An in-depth study of integrating cascaded photocatalytic HO generation and activation with solar-driven interfacial evaporation for in-situ organic contaminant remediation.

Integrating cascaded photocatalytic HO generation and subsequent activation of HO (into ·OH radicals) with solar-driven interfacial evaporation techniques offers an effective and sustainable approach for in-situ treating water contaminated with organic substances. Unlike traditional water-dispersed catalysts, the interfacial evaporation approach presents unique challenges in photocatalytic reactions. We explored these dynamics using an AgI/PPy/MF interfacial photothermal set, achieving HO production efficiency (approximately 1.53 mM/g/h) - three times higher than submerged counterparts. This efficiency is attributed to exceptional solar light absorption (about 95 %), a significant surface photothermal effect (raising temperatures by approximately 36 °C), and enhanced oxygen availability (38 times more than in water), all characteristic of the interfacial system. The in-situ activation of HO into ·OH notably improves the degradation of organic pollutants, achieving up to 99 % removal efficiency. This comprehensive analysis highlights the potential of combining photocatalytic HO processes with interfacial evaporation for efficiently purifying organically polluted water.