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Organophosphorus‐based chemical warfare agents (CWAs) are highly poisonous, and recent attacks using nerve agents have stimulated researchers to develop breakthrough materials for their fast degradation. Zr‐based materials have been identified as the most effective catalysts for breaking down CWAs, but in their powdered form, their practical application in personal protective equipment is limited. Herein, a surface‐confined strategy for the direct growth of vertically aligned zirconium hydroxide (Zr(OH)4) nanosheets with ultrathin and tortuous structures on nanofibers is reported. The freestanding Zr(OH)4 nanosheet‐assembled nanofibrous membranes (NANMs) show superior catalytic performance to degrade dimethyl methylphosphonate, a nerve agent simulant, with a half‐life of 4 min. In addition, intriguing membrane‐type NANMs feature integrated properties of exceptional breathability, prominent flexibility, and robust fatigue resistance over one million buckling loads. This facile strategy provides a novel route to manufacture new classes of nanosheet‐supported membranes for chemical‐protective materials, in particular for gas filters, protective suits, and clothing.

Chemical warfare agents (CWAs) pose huge threats to ecological environments, agriculture, and human health due to the turbulent international situation in contemporary society. Zirconium hydroxide (Zr(OH) 4 ) has captured the prime focus as an effective candidate for CWA decomposition but is often hindered by the isolated powder form. Here, we demonstrate a scalable three-dimensional space-confined synthetic strategy to fabricate nanoflake-engineered zirconic fibrous aerogels (NZFAs). Our strategy enables the stereoscopic Zr(OH) 4 nanoflakes vertically and evenly in situ grown on the interconnected fibrous framework, remarkably enlarging the surface area and providing rich active sites for CWA catalysis. The as-synthesized NZFAs exhibit intriguing properties of ultralow density (>0.37 mg cm −3 ), shape-memory behavior under 90% strain, and robust fatigue resistance over 10 6 compression cycles at 40% strain. Meanwhile, the high air permeability, prominent adsorptivity, and reusability make them state-of-the-art chemical protective materials. This work may provide an avenue for developing next-generation aerogel-based catalysts and beyond.

To date, the reckless use of deadly chemical warfare agents (CWAs) has posed serious risks to humanity, property, and ecological environment. Therefore, necessary materials able to rapidly adsorb and securely decompose these hazardous toxics are in urgent demand. Herein, three-dimensional (3D) reduced graphene oxide/Zr-doped TiO2 nanofibrous aerogels (RGO/ZT NAs) are synthesized by feasibly combining sol–gel electrospinning technology and a unidirectional freeze-drying approach. Benefiting from the synergetic coassembly of flexible ZT nanofibers and pliable RGO nanosheets, the hierarchically entangled fibrous frameworks feature ultralow density, superior elasticity, and robust fatigue resistance over 106 compressive cycles. In particular, the RGO incorporation is attributed to the achieved increased surface area, stronger light absorption, and decreased recombination of charge-carriers for photocatalysis. The highly porous 3D RGO/ZT NAs deliver enhanced photothermal catalytic activity for CWA degradation as well as excellent recyclability and good photostability. This work opens fresh horizons for developing advanced 3D aerogel-based photocatalysts in a controlled fashion.

Traditional oxide ceramics are inherently brittle and highly sensitive to defects, making them vulnerable to failure under external stress. As such, endowing these materials with high strength and high toughness simultaneously is crucial to improve their performance in most safety‐critical applications. Fibrillation of the ceramic materials and further refinement of the fiber diameter, as realized by electrospinning, are expected to achieve the transformation from brittleness to flexibility owing to the structural uniqueness. Currently, the synthesis of electrospun oxide ceramic nanofibers must rely on an organic polymer template to regulate the spinnability of the inorganic sol, whose thermal decomposition during ceramization will inevitably lead to pore defects, and seriously weaken the mechanical properties of the final nanofibers. Here, a self‐templated electrospinning strategy is proposed for the formation of oxide ceramic nanofibers without adding any organic polymer template. An example is given to show that individual silica nanofibers have an ideally homogeneous, dense, and defect‐free structure, with tensile strength as high as 1.41 GPa and toughness up to 34.29 MJ m−3, both of which are far superior to the counterparts prepared by polymer‐templated electrospinning. This work provides a new strategy to develop oxide ceramic materials that are strong and tough.

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