Novel 2D transition metal carbo-chalcogenides as anode materials: A comparative study of Sc2S2C and Sc2Se2C monolayers

Abstract

The increasing global demand for efficient energy storage systems has prompted extensive research aimed at enhancing the performance of rechargeable batteries, particularly through the discovery and application of novel two-dimensional (2D) materials. Transition metal carbo-chalcogenides (TMCC), a class of nanosheets, show great promise due to their high electrical conductivity and significant lithium storage capacity, making them excellent candidates for anode materials in metal-ion batteries. In this study, we investigate and compare the structural stability and electrochemical performance of two such monolayers, Sc₂S₂C and Sc₂Se₂C, as anodes in rechargeable lithium-ion and sodium-ion batteries. Using first-principles density functional theory (DFT) calculations, we predict low diffusion barriers for lithium ion migration on both surfaces, enabling rapid ion diffusion and promising fast charge/discharge rates. Furthermore, the capacity for multi-layer lithium adsorption results in storage capacities exceeding 600 mAh/g, with an average open-circuit voltage (OCV) around 0.6 V for both materials, positioning them as highly suitable for anode applications. Our comprehensive analysis highlights the potential of Sc₂S₂C and Sc₂Se₂C monolayers as high-performance anode materials for next-generation energy storage systems.