BN-doping in anode materials: a theoretical route to high-performance Li, Na and K-ion batteries

Abstract

This study presents a comprehensive computational investigation of pristine and BN-doped polycyclic aromatic hydrocarbons (BN_PAHs) as potential anode materials for alkali metal-ion batteries (MIBs), including lithium-, sodium-, and potassium-ion systems. Using molecular electrostatic potential (MESP) analysis, Mulliken charge analysis, spin density distribution, and adsorption energy calculations, we examined the interactions of BN_PAHs with Li, Na, and K in both atomic and cationic forms. Results reveal that BN-doping enhances charge transfer and electron affinity, enabling stronger non-covalent interactions and tuning of adsorption strength. Charge transfer trends follow K > Na > Li for metal atoms and Li⁺ > Na⁺ > K⁺ for cations. A strong linear correlation (R > 0.97) between the MESP change at the metal nucleus (ΔV_M⁺) and adsorption energy confirms ΔV_M⁺ as a reliable descriptor of cation–π interactions. Cell voltage (V_cell) analysis identifies the (1BN_2⋯M) complex as the most promising anode material, delivering the highest voltages across systems: 1.41 V (LIB) and 0.81 V (PIB). These findings highlight the tunability and efficiency of BN-doped PAHs as next-generation organic anodes for MIBs.