Construction of defect-heterojunction based on B-phase TiO2 to facilitate carrier delay relaxation

The efficient photocatalytic eliminate of persistent pollutants is crucial for advancing photocatalytic technology in environment applications. Constructing efficient heterojunction photocatalysts represents a key strategy for prolonging the lifetime of photo generated charge carriers and enhancing photocatalytic performance. In this study, an In 2 S 3 /TiO 2 -2:1 defect-heterojunction photocatalyst was developed, which exhibited exceptional degradation ability for recalcitrant contaminants including trenbolone acetate (TBA), acetaminophen, and phenol. Remarkably, over 99 % of TBA was degraded in 30 min, with comprehensive environmental risk assessment confirming minimal ecological impact from degradation intermediates. Transient fluorescence spectroscopy and transient surface photovoltage spectroscopy were performed to evaluate the relaxation process of photogenerated carriers. The results showed that the carrier relaxation time of In 2 S 3 /TiO 2 -2:1 defect-heterojunction photocatalyst was significantly prolonged, which effectively promoted the photocatalytic activity. This study provides valuable references for the design and development of high-performance defect-heterojunction photocatalysts.