2D β-tellurene: Increase sensitivity toward toxic cyanide molecules. (December 2021) - Rao, Yifan
Abstract: Cyanide gases are colorless and toxic gases, which are widely used in the industry, thus efficiently detecting them has become a pressing issue. The sensitivity and selectivity of β-tellurene toward cyanide gases are reported in this work. Adsorption energy, charge transfer, and electronic properties of the cyanide gases (HCN, (CN)2, CNBr) as well as common gases (CO2, N2, CO) adsorption systems are calculated based on the density functional theory (DFT). The significantly larger adsorption energy (−0.26 eV for HCN, −0.36 eV for CNBr) and charge transfer (0.11 |e| for HCN, 0.10 |e| for CNBr) show that the tellurene is a well sensitive material for cyanide gases detection. The change of I–V curves made by gas adsorption further confirms the selectivity and sensitivity of tellurene to cyanide gases, especially the HCN. Moreover, different biaxial strains could effectively regulate the adsorption behavior of cyanide gases on tellurene, as the adsorption energy of the HCN molecule is enhanced to be −0.52 eV. Based on these results, we predict that tellurene could be a practical material to detect cyanide gases. Highlights: The tellurene sheet presents high sensitivity and selectivity to cyanide gases. The I–V curves indicate that the selectivity of β-tellurene to cyanide gases. Biaxial strain could regulate the adsorption performances of HCN molecules. The HCN/tellurene system has a proper recovery time at room temperature. The tellurene sheet shows application prospects for cyanide gases detection.