Low diffusion barrier in black phosphorene/graphdiyne heterostructure for ultrafast Li-ion battery anode

Abstract

Black phosphorene (BlackP) with low diffusion barriers has been extensively researched as one of the new Li-ion batteries (LIBs) anode materials. Nevertheless, the poor mechanical properties and elastic stiffness of BlackP obviously limit its practical application. Thus, owing to the excellent mechanical properties and good elastic stiffness exhibited by Graphdiyne (GDY), the BlackP/GDY Van der Waals (vdW) heterostructure was investigated in our study to overcome those disadvantages on the basis of the density functional theory (DFT). Our results suggest that the BlackP/GDY vdW heterostructure has favorable mechanical properties and high thermodynamic stability with a small lattice mismatch, which is owing to the synergistic effect existed in BlackP and GDY. Besides, the adsorption energy of Li adsorption on the BlackP/GDY vdW heterostructure evidently enhanced along with the changing of the heterostructure from semiconductor to metallic. Moreover, the maximum theoretical storage capacity (384.703 mA h/g) of the BlackP/GDY vdW heterostructure is larger than that of Graphite (372 mA h/g). Above all, the minimum diffusion barrier (0.083 eV) is extremely low, which is vital for achieving ultrafast charge and discharge rates. These favorable advantages suggest that the BlackP/GDY vdW heterostructure is a viable ultrafast LIBs anode material.