First-principles design of noble metal (Rh and Pd) dispersed Janus WSTe monolayer for toxic gas sensing applications

Toxic gas sensing is always a research hotspot in environmental protection, agricultural monitoring, industrial manufacture and human safety. In this work, we perform the first-principle simulations upon Rh- and Pd-dispersed WSTe (Rh- and Pd-WSTe) monolayer and their sensing performance upon CO, SO2 and NH3. The single Rh and Pd atom dispersing property on the pristine WSTe monolayer is investigated initially, followed by their gas adsorption performance, and finally uncovering the electronic property and sensing potential of such two novel materials. The findings in this work illustrate chemisorption of Rh- and Pd-WSTe monolayer upon three gas species, and their recovery property are analyzed to uncover their strong potential as SO2 and CO gas sensor, respectively, with the reusability by heating process under 498 K for several seconds, as well as the more suitability of Pd-WSTe monolayer as a NH3 gas sensor. Moreover, the effect of biaxial strains for gas adsorptions on Rh- and Pd-WSTe monolayer are analyzed, to identify their stronger sensing performance under the positive biaxial strains for three gas species, especially for the Rh-WSTe monolayer. These findings are critical to manifest the favorable sensing potential of Rh- and Pd-WSTe monolayer upon such three toxic gases, shedding light on the further explorations on WSTe-based materials for gas adsorption, catalytic and sensing applications.