Two-dimensional carbon rich titanium carbide (TiC3) as a high-capacity anode for potassium ion battery

Abstract

In recent years, two-dimensional (2D) materials, particularly MXenes such as titanium carbide, have gained significant interest for energy storage applications. This study explores the use of potassium-adsorbed TiC3 nanosheets as potential anode materials for potassium ion batteries (KIBs), utilizing first-principles calculations. The investigated electronic, mechanical, and thermal properties of TiC3 demonstrate its suitability as an anode material. The incorporation of potassium into the host material enhances electronic conductivity while maintaining a stable layered structure. Our findings reveal promising adsorption behavior of potassium in TiC3, leading to a high theoretical specific capacity of 958 mAh/g, coupled with a low energy barrier of 0.19 eV for potassium migration, which is indicative of superior electrochemical performance. Moreover, despite the high potassium content, the electrode material shows limited volume expansion of 11.3 %, suggesting good cyclability. Additionally, the equilibrium distance between potassium and TiC3, measured at 3.11 & ring;A, exceeds that of lithium and TiC3 (2.56 & ring;A), potentially augmenting the material's flexibility. Consequently, TiC3 emerges as a promising candidate for KIB anode materials.