Mechanochemical Synthesis of γ‐Graphyne with Enhanced Lithium Storage Performance

Abstract γ‐Graphyne is a new nanostructured carbon material with large theoretical Li + storage due to its unique large conjugate rings, which makes it a potential anode for high‐capacity lithium‐ion batteries (LIBs). In this work, γ‐graphyne‐based high‐capacity LIBs are demonstrated experimentally. γ‐Graphyne is synthesized through mechanochemical and calcination processes by using CaC 2 and C 6 Br 6 . Brunauer–Emmett–Teller, atomic force microscopy, X‐ray photoelectron spectroscopy, solid‐state 13 C NMR and Raman spectra are conducted to confirm its morphology and chemical structure. The sample presents 2D mesoporous structure and is exactly composed of sp and sp 2 ‐hybridized carbon atoms as the γ‐graphyne structure. The electrode shows high Li + storage (1104.5 mAh g −1 at 100 mA g −1 ) and rate capability (435.1 mAh g −1 at 5 A g −1 ). The capacity retention can be up to 948.6 (200 mA g −1 for 350 cycles) and 730.4 mAh g −1 (1 A g −1 for 600 cycles), respectively. These excellent electrochemical performances are ascribed to the mesoporous architecture, large conjugate rings, enlarged interplanar distance, and high structural integrity for fast Li + diffusion and improved cycling stability in γ‐graphyne. This work provides an environmentally benign and cost‐effective mechanochemical method to synthesize γ‐graphyne and demonstrates its superior Li + storage experimentally.