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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Transition metal carbonates (TMCs) with complex composition and robust hybrid structure hold great potential as high-performance electrode materials for lithium-ion batteries (LIBs). However, poor ionic/electronic conductivities and large volume changes of TMCs during lithiation/delithiation processes have hindered their applications. Herein, single-phase MnCo mixed carbonate composites encapsulated by reduced graphene oxide (Mn x Co 1−x CO 3 / RGO), in which Mn and Co species are distributed randomly in one crystal structure, are successfully synthesized through a facial liquid-state method. When evaluated as LIB anodes, the Mn x Co 1−x CO 3 /RGO composites exhibit enhanced electrochemical performance compared with the reference CoCO 3 / RGO and MnCO 3 /RGO. Specifically, the Mn 0.7 Co 0.3 CO 3 /RGO delivers an ultrahigh capacity of 1454 mA h g −1 after 130 cycles at 100 mA g −1 and exhibits an ultralong cycling stability (901 mA h g −1 after 1500 cycles at 2000 mA g −1 ). This is the best lithium storage performance among carbonatebased anodes reported up to date. Such superb performance is attributed to the hybrid structure and enhanced electroconductivity due to the integration of Co and Mn into one crystal structure, which is complemented by electrochemical impedance spectroscopy and density functional theory calculations. The facile synthesis, promising electrochemical results, and scientific understanding of the Mn x Co 1−x CO 3 /RGO provides a design principle and encourages more research on TMCs-based electrodes.

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

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Introduction. Broadcasting a suicide attempt on social media has become a public health concern in many countries, particularly in China. In these cases, social media users are likely to be the first to witness the suicide attempt, and their attitudes may determine their likelihood of joining rescue efforts. This paper examines Chinese social media (Weibo) users’ attitudes towards suicide attempts broadcast on Weibo.Methods. A total of 4,969 Weibo posts were selected from a customised Weibo User Pool which consisted of 1.06 million active users. The selected posts were then independently coded by two researchers using a coding framework that assessed: (a) Themes, (b) General attitudes, (c) Stigmatising attitudes, (d) Perceived motivations, and (e) Desired responses.Results and Discussion. More than one third of Weibo posts were coded as “stigmatising” (35%). Among these, 22%, 16%, and 15% of posts were coded as “deceitful,” “pathetic,” and “stupid,” respectively. Among the posts which reflected different types of perceived motivations, 57% of posts were coded as “seeking attention.” Among the posts which reflected desired responses, 37% were “not saving” and 28% were “encouraging suicide.” Furthermore, among the posts with negative desired responses (i.e., “not saving” and “encouraging suicide”), 57% and 17% of them were related to different types of stigmatising attitudes and perceived motivations, respectively. Specifically, 29% and 26% of posts reflecting both stigmatising attitudes and negative desired responses were coded as “deceitful” and “pathetic,” respectively, while 66% of posts reflecting both perceived motivations, and negative desired responses were coded as “seeking attention.” Very few posts “promoted literacy” (2%) or “provided resources” (8%). Gender differences existed in multiple categories.Conclusions. This paper confirms the need for stigma reduction campaigns for Chinese social media users to improve their attitudes towards those who broadcast their suicide attempts on social media. Results of this study support the need for improved public health programs in China and may be insightful for other countries and other social media platforms.

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