Due to the extremely large surface to bulk ratio,the properties of single layer(SL)MoS_(2)are largely determined by its interaction with environment.One critical interaction process that has been intensively investiga...Due to the extremely large surface to bulk ratio,the properties of single layer(SL)MoS_(2)are largely determined by its interaction with environment.One critical interaction process that has been intensively investigated is the oxidation process of MoS_(2).Despite numerous previous explorations,the detailed mechanism regarding how MoS_(2)reacts with oxygen is still not well understood.In this work,we systematically investigate the impact of intrinsic and pre-created defects on the oxidation process of SL MoS_(2).For pristine SL MoS_(2),the oxidation is found to initiate near point defects and grain boundaries,leading to the formation of triangle pits in the basal plane and cracks near the grain boundaries.The pre-created defects introduced by ion irradiation are found to serve as the oxidation center,resulting in a more uniform oxidation process.The oxidation is found to introduce p-type doping in the SL MoS_(2),leading to the blue shift of Raman and photoluminescence(PL)spectra.The shift is found to be more for the region near the grain boundary and for the samples with more pre-created defects.Our results suggest that the presence of defects can strongly promote the oxidation reaction of SL MoS_(2)in ambient condition,which significantly affects the stability and functionality of materials.展开更多
基金the National Natural Science Foundation of China(Grant Nos.11605063,11975102 and 51672011)Guangzhou Science and Technology Program General Projects(Grant No.201707010146)+4 种基金IAEA(CRP No.F11020 and Contract No.21063)the Fundamental Research Funds for the Central Universities(Grant No.2018MS40)State Key Laboratory of Pulp and Paper Engineering(Grant No.2018TS08)Guangdong Pearl River Talent Program(Grant No.2017GC010281)the Guangdong Innovative and Entrepreneurial Research Team Program(Grant No.2014ZT05N200)。
文摘Due to the extremely large surface to bulk ratio,the properties of single layer(SL)MoS_(2)are largely determined by its interaction with environment.One critical interaction process that has been intensively investigated is the oxidation process of MoS_(2).Despite numerous previous explorations,the detailed mechanism regarding how MoS_(2)reacts with oxygen is still not well understood.In this work,we systematically investigate the impact of intrinsic and pre-created defects on the oxidation process of SL MoS_(2).For pristine SL MoS_(2),the oxidation is found to initiate near point defects and grain boundaries,leading to the formation of triangle pits in the basal plane and cracks near the grain boundaries.The pre-created defects introduced by ion irradiation are found to serve as the oxidation center,resulting in a more uniform oxidation process.The oxidation is found to introduce p-type doping in the SL MoS_(2),leading to the blue shift of Raman and photoluminescence(PL)spectra.The shift is found to be more for the region near the grain boundary and for the samples with more pre-created defects.Our results suggest that the presence of defects can strongly promote the oxidation reaction of SL MoS_(2)in ambient condition,which significantly affects the stability and functionality of materials.
