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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.

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

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Realizing nitrogen fixation under mild conditions is of great significance to modern industry, agriculture, and society. Several approaches have been attempted to replace the conventional Haber–Bosch process to avoid high temperature and pressure reaction conditions, including photocatalysis, electrochemical catalysis, biomimetic catalysis, and so forth. This work demonstrates a conceptually novel, more cost-effective, and environment-friendly approach to nitrogen fixation by mechanical ball milling of nitrogen gas in water under room temperature and atmospheric pressure. Without extra catalysts, the stainless steel texture of the container and grinding balls has a crucial catalytic effect on direct nitrogen fixation. The presence of the ammonium ion (NH4 +) in the solution is verified by both Nessler’s reagent method and ion chromatography. The process is demonstrated to be a zero-order reaction as (t: hour), and the optimized NH4 + selectivity reaches as high as 99.2%. Water is employed as a proton source instead of hydrogen, preventing the environmental pollution that originated from hydrogen production. Moreover, the characterizations of the resulted powders and theoretical calculations illustrate the superiority of H2O as the proton source, which lowers the energy requirement of the rate-determining step. This work provides a feasible aqueous-phase mechanochemical nitrogen fixation by ball milling N2 and H2O under mild conditions.