Asymmetric Ce-O-Zn interface in silver-decorated CeZnO/ZnO solid solution-oxide heterojunction for enhanced photocatalytic degradation performance

The rational design of solid-solution-oxide heterostructure presents a promising pathway to synergize band structure engineering and interfacial charge dynamics in advanced photocatalysis. Herein, a novel S-scheme CeZnO/ZnO heterojunction was fabricated through solid-solution lattice engineering, where Ce-O-Zn covalent bonding networks are strategically constructed at phase boundaries via controlled exceedance of the Ce solubility limit in ZnO matrix. Coupled with Ag nanoparticle-induced localized surface plasmon resonance (LSPR), this hierarchical system achieves remarkable visible-light-driven tetracycline (TC) degradation (90.4 % within 60 min). The outstanding degradation performance can be attributed to the formation of a built-in electric field at the Ce-O-Zn interface, the presence of oxygen vacancies, and the synergistic catalytic effect of Ag nanoparticles. Density functional theory (DFT) calculations and experimental characterizations further reveal that the CeZnO/ZnO heterojunction facilitates S-scheme charge transfer via Ce-O-Zn bonds, improving charge transfer and separation efficiency while preserving the strong redox capability of photo-generated charge carriers. This study provides valuable insights into the design of high-performance heterojunction photocatalysts and carries significant implications for the development of photocatalysis.