Fig. 7From: In Situ Fabrication of Bi2Ti2O7/TiO2 Heterostructure Submicron Fibers for Enhanced Photocatalytic ActivitySchematic diagram of a the band energy of Bi2Ti2O7 and TiO2 before contact; b the formation of a p-n junction and the process of electron-hole pairs separation and transfer under visible-light irradiationBack to article page