A theoretical study for the performance evaluation of the two-dimensional carbon Kagome lattice as an anode material for lithium-ion batteries

Abstract

Securing high specific capacity in two-dimensional (2D) carbon allotrope materials in lithium-ion batteries (LIBs) is crucial for their use as well-balanced anode materials. Motivated by this, we utilize first-principles calculations to systematically investigate the potential of a carbon Kagome lattice (CKL) monolayer as an effective material for LIBs. A 2D CKL demonstrates excellent energetic, dynamic, and thermal stability. Lithium adsorption analysis demonstrates strong anchoring capability toward Li ions, characterized by a relatively high adsorption energy (−2.68 eV), arising from pronounced electron transfer (0.943 e) between Li ions and the CKL framework. Notably, the CKL presents a low Li diffusion barrier (0.18 eV), indicating fast ion transport kinetics that are highly desirable for high-rate battery operation. Furthermore, the maximum configuration of the CKL delivers a high theoretical capacity of 1115.7 mAh g⁻¹, simultaneously maintaining robust structural stability throughout Li-ion adsorption and desorption. Meanwhile, the calculated average open-circuit voltage is 1.3 V, which is comparable to that of TiO₂ (1.5–1.8 V) and h-AlC (1.38 V). Furthermore, the CKL still maintains good thermal stability even under the maximum Li storage capacity at 500 K. These merits demonstrate the CKL to be a promising and well-balanced carbon anode material and provide useful insights for the rational design of advanced anode materials for LIBs.