Light absorption, charge separation and surface reaction are considered as the main processes ofphotocatalysis on one semiconductor, and all of them are demonstrated to be related to the defect statesof photocatalysts...Light absorption, charge separation and surface reaction are considered as the main processes ofphotocatalysis on one semiconductor, and all of them are demonstrated to be related to the defect statesof photocatalysts. This paper will choose Ti02 as model photocatalyst to introduce some basic conceptsand strategies related to defects and methods developed to characterize defects in the past decades.Meanwhile, such strategies as hydrogenation and metal/nonmetal doping intoTi02 will be introduced toextend utilization of solar spectrum and/or to provide active sites. On the contrary, the unfavorable effectof defects such as acting as recombination centers of photogenerated carriers will also be introduced.Some typical methods to characterize the properties of defects are summarized, which contain electronparamagnetic resonance （EPR）, photoluminescence technique （PL）, positron annihilation spectroscopy（PAS）, and so on. We do hope that this review will make a revealing effect on understanding to thefunctions of defects as well as construction of efficient photocatalytic systems in the future.展开更多
基金financially supported by the Basic Research Program of China(973 Program,No.2014CB239403)the National Natural Science Foundation of China(Nos.21633009,21373210,21522306)the priority support from the“Hundred Talents Program”of Chinese Academy of Sciences
文摘Light absorption, charge separation and surface reaction are considered as the main processes ofphotocatalysis on one semiconductor, and all of them are demonstrated to be related to the defect statesof photocatalysts. This paper will choose Ti02 as model photocatalyst to introduce some basic conceptsand strategies related to defects and methods developed to characterize defects in the past decades.Meanwhile, such strategies as hydrogenation and metal/nonmetal doping intoTi02 will be introduced toextend utilization of solar spectrum and/or to provide active sites. On the contrary, the unfavorable effectof defects such as acting as recombination centers of photogenerated carriers will also be introduced.Some typical methods to characterize the properties of defects are summarized, which contain electronparamagnetic resonance （EPR）, photoluminescence technique （PL）, positron annihilation spectroscopy（PAS）, and so on. We do hope that this review will make a revealing effect on understanding to thefunctions of defects as well as construction of efficient photocatalytic systems in the future.
