Facile Carburization Engineering to Construct Porous Locally Carbonized MoO3 Composite with Long-Term Stable Lithium Storage Capacity

Abstract

Regulating electrode materials through structural design and compositional optimization can significantly enhance key performance metrics for lithium-ion batteries (LIBs), such as dynamic performance, cycling stability, and service life. Molybdenum trioxide (MoO₃) has emerged as a promising anode material for LIBs due to its high theoretical Li⁺ storage capacity (1117 mAh g^–1), low cost, and outstanding chemical stability. Nevertheless, the electrochemical performance of MoO₃ anodes is limited by poor intrinsic conductivity and significant volume expansion during cycling. To address the crucial issues, this study employs a simple carburization strategy to synthesize a three-dimensional porous carbon-supported, locally carbonized MoO₃ composite (MoO₃/Mo₂C/C) through strong coordination between Mo⁶⁺ metal cations and citric acid ligands. The elaborate structural design significantly enhances both conductivity and structural stability, leading to remarkable improvements in cycling performance. After 600 cycles, the composite anode maintains a discharge capacity of 1038.9 mAh g^–1 at 0.5 A g^–1 with a Coulombic efficiency of 99.97%, which is nearly 10 times that of the unmodified MoO₃ anode. In addition, a full battery is assembled with a LiFePO₄ cathode and the as-prepared MoO₃/Mo₂C/C anode to evaluate the practicality and reliability. As expected, the full battery delivers a high capacity of 122.1 mAh g^–1 at a current density of 0.1 A g^–1, demonstrating the promising strategy for the design of MoO₃ electrode materials.