Unravelling the physisorption characteristics of H(2)S molecule on biaxially strained single-layer MoS(2)

Sensing ultra-low levels of toxic chemicals such as H(2)S is crucial for many technological applications. In this report, employing density functional theory (DFT) calculations, we shed light on the underlying physical phenomena involved in the adsorption and sensing of the H(2)S molecule on both pristine and strained single-layer molybdenum disulfide (SL-MoS(2)) substrates. We demonstrate that the H(2)S molecule is physisorbed on SL-MoS(2) for all values of strain, i.e. from −8% to +8%, with a modest electron transfer, ranging from 0.023e(−) to 0.062e(−), from the molecule to the SL-MoS(2). According to our calculations, the electron-donating behaviour of the H(2)S molecule is halved under compressive strains. Moreover, we calculate the optical properties upon H(2)S adsorption and reveal the electron energy loss (EEL) spectra for various concentrations of the H(2)S molecule which may serve as potential probes for detecting H(2)S molecules in prospective sensing applications based on SL-MoS(2).