First-principles design of PtPd bimetal dispersed WTe2 monolayer for sensing thermal runaway gases: Enhanced performance against single Pt or Pd dispersion

Abstract

To conduct the early-monitoring of thermal runaway for the Li-ion battery (LIBs), this work purposes PtPd bimetal dispersed WTe2 (PtPd-WTe2) monolayer as a promising sensing material to realize the high-sensitive detection of thermal runaway gases (H2, CO, CO2, C2H2 and C2H4). The adsorption behavior of PtPd-WTe2 monolayer upon such five gas molecules are compared with single Pt- and Pd-dispersed WTe2 monolayer from the first-principles insight to highlight the combined catalytic property of two noble metal atoms. Results reveal that Pt-, Pd- and PtPd-WTe2 monolayer all behave good chemical and thermal stability at 498 K with good binding force between the noble metal atom(s) and the pristine WTe2 surface. Besides, PtPd-WTe2 monolayer behaves much enhanced adsorption performance with more negative adsorption energy and much higher sensing response with larger bandgap changing rate than Pt- and Pd-WTe2 monolayer upon five typical gas molecules. Moreover, the desorption property analysis manifests the necessity conducting the heating process to realize the reusability of PtPd-WTe2 monolayer for gas sensing. These findings manifest the strong potential of PtPd-WTe2 monolayer as a resistive gas sensor for detections of the thermal runaway gas species thus evaluating the operation status of the LIBs, which may stimulate the further deeper investigations about WTe2-based materials for gas sensing applications across multiple fields.