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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 CaC2 and C6Br6. Brunauer–Emmett–Teller, atomic force microscopy, X‐ray photoelectron spectroscopy, solid‐state 13C 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 sp2‐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.

LiNiCoMnO (NCM) is regarded as a promising material for next-generation lithium ion batteries due to the high capacity, but its practical applications are limited by the poor electronic conductivity. Here, a one-step method is used to prepare carbon coated LiNiCoMnO (NCM/C) by applying active carbon as reaction matrix. TEM shows LiNiCoMnO particles are homogeneously coated by carbon with a thickness about 10 nm. NCM/C delivers the discharge capacity of 191.2 mAh g at 0.5 C (85 mA g) with a columbic efficiency of 91.1%. At 40 C (6800 mA g), the discharge capacity of NCM/C is 54.6 mAh g, whereas NCM prepared through sol-gel route only delivers 13.2 mAh g. After 100 charge and discharge cycles at 1 C (170 mA g) the capacity retention is 90.3% for NCM/C, whereas it is only 72.4% for NCM. The superior charge/discharge performance of NCM/C owes much to the carbon coating layer, which is not only helpful to increase the electronic conductivity but also contributive to inhibit the side reactions between LiNiCoMnO and the liquid electrolyte.

2D γ-graphyne is mechanosynthesized by using benzene and its effective oxygen evolution reaction performance is demonstrated.

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