Synthesis of eosin modified TiO2 film with co-exposed {001} and {101} facets for photocatalytic degradation of para-aminobenzoic acid and solar H2 production

Abstract Owing to the increasing photosensitivity and DNA damage properties of para-aminobenzoic acid (PABA), concerns have been raised over the exposure of humans to PABA. Solar light-driven photocatalysis (SPC) provides a promising solution for the effective removal of organic pollutants especially when directed towards sulfate radical (SO4 −) production. Herein, we have developed a sulfite-enhanced SPC using Eosin-Y sensitized TiO2/Ti film as a photocatalyst. The removal efficiency of PABA was enhanced by coupling Eosin-Y with TiO2/Ti film as revealed from 23.6 and 48.9 % PABA degradation by reference-TiO2/solar and Eosin-TiO2/solar, respectively. The apparent rate constant of PABA degradation by Eosin-TiO2 was improved by 4.7 times in presence of 5 mM sulfite. Interestingly, Eosin-TiO2 showed appreciable H2 production rate under visible light illumination. Solar/sulfite/Eosin-TiO2 system is a promising technology for environmental sustainability by using the renewable solar energy and air pollutants since sulfite is a waste from flue gas desulfurization process.