부산대학교 도서관

The adsorption behaviors of toxic gas molecules (NO, CO, NO 2 , and NH 3 ) on the graphene-like boron carbide (BC 3 ) are investigated using first-principle density functional theory. The graphene-like BC 3 monolayer is a semiconductor with a band gap of 0.733 eV. It is discovered that all the above gas molecules are chemisorbed on the BC 3 sheet while they retain their molecular forms. It is also revealed that the NO 2 gas molecule could be dissociated into NO and O species through the adsorption process. The amounts of charge transfer upon adsorption of CO and NH 3 gas molecules on the BC 3 are found to be small. The band gap changes in BC 3 as a result of interactions with CO and NH 3 are only 4.63% and 16.7%, indicating that the BC 3 -based sensor has a low and moderate sensitivity to CO and NH 3 , respectively. Contrariwise, upon adsorption of NO or NO 2 on the BC 3 , significant charges are transferred from the molecules to the BC 3 sheet, causing a semiconductor-metal and semiconductor-p type semiconductor transition. Our study suggests that the BC 3 -based sensor has a high potential for NO and NO 2 detection due to the significant conductance changes, moderate adsorption energy, and short recovery time. More excitingly, the BC 3 is a likely catalyst for dissociation of the NO 2 gas molecule. [ABSTRACT FROM AUTHOR]