First-principles study on the C-excess C3B for its potential application in sensing NO2 and NO

• DOI: 10.1016/j.apsusc.2020.145611
• Publication Date: 2020-02-01T16:07:05Z
• Authors: Xiaoye Sun; Zhe Song; Qin Liu; Bo Xiao; Yanchun Li; Jianbo Cheng; Zhenbo Liu; Xin Yang; Xuefang Yu; Qingzhong Li
• Keywords: 02 engineering and technology; 0210 nano-technology

Abstract Recently, C3B monolayer has attracted much attention due to its potential applications in many fields. In this work, we have further explored its application as gas sensor. Since the experimentally synthesized C3B is usually C excess, we have theoretically studied the adsorption behaviors of N2, O2, CO2, H2O, CH4, NO, NO2, CO and NH3 on C-excess C3B (C3+xB, x = 0.1, 0.2, 0.3, 0.4 and 0.6), the cases on pure C3B are also calculated for the comparison. Our results reveal that C3+xB undergoes the changes from metal to semiconductor after the adsorption of NO2 and NO, which implies its high sensitivity towards these two molecules. Among all the gases, only NO, NO2, CO and NH3 could adsorb on the C3+xB, and CO/NH3 and NO/NO2 prefer to adsorb on the B-site and doped C-site in C3+xB, respectively. In this regard, C3+xB exhibits the high selectivity towards NO and NO2 irrespective of the existence CO, NH3 and other gases. Also, the adsorbed gases on C3+xB could be easily removed by injecting electrons into the system. Based on these results, we proposed that the C-excess C3+xB is a promising reusable material as NO2 and NO sensor with high sensitivity and selectivity.