ScholarWorks@성균관대학교

초록

Silicon (Si) is a compelling anode for next-generation lithium-ion batteries (LiBs) because of its ultrahigh theoretical capacity, yet its deployment is fundamentally limited by drastic volume expansion during cycling that triggers mechanical pulverization, unstable interphase growth, and rapid capacity decay. Here, we report a robust molybdenum-doped carbon (C–Mo) matrix coating, synthesized from polyvinylpyrrolidone and ammonium molybdate via solvent-assisted deposition and controlled carbonization, to stabilize porous Si (PSi) anodes. The resulting conformal coating uniformly encapsulates PSi and in situ generates conductive Mo2C/MoO2 nanophases embedded within the carbon matrix, imparting simultaneous mechanical reinforcement and accelerated charge transport. Structural and surface analyses verify homogeneous Mo incorporation and phase formation, while electrochemical diagnostics demonstrate markedly improved interfacial kinetics with reduced charge-transfer resistance and enhanced Li+ diffusion relative to undoped carbon coatings. Consequently, the optimized PSi@C–Mo electrode delivers substantially improved cycling durability and high-rate capability, retaining 73% of its capacity (1062 mAh g−1) after 80 cycles at 100 mA g−1. This work suggests that Mo-containing carbon matrices are a promising coating strategy for improving the structural and electrochemical performance of Si anodes.

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