| Autor: |
Rao BK; Department of Applied Physics, Shri Shankaracharya Technical Campus, Junwani, Bhilai, Chhattisgarh, India., Cabral TLG; Departamento de Física, ICEx, Universidade Federal Fluminense - UFF, Volta Redonda/RJ, Brazil. rgamorim@id.uff.br., Rodrigues DCM; Instituto de Física, Universidade Federal Fluminense, Niterói/RJ, Brazil., de Souza FAL; Departamento de Física, Federal Institute of Education, Science and Technology of Espírito Santo, Ibatiba/ES, Brazil., Scopel WL; Departamento de Física, Universidade Federal do Espírito Santo- UFES, Vitória/ES, Brazil., Amorim RG; Departamento de Física, ICEx, Universidade Federal Fluminense - UFF, Volta Redonda/RJ, Brazil. rgamorim@id.uff.br., Pandey R; Department of Physics, Michigan Technological University, MTU, Houghton/MI, USA. |
| Abstrakt: |
Global air quality has deteriorated significantly in recent years due to large emissions from the transformation industry and combustion vehicles. This issue requires the development of portable, highly sensitive, and selective gas sensors. Nanostructured materials, including defective graphene, have emerged as promising candidates for such applications. In this work, we investigated the B-doped topological line defect in graphene as a sensing material for various gas molecules (CO, CO 2 , NO, and NH 3 ) based on a combination of density functional theory and the non-equilibrium Green's function method. The electronic transport calculations reveal that the electric current can be confined to the line defect region by gate voltage control, revealing highly reactive sites. The B-doped topological line defect is metallic, favoring the adsorption of NO and NH 3 over CO and CO 2 molecules. We notice changes in the conductance after gas molecule adsorption, producing a sensitivity of 50% (16%) for NO (NH 3 ). In addition, the recovery time for nitride gases was calculated for different temperatures and radiation frequencies. At 300 K the ultraviolet (UV) has a fast recovery time compared to the visible (VIS) one by about two orders of magnitude. This study gives an understanding of how engineering transport properties at the microscopic level (by topological line defect and chemical B-doping) leads to promising nanosensors for detecting nitride gas. |
