Improved All‐solid‐state Z‐scheme Photocatalytic System Based on TiO 2 /Ag−Pd/CdZnS

Abstract We present an innovative Z‐scheme photocatalytic system, TiO 2 /Ag−Pd/Cd 0.8 Zn 0.2 S, exhibiting remarkable stability in aqueous solutions containing benzyl alcohol/acetic acid. Its performance rivals that of the benchmark Z‐scheme catalyst, ZnO/Pt/Cd 0.8 Zn 0.2 S. Thorough characterizations were performed using XRD, XPS, TEM, and UV‐Vis techniques, examining both the entire Z‐scheme system and its individual components, namely Ag−Pd/TiO 2 and Cd 0.8 Zn 0.2 S. The standout performer, TiO 2 /Ag−Pd/Cd 0.8 Zn 0.2 S, demonstrated an apparent quantum yield (AQE) of 7 % within the 350–650 nm range. In contrast, AQEs for Ag−Pd/TiO 2 and Cd 0.8 Zn 0.2 S were 0.6 % and 2.1 %, respectively, under identical conditions. Furthermore, we propose a charge transfer mechanism supported by femtosecond transient absorption spectroscopy (FTAS). This investigation not only introduces a stable Z‐scheme system with superior photocatalytic hydrogen production capabilities but also advances the FTAS technique for mechanistic exploration. In essence, our research paves the way for more efficient metal oxide/metal/Cd(Zn)S hybrid systems in the realm of photocatalysis.