Blue phosphorene/graphdiyne heterostructure as a potential anode for advanced lithium-ion batteries: First-principle investigation

Abstract

Blue phosphorene has triggered enormous research effort as an anode for Li-ion batteries due to its large surface and high capacity. However, its application is hindered by poor electrical conductivity, mechanical properties and mobility. Graphdiyne exhibits excellent mechanical properties and high storage capacity but low Li-ion mobility. Herein, we designed blue phosphorene/graphdiyne (BlueP/GDY) heterostructure as a potential anode material for LIB based on denstity functional theory. We demonstrated that BlueP/GDY heterostructure exhibits good thermodynamics stability and enhanced elastic stiffness (Young’s modulus is 215.9 N/m), which can effectively avoid electrode cracking and pulverization. Synergistic effect between BlueP and GDY significantly enhanced binding strength of Li for composite compared with isolated BlueP and GDY. The transition of semiconducting to metallic induced by Li intercalation suggested better metallic conductivity for fast electron transport. Furthermore, BlueP/GDY heterostructure delivers high theoretical specific capacity (761.76 mA·h·g−1) and rather small Li-ion diffusion energy barriers (0.11 eV), which is estimated to be 105 times faster than that on isolated BlueP and GDY at room temperature, indicating excellent rate performance for BlueP/GDY anode. Therefore, it is expected that BlueP/GDY heterostructure has great potential in LIBs with excellent mechanical stability, good electrical conductivity, high capacity and fast Li-ion mobility.