Selective capture of Tl2O from flue gas with formation of p–n junction on V2O5–WO3/TiO2 catalyst under working conditions

Thallium (Tl) compounds, highly toxic to biology, are usually released into flue gas during fossil/minerals combustion, and further distributed in water and soil. In this work, we fundamentally investigated the capture of gaseous Tl2O by industrial V2O5–WO3/TiO2 catalyst under working condition in Tl-containing flue gas. Experimental and theoretical results indicated that the Tl2O has significant electron-feeding capacity and easily donate electron to unoccupied orbitals of TiO2, leading to dismutation of Ti 2p and inartificial formation of p–n junction on TiO2 surface, which prompted Tl2O selectively interacted with TiO2 in flue gas. Herein, we proposed and verified an effective way to capture gaseous Tl2O, which offered almost the best choice to eliminate Tl emission from flue gas and expanded the function of the TiO2-based catalyst. The formation of p–n junction on commercial V2O5–WO3/TiO2 catalyst under working condition was revealed for the first time, which can be a valuable reference for both heterocatalysis and electro/photocatalysis.