Formation, electronic properties, and enhanced hydrogen evolution catalytic performance of substitutional defects in 1T PdTe 2

Abstract

Palladium ditelluride (PdTe2), a prominent transition metal dichalcogenide, has emerged as a star material. While its pentagonal layered structure has recently been synthesized, a comprehensive theoretical understanding of defect types (specifically substitutional and vacancy defects), their arrangements, electronic structure, and resulting properties such as catalysis within the 1T phase remains lacking. Employing first-principles calculations, this study investigated the substitutional and vacancy defects in PdTe2. The mechanisms of defect formation, their thermodynamic and kinetics stability, and the corresponding electronic structures were examined. Importantly, the results indicate that defective PdTe2 (especially PdTe defect) exhibits effective hydrogen evolution reaction catalytic performance. These findings highlight the potential of defect engineering for the precise tuning of material properties.