TY - JOUR
T1 - Theoretical study of NO2 adsorption on SiCNT and P-doped SiCNT
AU - Lin, Wang qiang
AU - Xiao, Song tao
AU - Li, Hui bo
AU - Ouyang, Ying gen
AU - Wang, Ling yu
AU - Wang, Qiang
AU - Chen, Guang hui
N1 - Publisher Copyright:
© 2020
PY - 2021/3
Y1 - 2021/3
N2 - The release of NO2 into atmosphere, mainly coming from the combustion of fuel, has brought serious pollution on the environment. In order to detect and remove it, the adsorptions of NO2 on pristine silicon carbon nanotube (SiCNT) and phosphorus-doped silicon carbon nanotube (P-SiCNT) were investigated theoretically based on density functional theory (DFT) and grand-canonical Monte Carlo (GCMC) method, including the geometrical structures, adsorption energies, electronic structures, sensitivities, recovery time and the selectivity for the adsorption of NO2 in high humidity environment. To dope the SiCNT, a carbon or silicon atom was replaced with a phosphorus atom to build PC-SiCNT and PSi-SiCNT. It is found that when NO2 is adsorbed on the surface or inside SiCNT, PC-SiCNT and PSi-SiCNT, respectively, the largest adsorption energies are −34.53 kcal/mol for M1-NO2-SiCNT, −64.41 kcal/mol for M1-NO2-PC-SiCNT, −57.04 kcal/mol for M1-NO2-PSi-SiCNT, respectively, which are all belong to chemical adsorption. For the adsorption NO2 on SiCNT to form M1-NO2-SiCNT and NO2-SiCNT, the adsorption systems keep p-type semiconductor properties with a slight decrease of band gap. While for the adsorption NO2 on PC-SiCNT and PSi-SiCNT to form M1-NO2-PC-SiCNT, NO2-PC-SiCNT, M1-NO2-PSi-SiCNT and NO2-PSi-SiCNT, the adsorption systems are converted to p-type semiconductor from metal. Furthermore, the sensitivities were also calculated based on the band gap, and it is found that PC-SiCNT and PSi-SiCNT have superior sensing performance in detecting NO2. Therefore, P-SiCNTs may have potential application not only adsorbent but also gas sensors of NO2. For the adsorption configurations with the largest adsorption energies, the suitable desorption temperatures within 1 min are 553 K for M1-NO2-SiCNT, 1023 K for M1-NO2-PC-SiCNT and 913 K for M1-NO2-PSi-SiCNT, respectively, which makes the recycle of SiCNT, PC-SiCNT and PSi-SiCNT possible. Meanwhile, the effect of the humidity was also explored, and it is found that the humidity has slight effect on the adsorption of NO2 for above nanotubes.
AB - The release of NO2 into atmosphere, mainly coming from the combustion of fuel, has brought serious pollution on the environment. In order to detect and remove it, the adsorptions of NO2 on pristine silicon carbon nanotube (SiCNT) and phosphorus-doped silicon carbon nanotube (P-SiCNT) were investigated theoretically based on density functional theory (DFT) and grand-canonical Monte Carlo (GCMC) method, including the geometrical structures, adsorption energies, electronic structures, sensitivities, recovery time and the selectivity for the adsorption of NO2 in high humidity environment. To dope the SiCNT, a carbon or silicon atom was replaced with a phosphorus atom to build PC-SiCNT and PSi-SiCNT. It is found that when NO2 is adsorbed on the surface or inside SiCNT, PC-SiCNT and PSi-SiCNT, respectively, the largest adsorption energies are −34.53 kcal/mol for M1-NO2-SiCNT, −64.41 kcal/mol for M1-NO2-PC-SiCNT, −57.04 kcal/mol for M1-NO2-PSi-SiCNT, respectively, which are all belong to chemical adsorption. For the adsorption NO2 on SiCNT to form M1-NO2-SiCNT and NO2-SiCNT, the adsorption systems keep p-type semiconductor properties with a slight decrease of band gap. While for the adsorption NO2 on PC-SiCNT and PSi-SiCNT to form M1-NO2-PC-SiCNT, NO2-PC-SiCNT, M1-NO2-PSi-SiCNT and NO2-PSi-SiCNT, the adsorption systems are converted to p-type semiconductor from metal. Furthermore, the sensitivities were also calculated based on the band gap, and it is found that PC-SiCNT and PSi-SiCNT have superior sensing performance in detecting NO2. Therefore, P-SiCNTs may have potential application not only adsorbent but also gas sensors of NO2. For the adsorption configurations with the largest adsorption energies, the suitable desorption temperatures within 1 min are 553 K for M1-NO2-SiCNT, 1023 K for M1-NO2-PC-SiCNT and 913 K for M1-NO2-PSi-SiCNT, respectively, which makes the recycle of SiCNT, PC-SiCNT and PSi-SiCNT possible. Meanwhile, the effect of the humidity was also explored, and it is found that the humidity has slight effect on the adsorption of NO2 for above nanotubes.
KW - Adsorption
KW - Density functional theory
KW - Phosphorous-doped silicon carbide nanotube
KW - Recovery time
KW - Selectivity
KW - Sensitivity
UR - http://www.scopus.com/inward/record.url?scp=85096381497&partnerID=8YFLogxK
U2 - 10.1016/j.physe.2020.114519
DO - 10.1016/j.physe.2020.114519
M3 - 文章
AN - SCOPUS:85096381497
SN - 1386-9477
VL - 127
JO - Physica E: Low-Dimensional Systems and Nanostructures
JF - Physica E: Low-Dimensional Systems and Nanostructures
M1 - 114519
ER -