Boosting carrier utilization in Pr3+-doped long-afterglow photocatalysts through oxygen vacancy engineering for enhanced photo-Fenton degradation

Long-afterglow photocatalytic technology offers promising potential for all-weather pollutant treatment, yet its efficiency is often constrained by competition between afterglow emission and photocatalytic reactions. To address this, we developed a Pr 3+ -doped Ca 2 Al 2 SiO 7 (CASO) photocatalyst enriched with oxygen vacancies (V O ). The introduction of oxygen vacancies significantly increases trap concentration, enhancing both the intensity and duration of the afterglow emission. A persulfate-assisted photo-Fenton system was designed based on V O -CASO: Pr 3+ enabling the self-activated degradation of tetracycline hydrochloride (TC) under ultraviolet afterglow. The photo-Fenton reaction consumes excess holes accumulated during the afterglow process, improving carrier utilization efficiency and mitigating rapid recombination. Additionally, persulfate addition can enrich reactive species and facilitate the Fe 2+ /Fe 3+ cycle. Benefiting from these synergistic effects, V O -CASO: Pr 3+ has achieved 75% TC degradation within 1 h, significantly outperforming traditional systems. This study provides a new strategy for enhancing long-afterglow photocatalytic performance, paving the way for sustainable pollutant degradation technologies.