coupling and morphology of the synthesized materials are established through X-ray diffraction, Raman and X-ray photoelectron spectroscopy studies. The ternary composite, RGO-MoS2-NiCo2O4 (RM-NCO), shows excellent electrocatalytic performance toward solar driven water splitting with 3.08% solar to hydrogen (STH) conversion efficiency, photocurrent density of 5.36 mA cm–2, injection efficiency of 97% at 1 V (vs Ag/AgCl) and long-term stability. The photo degradation (95%) of Rhodamine B under visible light irradiation is obtained in 90 min by the ternary composite (RM-NCO). The improved performance of the ternary composite, RM-NCO, over bare NCO and MoS2, toward photocatalytic activity is achieved through the dual charge transfer pathway between interfacial layer of NCO and MoS2 to RGO, which leads to generation of more photoinduced charge carriers and suppression of electron–hole recombination process.