Abstract
Defect sites on oxide semiconductors play a crucial role in promoting photocatalytiperformance and mod-ulating the bandgap structure of photocatalysts.However,the role of interfacial coordinatively unsatu-rated defect sites between metal and oxide in photocatalysis is still under debate.So,we designed an experiment to probe the role of interfacial coordinatively unsaturated defect sites.In this work,a se-ries of Ti/TiO2 photocatalysts with varying concentrations of interfacial Ti3+sites were prepared through an epitaxial growth method under hydrothermal conditions.Through experimental and computational investigations,the roles of interfacial defect sites were discussed in detail.On the one hand,the inter-facial coordinatively unsaturated Ti3+sites could act as visible-light-responsive sites in photocatalytic reactions due to the overlap and hybridization of multiple electronic orbitals.On the other hand,the Ti/TiO2 interface exhibited a certain degree of metallic character near the Fermi level because of the par-tial delocalization and redistribution of electrons,facilitating the charge migration and separation across the metal-oxide interface.Consequently,the obtained Ti/TiO2 catalysts showed notably enhanced charge transfer efficiency and visible light photocatalytic activity compared to their pristine counterparts.This work may provide a new perspective to interfacial defect engineering in classic metal/oxide heterojunc-tion photocatalysts and figure a more precise direction to synthesize higher effective photocatalysts for environmental governance.
基金项目
National Key Re-search and Development Plan of China(2016YFC0209305)
Science and Technology Plans of Tianjin(18PTZWHZ00180)
Major National Science and Technology Projects(2017ZX07106001)
Tianjin Development Program for Innovation and EntrepreneurshipBesides()
NETL
NSTL
万方数据