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...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/TiO_(2) photocatalysts with varying concentrations of interfacial Ti^(3+)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 Ti^(3+)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/TiO_(2) 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/TiO_(2) 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.展开更多
The Co_(3)O_(4) decorated TiO_(2) nanotube arrays(NTAs)coatings are fabricated by the combination of anodization and impregnating methods.It is found that the introduction of Co_(3)O_(4) can reduce the diffraction int...The Co_(3)O_(4) decorated TiO_(2) nanotube arrays(NTAs)coatings are fabricated by the combination of anodization and impregnating methods.It is found that the introduction of Co_(3)O_(4) can reduce the diffraction intensity of(101)plane of the TiO_(2) and accelerate the separation of photogenerated electron/hole pairs.In addition,the open circuit potential(OCP)and the corrosion potential of 304 stainless steel(304SS)with or without Co_(3)O_(4) decorated TiO_(2) NTAs were measured under visible light,which indicated the 304SS coupled with Co_(3)O_(4) decorated TiO_(2) NTAs had better anticorrosion performance than that of the 304SS or the 304SS coupled with pure TiO_(2) NTAs.The enhancement of the cathodic protection performance of the Co_(3)O_(4) decorated TiO_(2) NTAs can be ascribed to the matched energy levels and strong interaction between Co_(3)O_(4) and TiO_(2) NTAs,and the improvement of light absorption.展开更多
基金financialy supported by the National Key Research and Development Plan of China (No.2016YFC0209305)the Science and Technology Plans of Tianjin (No.18PTZWHZ00180)+1 种基金the Major National Science and Technology Projects (No.2017ZX07106001)the Tianjin Development Program for Innovation and Entrepreneurship。
文摘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/TiO_(2) photocatalysts with varying concentrations of interfacial Ti^(3+)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 Ti^(3+)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/TiO_(2) 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/TiO_(2) 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This work was supported by the National Natural Science Foundation of China(Nos.21875026,21878031)the Revitalization Talents Program of China(No.XLYC1802124)+1 种基金the Liaoning BaiQianWan Talents Program,China,the Scientific Research Fund of the Educational Department of Liaoning Province,China(No.J2019013)the Joint Research Fund of Liaoning-Shenyang National Laboratory for Materials Science,China(No.2019JH3/30100034).
文摘The Co_(3)O_(4) decorated TiO_(2) nanotube arrays(NTAs)coatings are fabricated by the combination of anodization and impregnating methods.It is found that the introduction of Co_(3)O_(4) can reduce the diffraction intensity of(101)plane of the TiO_(2) and accelerate the separation of photogenerated electron/hole pairs.In addition,the open circuit potential(OCP)and the corrosion potential of 304 stainless steel(304SS)with or without Co_(3)O_(4) decorated TiO_(2) NTAs were measured under visible light,which indicated the 304SS coupled with Co_(3)O_(4) decorated TiO_(2) NTAs had better anticorrosion performance than that of the 304SS or the 304SS coupled with pure TiO_(2) NTAs.The enhancement of the cathodic protection performance of the Co_(3)O_(4) decorated TiO_(2) NTAs can be ascribed to the matched energy levels and strong interaction between Co_(3)O_(4) and TiO_(2) NTAs,and the improvement of light absorption.
