Maximizing solar potential: Designing an innovative S-scheme Ti₃C₂T_x/α-Fe₂O₃/CdS Mott Schottky heterojunction with unparalleled photocatalytic H₂ evolution induced by visible light

The current study involved the construction of novel, cost-effective, and efficient heterojunctions using Ti₃C₂Tx as a co-catalyst by fabricating a binary heterojunction based on α-Fe₂O₃ and CdS for photocatalytic H₂ production by water splitting. A unique and strong interface formed between the functional group on the surface of the metallic co-catalyst and CdS aided in the boosted hydrogen production. The Mott Schottky barrier established between Ti₃C₂Tx and CdS nanosheets (NSs) enhanced the electron-holes separation thus preventing the electrons from recombining and lowering the chance of any loss during the photocatalytic reaction by ensuring an enriched supply of electrons over the wide surface area having an abundance of activity for the light capture all leading to the exceptional H₂ production. This fabricated Ti₃C₂T_x/α-Fe₂O₃/CdS step-scheme (S-scheme) hybrid heterojunction exhibited remarkable stability for 176 hours without degradation, underscoring its capacity for reusing and repeated utilization. The complex electronic and structural properties of heterojunction ternary composite were studied by using different techniques including XRD, SEM, TEM, and PL spectroscopy. The XPS and UV–visible spectroscopy studies confirmed that the synthesized heterojunction via the hydrothermal method had significantly increased photocatalytic H₂ evolution reaction (HER) rate and stability. The maximum HER activity measured in the optimized ternary composite was recorded to be 66.04 mmol/gh at 420 nm with a very high apparent quantum yield (AQY) of 74.78 % at 420 nm.