Oxygen vacancies and Y-O-Ag bonds in the Z-scheme heterojunction cooperate to promote photodegradation of organic pollutants

Y 2 O 3 is a cost-effective and environmentally friendly wide-band gap photocatalyst with extensive application potential. However, its limited ability to be excited by visible light restricts its practical uses. In this study, we coupled the narrow bandgap semiconductor AgI with Y 2 O 3 to form a Z-scheme heterostructure , significantly promoting its photocatalytic degradation activity. Characterization and experimental results demonstrated the formation of Y-O-Ag bonds through coupling with AgI, leading to an increase in oxygen vacancies in Y 2 O 3 , which promotes the chemisorption of H 2 O and O 2 . The Y-O-Ag bond introduction promotes electron transfer , improves hole utilization, and boosts energy transfer efficiency, thus promoting the efficient generation of ·OH and 1 O 2 . The photocatalytic degradation rates of RhB and o-nitrophenol by 7.5% AgI/Y 2 O 3 were 26.5 and 4 times higher than those of pure Y 2 O 3 , respectively. This study provides theoretical support for the Z-scheme heterojunction to improve photocatalytic activity and offers efficient solutions and practical design ideas for sewage purification.