Unveiling the ternary synergistic mechanism of B-N-Al coordinated graphene for enhanced quantum capacitance

Precise tuning of quantum capacitance remains critical for advancing graphene-based materials in modern energy storage and chemical sensing applications. Employing sophisticated first-principles calculations, we systematically investigated mono-doped, binary-doped, and ternary-doped graphene frameworks to elucidate exactly how compositional motifs govern structural evolution, electronic states, charge redistribution, and capacitive behavior. Structural analysis demonstrates that while mono-doping induces minimal lattice distortion, B-N co-doping generates robust local polarization, and Al incorporation drives substantial out-of-plane geometric deformation. Furthermore, electronic structure evaluations conclusively reveal that mono-doping preserves the intrinsic graphene framework while introducing classical p-type or n-type modulation. Conversely, B-N co-doping yields a more balanced frontier structure featuring a distinct gap-like character near the Fermi level. Crucially, integrating Al comprehensively reconstructs these frontier states, introducing prominent near-Fermi-level states alongside reduced band dispersion, strongly indicating enhanced electronic localization and reactivity. In addition, quantum capacitance evaluations confirm that the B-N-Al framework effectively suppresses parasitic capacitance at negative potentials and aggressively concentrates its electronic activity, producing a sharp, dominant capacitance surge of nearly +0.0125 µF cm