H2S Gas Sensitivity of Doped SbP Monolayer：First Principle Study

The sensing behaviors of monolayer antimonide phosphorus (SbP) for hydrogen sulfide (H2S) are investigated by means of the density functional theory. In this paper, we calculated the best adsorption configuration, charge transfer, adsorption distance, band gap, electronic structure and recovery time of H2S on the SbP monolayer and mental-doped SbP (X-SbP). The calculated results indicate that Al atom replaces Sb atom of SbP (Al-Sb-SbP), adsorption capacity was greatly increased, but the covalent bond formed between the gas molecules and the substrate was not suitable for sensing materials. And though Co or Ni atom could improve the interactions between H2S gas and SbP sheets, the recovery time was too long. It was also not suitable for the sensor material of H2S gas. However, for Pd doped SbP, Pd-Sb and Pd-P doping all exhibit excellent gas sensing performance for H2S gas with the adsorption energy of -0.677eV and -0.520eV, the charge transfer 0.1113e and 0.0930e, the recovery time 0.19s and 5.30and#215;10-4 s, respectively. These characters made Pd-SbP suitable for H2S gas sensing material. Which further analysis we knew that these changes were mainly due to the orbital hybridization between the s, p orbitals of Pd atom and the p orbitals of S atom. Theoretical studies show that Pd-doped SbP is a promising H2S gas sensing material