In this work,a series of BiOBr nanoplates with oxygen vacancies(OVs)were synthesized by a solvothermal method using a water/ethylene glycol solution.The number of OVs and facets of BiOBr were tuned by changing the wat...In this work,a series of BiOBr nanoplates with oxygen vacancies(OVs)were synthesized by a solvothermal method using a water/ethylene glycol solution.The number of OVs and facets of BiOBr were tuned by changing the water/ethylene glycol ratio.Although the role of OVs in photocatalysis has been investigated,the underlying mechanisms of charge transfer and reactant activation remain unknown.To unravel the effect of OVs on the reactant activation and photocatalytic NO oxidation process,in situ diffuse reflectance infrared Fourier transform spectroscopy,so‐called DRIFTS,and theoretical calculations were performed and their results combined.The photocatalytic efficiency of the as‐prepared BiOBr was significantly increased by increasing the amount of OVs.The oxygen vacancies had several effects on the photocatalysts,including the introduction of intermediate energy levels that enhanced light absorption,promoted electron transfer,acted as active sites for catalytic reaction and the activation of oxygen molecules,and facilitated the conversion of the intermediate products to the final product,thus increasing the overall visible light photocatalysis efficiency.The present work provides new insights into the understanding of the role of OVs in photocatalysts and the mechanism of photocatalytic NO oxidation.展开更多
The accumulation of intermediates or final products on TiO2 during photocatalytic volatile organic compounds(VOCs)degradation is typically neglected,despite the fact that it could result in the block of active sites a...The accumulation of intermediates or final products on TiO2 during photocatalytic volatile organic compounds(VOCs)degradation is typically neglected,despite the fact that it could result in the block of active sites and the deactivation of photocatalysts.Inspired from the natural formation of stalactite(CaCO3+H2O+CO2←→Ca(HCO3)2),we fabricated CaCO3 loading TiO2 composites(CCT21)to realize the spontaneously transfer of accumulated final products(CO2 and H2O).Efficient and durable performance for gaseous toluene removal has been demonstrated and the cost of photocatalyst is greatly reduced by the comparison of specific activity.The introduction of CaCO3 induces the interaction between TiO2 and CaCO3 to stimulate abundant activated electrons for the improvement on the adsorption and activation of reactants and the transformation of photogenerated carriers,and most importantly,facilitates the transfer of final products to release active sites and thus suppress the deactivation of TiO2.Furthermore,we develop a facile method to immobilize CCT21 powder on flexible support,which greatly reduces the loss of photocatalysts and correspondingly enables the practical application of TiO2-based products.Therefore,this work presents a novel nature-inspired strategy to address the challenge of deactivation,and advances the development of photocatalytic technology for environmental remediation.展开更多
文摘In this work,a series of BiOBr nanoplates with oxygen vacancies(OVs)were synthesized by a solvothermal method using a water/ethylene glycol solution.The number of OVs and facets of BiOBr were tuned by changing the water/ethylene glycol ratio.Although the role of OVs in photocatalysis has been investigated,the underlying mechanisms of charge transfer and reactant activation remain unknown.To unravel the effect of OVs on the reactant activation and photocatalytic NO oxidation process,in situ diffuse reflectance infrared Fourier transform spectroscopy,so‐called DRIFTS,and theoretical calculations were performed and their results combined.The photocatalytic efficiency of the as‐prepared BiOBr was significantly increased by increasing the amount of OVs.The oxygen vacancies had several effects on the photocatalysts,including the introduction of intermediate energy levels that enhanced light absorption,promoted electron transfer,acted as active sites for catalytic reaction and the activation of oxygen molecules,and facilitated the conversion of the intermediate products to the final product,thus increasing the overall visible light photocatalysis efficiency.The present work provides new insights into the understanding of the role of OVs in photocatalysts and the mechanism of photocatalytic NO oxidation.
基金supported by the National Natural Science Foundation of China(21822601 and 21777011)the Fundamental Research Funds for the Central Universities(ZYGX2019Z021)+2 种基金the 111 Project(B20030)the Plan for“National Youth Talents”of the Organization Department of the Central CommitteeSouthwest Petroleum University Graduate Research Innovation Fund Project(2019cxzd008)。
文摘The accumulation of intermediates or final products on TiO2 during photocatalytic volatile organic compounds(VOCs)degradation is typically neglected,despite the fact that it could result in the block of active sites and the deactivation of photocatalysts.Inspired from the natural formation of stalactite(CaCO3+H2O+CO2←→Ca(HCO3)2),we fabricated CaCO3 loading TiO2 composites(CCT21)to realize the spontaneously transfer of accumulated final products(CO2 and H2O).Efficient and durable performance for gaseous toluene removal has been demonstrated and the cost of photocatalyst is greatly reduced by the comparison of specific activity.The introduction of CaCO3 induces the interaction between TiO2 and CaCO3 to stimulate abundant activated electrons for the improvement on the adsorption and activation of reactants and the transformation of photogenerated carriers,and most importantly,facilitates the transfer of final products to release active sites and thus suppress the deactivation of TiO2.Furthermore,we develop a facile method to immobilize CCT21 powder on flexible support,which greatly reduces the loss of photocatalysts and correspondingly enables the practical application of TiO2-based products.Therefore,this work presents a novel nature-inspired strategy to address the challenge of deactivation,and advances the development of photocatalytic technology for environmental remediation.
