Structural modification of graphene material by silicon mono-doping and codoping with heteroatoms as sensors for methyl tert-butyl ether (MTBE) as a fuel additive: Insights from DFT

Abstract

Due to the association of methyl tert-butyl ether (MTBE) with groundwater contamination and environmental concerns, fuel additives, and recognized health hazards, including respiratory and central nervous system effects upon exposure, the implementation of mitigating measures becomes imperative on a global scale, particularly through the utilization of nano-oriented materials. Hence, to account for the sensitivity, detection, and adsorption of methyl tert-butyl ether (MTBE) pollutants, this research attempts to investigate the potential of silicon-doped graphene (Si@GP) engineered with boron, nitrogen, and phosphorous atoms by employing density functional groups at the ωB97XD/def2vsp level of theory. Interestingly, the results from several quantum descriptors were analysed to obtain comprehensive knowledge of the interactions between the adsorption complexes. The examined systems (MTBE-Si@GP, MTBE-SiB-GP, MTBE-SiN-GP, and MTBE-SiP-GP) produced Fermi energies of 0.4531 eV, 0.4531 eV, 0.5274 eV, and 0.3936 eV, respectively, providing valuable insights into their electronic structure and sensitivity to MTBE. Subsequent calculations revealed that MTBE-SiP-GP had a work function of 0.3936 eV, making it a superior surface for sensing MTBE compared to the other surfaces considered. The adsorption energies for MTBE-Si@GP, MTBE-SiB-GP, MTBE-SiN-GP, and MTBE-SiP-GP were 8.004 eV, 7.159 eV, 7.785 eV, and 5.027 eV, respectively. Despite their physisorption properties, MTBE-SiP-GP was highlighted as the preferable absorbent at the BSSE level. The comprehensive analysis presented in this study highlights the potential of the MTBE-SiP-GP dopant as a reliable sensing material for monitoring MTBE liquified gas in real-world environments. Our research aims to equip experimental researchers with valuable insights on the silver graphene dopant, and specifically, the MTBE-SiP-GP surface, as a promising candidate for detecting gas sensors.