Monolayer PtTe2: A promising candidate for NO2 sensor with ultrahigh sensitivity and selectivity

Abstract Platinum-chalcogen compounds such as platinum dichalcogenides (e.g., PtS2 and PtTe2) have been explored in an effort to study their potential applications in different fields to reduce the use of precious Pt. Herein, the adsorption of NO2, NO, NH3, H2O, CO2, CO and CH4 on monolayer PtTe2 is investigated by using first-principles calculations to exploit its potential applications as gas sensor. Among these gas molecules, only NO2 molecule could be adsorbed on PtTe2 with suitable adsorption strength and apparent charge transfer of 0.4506 e. We further calculate the current-voltage (I–V) relation using the nonequilibrium Green's function (NEGF) method. The transport feature exhibits distinct responses with a dramatic change of I–V relation before and after NO 2 adsorption on monolayer PtTe2: an obvious increase of 259 % in current after NO2 adsorption when the applied voltage is 0.98 V. The findings suggest that monolayer PtTe2 is a promising candidate for the NO2 molecule sensor with high selectivity and sensitivity.