Unlocking the Role of Covalent Bonding and the Gradient of Hydrogen Bonding in Stabilizing Si-Based Anodes

Stabilizing silicon anodes against volumetric stress demands covalent hydrogen–covalent bond interactions. Therefore, dual covalent and gradient hydrogen bonding through amino acids was developed within carbon-coated silicon and MXene-based hybrids. The glycine-based hybrid having strong covalent bonding and lower hydrogen-bonding sites exhibited the best electrochemical performance by presenting higher lithium diffusion, rate capability, and higher capacity of 551.5 mAh g–1 at 500 mA g–1 after 250 cycles. The SiCGM hybrid showed the best electrochemical performance, reinforcing that controlled bonding is key to meeting silicon-based anode stability demands.