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High performance nanocomposites require well dispersion and high alignment of the nanometer-sized components, at a high mass or volume fraction as well. However, the road towards such composite structure is severely hindered due to the easy aggregation of these nanometer-sized components. Here we demonstrate a big step to approach the ideal composite structure for carbon nanotube (CNT) where all the CNTs were highly packed, aligned, and unaggregated, with the impregnated polymers acting as interfacial adhesions and mortars to build up the composite structure. The strategy was based on a bio-inspired aggregation control to limit the CNT aggregation to be sub 20–50 nm, a dimension determined by the CNT growth. After being stretched with full structural relaxation in a multi-step way, the CNT/polymer (bismaleimide) composite yielded super-high tensile strengths up to 6.27–6.94 GPa, more than 100% higher than those of carbon fiber/epoxy composites, and toughnesses up to 117–192 MPa. We anticipate that the present study can be generalized for developing multifunctional and smart nanocomposites where all the surfaces of nanometer-sized components can take part in shear transfer of mechanical, thermal, and electrical signals.

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Hydrogen (H2) as an environmentally friendly and sustainable energy carrier has been regarded as one of the most promising alternatives to carbon‐based fossil fuels. Electrochemical water splitting powered by renewable electricity provides a promising strategy for H2 production, but its energy efficiency is strongly limited by the kinetically sluggish anodic oxygen evolution reaction (OER), which consumes ≈90% electricity in the water‐splitting process. A new strategy is urgently needed to reduce its energy consumption. Small‐molecule electro‐oxidation reactions that replace OER have attracted increasing attention due to the advantages of low theoretical thermodynamic potential and the benefit of producing value‐added chemicals compared with OER. Hybrid electrolysis systems, by coupling cathodic hydrogen evolution reaction (HER) with anodic small‐molecule oxidation reactions, have been proposed, which can produce high‐purity H2 and value‐added products. This review aims to systematically summarize the recent research on OER‐alternative reactions at the anode for energy‐efficient water splitting. The state‐of‐the art electrocatalysts for OER‐alternative reactions are first presented. The electrolysis performance in hybrid electrolysis regarding the conversion rate, selectivity, yield, and corresponding Faraday efficiency of anodic value‐added products is then evaluated. Finally, the challenges and perspectives are discussed and it is suggested to develop energy‐efficient and economically viable hybrid electrolysis systems.

3D interconnected MnMoO 4 nanosheet arrays with abundant open spaces and ordered arrangements deposited on nickel foam (NF@MnMoO 4 ) are fabricated by a mild one-step hydrothermal method. As an integrated binder-free electrode for supercapacitors, the optimized NF@MnMoO 4 electrode exhibits a superhigh specific capacitance of 4609 F g −1 (640 mAh g −1 ) at a current density of 1 A g −1 , remarkable rate capability (2800 F g −1 (388.89 mAh g −1 ) even at a current density as high as 20 A g −1 ), and outstanding cycling stability (92.4% of the initial specific capacitance after 20,000 cycles). The fabricated NF@MnMoO 4 //AC asymmetric supercapacitors (ASCs) with excellent cycling performance and high Coulombic efficiency achieve an ultrahigh energy density of 107.38 Wh kg −1 at a power density of 801.34 W kg −1 (72.18 Wh kg −1 at a power density of 3987.85 W kg −1 ). As the practical application, the self-charging power packs of commercial solar cells and NF@MnMoO 4 //AC ASCs are demonstrated to power an LED without extra recharging by other devices, indicating their promising applications in self-power energy-harvesting storage systems.

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N-Doped amber necklace-like structured MoS2@carbon nanofibers (ANL MoS2@CNFs) were fabricated via the confined growth, constructing a hierarchical structure with 2D nanosheets, yolk–shell structures, 1D nanofibers, and 3D cross-linked networks.