2D nanomaterials are well suited for energy conversion and storage because of their thickness-dependent physical and chemical properties. However, current synthetic methods for translating 2D materials from the laboratory to industry cannot integrate both advantages of liquid-phase method (i.e., solution processibility, homogeneity, and massive production), and gas-phase method (i.e., high quality and large lateral size). Here, inspired by Chinese Sugar Figure Blowing Art, a rapid "gel-blowing" strategy is proposed for the mass production of 2D nonlayered nanosheets by thermally expanding the viscous gel precursors within a short time (≈1 min). A wide variety of 2D nanosheets including oxides, carbon, oxides/carbon and metal/carbon composites are synthesized on a large scale and with no impurities. Importantly, this method unifies the merits of both liquid-phase and gas-phase syntheses, giving rise to 2D products with high uniformity, nanometer thickness, and large lateral sizes (up to hundreds of micrometers) simultaneously. The success of this strategy highly relies on the speed of "blowing" and control of the amount of reactants. The as-synthesized nanosheet electrodes manifest excellent electrochemical performance for alkali-ion batteries and electrocatalysis. This method opens up a new avenue for economical and massive preparation of good-quality nonlayered 2D nanosheets for energy-related applications and beyond.

A new hollow yet hierarchical MOF structure is developed to construct robust Zn–Mn oxides@carbon hybrids with excellent lithium-ion storage properties.

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The strengthening of polycrystalline metals based on grain refinement has previously been reported to be no longer effective below a critical grain size of approximately 10-15 nm (Refs. 1, 2). That report imposed a limit on grain size tuning for synthesizing stronger materials. Here, we report our study using a diamond-anvil cell coupled with radial X-ray diffraction to track in situ the yield stress and deformation texturing of pure nickel samples with various average grain sizes. Continuous strengthening isobserved from 200 nm to the minimum grain size of 3 nm. Strengthening as a function of grain size is enhanced in the lower grain size regime below 20 nm. We achieved an ultra-high strength of ~ 4.2 gigapascals in nickel, 10 times larger than the values for commercial nickel material. The maximum flow stress of 10.2 gigapascals is reached in 3 nm nickel in the pressure range of this study. Plasticity simulation and transmission electron microscopy (TEM) examination reveal that the high strength observed in 3 nm nickel is caused by the superposition of strengthening mechanisms: partial and full dislocation hardening plus grain boundary plasticity suppression. These results rejuvenate the search for ultra-strong metals via materials engineering.Understanding the strengthening of nanograined metals has been puzzling, as both mixed results of size softening and hardening have been reported [3][4][5][6] . The main challenges in resolving this debate are the difficulty in synthesizing high quality, ultrafine metal samples for traditional tension or hardness tests and making statistically reproducible measurements. Some researchers have pointed out that reported size softening may be related to materials preparation 7 . Porosity, amorphous regions and impurities may be introduced during sample preparation methods like inert gas condensation and electrodeposition, leading to softening in