Adsorption and sensing properties of Pd-doped Janus HfSSe monolayer for thermal runaway gases in lithium-ion batteries: A DFT study

Detecting thermal runaway gases in lithium-ion batteries (LIBs) is an effective means of identifying early battery failures and is significant in ensuring the safe operation of LIBs. This work investigated the adsorption characteristics of CO2, 2 , CO, H2, 2 , CH4, 4 , C2H2, 2 H 2 , C2H4, 2 H 4 , and H2O 2 O on intrinsic and Pd-doped HfSSe monolayers using density functional theory (DFT). Our calculations showed that all gases were physically adsorbed on the intrinsic HfSSe monolayer, but the Pd-doped HfSSe monolayer had an enhanced adsorption effect for gas molecules. Additional computations of the band structure, deformation charge density, density of states, and frontier molecular orbitals revealed that the Pd-HfSSe monolayer demonstrated superior CO and C2H4 2 H 4 adsorption and sensing capabilities. The analysis of recovery time revealed that Pd-HfSSe may be used as a gas sensor for identifying C2H4. 2 H 4 . This study provides a theoretical basis for applying Pd-HfSSe as a gas sensor to detect thermal runaway gases in LIBs.