0D/1D CuWO4/Mn0.3Cd0.7S S-scheme heterojunctions for full-spectrum bifunctional photocatalytic degradation and hydrogen production

Integrating photocatalytic oxidation for pollutant removal with hydrogen production via photocatalysis presents a promising approach for sustainable water purification and renewable energy generation, circumventing the sluggish multi-electron transfer inherent in photocatalytic water oxidation. This study introduces novel zero-/one-dimensional (0D/1D) CuWO4/Mn0.3Cd0.7S step-scheme (S-scheme) heterojunctions that exhibit exceptional bifunctional capabilities in photocatalytic degradation and hydrogen production under full-spectrum illumination. The degradation efficiency for tetracycline (TC) using 5 %-CuWO4/Mn0.3Cd0.7S reaches 94.3 % and 94.5 % within 60 min and 6 h, respectively, under ultraviolet–visible (UV–Vis) and near-infrared (NIR) light. Notably, these 0D/1D CuWO4/Mn0.3Cd0.7S S-scheme heterojunctions demonstrate superior hydrogen production, achieving rates of 12442.03 μL g-1h−1 and 2418.54 μL g-1h−1 under UV–Vis light and NIR light irradiation, respectively—these rates are 2.3 times and 55.2 times higher than that of Mn0.3Cd0.7S alone. This performance enhancement is attributed to the intrinsic dimensional effects, transitions of transition metal d-d orbitals, and S-scheme hole/electron (h+/e−) separation characteristics. Additionally, experimental results and density functional theory (DFT) calculations have clarified the modulation of electronic configurations, band alignment, and interfacial interactions via 0D/1D S-scheme heterojunction engineering. This study sheds light on the electron transfer mechanism within S-scheme heterojunction and enhances the effectiveness, economy, and sustainability of recalcitrant pollutant removal and hydrogen production.