Strain-Modulated Conductivity and Work Function on Thin Crystals of Mo2C

Abstract

Thin transition metal carbides (TMCs) exhibit a favorable combination of electronic and mechanical properties that makes them attractive for applications ranging from flexible energy storage to electromagnetic shielding. However, the influence of strain on key electronic characteristics such as conductivity and work function has not yet been elucidated. Here, we present a combined experimental and computational study of surface electronics on thin crystals of molybdenum carbide (Mo2C). Conductive atomic force microscopy (C-AFM) and Kelvin probe force microscopy (KPFM) performed on rippled regions of crystal surfaces reveal a significant increase in electrical conductivity and a notable reduction in work function under tensile strains of 1% and below. Ab initio calculations confirm the trends observed in the experiments, pointing toward increased density of states (DOS), enhanced mobility, and reduced work function under tensile strain. Our work highlights the potential of strain engineering for tuning the electronic characteristics of thin TMCs.