Ga掺杂改性ZnO(001)面对CO气敏机理的第一性原理计算

Investigation of Mechanism of CO Gas Sensing of Ga Doped ZnO(001) Using First-Principle Calculation

针对目前在理论上还未能解释清楚的ZnO的气敏机理问题,基于第一性原理结合Castep软件包研究了本征ZnO和Ga掺杂改性ZnO(001)面吸附CO分子后的电子结构和能带结构.研究结果表明:掺杂Ga后ZnO的(001)面的总电子态密度分布与掺杂前类似,带隙中未出现其他的电子态,但掺杂后ZnO表面CO吸附前后的电子态密度发生了显著的变化,价带和导带之间的间隙变小,费米能级进入导带.在此基础上,对Ga掺杂改性ZnO(001)面对CO的气敏机理进行了理论解释.

Aiming at the obscure gas sensing mechanism of ZnO ,the band structure and electronic structure of Ga doped ZnO （001） adsorbed by CO molecule was investigated by first-principle calculations compared with Castep .The results showed ：Distribution of the summary electronic state density of Ga doped ZnO（001） adsorbed by CO molecule was similar to that of intrinsic ZnO（001） ,no other electronic state was observed .However ,a remarkable change of the electronic state density was generated for the Ga doped ZnO（001） adsorbed by CO ,compared with Ga doped ZnO（001） without attached CO molecule . The gap distance between the conductance band and valance band was decreased ,and the Fermi energy was moved into the conductance band .The theoretics analysis of the CO gas sensing mechanism of Ga doped ZnO（001） was explained in detail .