Overcoming photocorrosion in CdS-based photocatalyst via MoS₂/rGO cocatalyst decoration: A facile strategy for sustainable H₂ production

Providing sustainable and economically feasible cocatalyst to hamper the effect of photocorrosion in CdS-based photocatalyst for hydrogen production is of great important. Herein, a novel and facile synthesis using ultrasonication assisted method was employed to load MoS₂ and rGO nanosheets on CdS NRs without addition of any reducing agent or surfactant. Various characterization techniques, including XRD, FTIR, BET, UV–Vis and FE-SEM, were used to provide information on the structure, chemical composition, morphology and optical properties of the prepared photocatalysts. The photocatalytic activity of the as-synthesized rGO-CdS/MoS₂ composite was investigated under visible light irradiation in the presence of Na₂S/Na₂SO₃ solution as sacrificial agent. The optimized composite (CMS-2G) produced an exceptional amount of hydrogen up to 191.94 mmolg⁻¹h⁻¹ which is 29.9-fold and 4.4-fold more than bare CdS and CMS-10 composite respectively. This improved amount of hydrogen is attributed to the effect of ultrasonically dispersed MoS₂ and rGO on CdS NRs leading to effective heterojunction formation by wrapping MoS₂ on the surface of nanostructured CdS NRs which also reduced the band gap from 2.4 to 2.16 eV. The rGO in the composite serves as electron sink which aided the swift movement of photoexcited electrons to partake quickly in the redox reaction. The photostability of CdS has considerably increased under continues irradiation. Suggestively, this system presents a simple method for the development of a highly efficient, noble-metal free and economical photocatalyst for water splitting to produce hydrogen under solar irradiation.