Singoa, SPhoshoko, Katlego WMogashoa, TNgoepe, PLedwaba, R2026-08-282026-08-282026-072352-4928https://doi.org/10.1016/j.mtcomm.2026.115829http://hdl.handle.net/10204/14912Silicon-based anodes are promising candidates for next-generation lithium-ion batteries owing to their high theoretical capacity, natural abundance, and environmental compatibility. However, their practical implementation is limited by severe volume expansion during lithiation and delithiation, resulting in particle pulverization, loss of electrical contact, and instability of the solid electrolyte interphase (SEI) layer. Doping has emerged as an effective strategy to mitigate these challenges and improve the structural and electrochemical performance of silicon anodes. In this study, the effects of carbon, nitrogen, and fluorine doping on silicon were investigated using the cluster expansion method. Several ordered phases, including SiC, SiF2, SiF5, SiN, SiN2, and SiN5, were predicted to be the most thermodynamically stable structures along the DFT ground-state line. SiN exhibited the most balanced overall performance, as indicated by thermodynamic, mechanical, and dynamical stability, along with semiconducting behaviour and a band gap of 1.76 eV. In contrast, SiN2 displayed semi- metallic conductivity and superior ductility (Pugh’s ratio =2.48, Poisson’s ratio =0.32), although phonon calculations indicated vibrational instability. Carbon doping produced the dynamically stable SiC phase with an enlarged band gap of 2.31 eV but increased brittleness, while fluorine-doped phases exhibited favourable electronic properties but poor mechanical and vibrational stability. The results demonstrate that dopant selection strongly influences the structural, electronic, mechanical, and vibrational properties of silicon, with nitrogen doping offering the most promising route for developing durable silicon-based lithium-ion battery anodes.FulltextenSilicon-based anodesLithium-ion batteriesHigh theoretical capacityVolume expansionParticle pulverizationSolid electrolyte interphaseSEICluster expansionArticleN/A