High strength, toughness, and conductivity are among the most sought‐after properties of flexible electronics. However, existing engineering materials find it difficult to achieve both excellent mechanical properties and high conductivity. To address this challenge, this study proposes a facile yet versatile strategy for preparing super‐tough conductive organo‐hydrogels via freeze‐casting assisted solution substitution (FASS). This FASS strategy enables the formation of organo‐hydrogels in one step with exquisite hierarchical anisotropic structures coupled with synergistic strengthening and toughening effects across multiple length scales. As an exemplary material, the prepared polyvinyl alcohol (PVA) organo‐hydrogel with solvent content up to 87 wt% exhibits a combination of high strength (6.5 MPa), high stretchability (1710% in strain), ultra‐high toughness (58.9 MJ m−3), as well as high ionic conductivity up to 6.5 S m−1 with excellent strain sensitivity. The exceptional combination of mechanical properties and conductivity makes the PVA organo‐hydrogel a promising flexible electronics material. In addition, the FASS strategy can also endow hydrogels with multi‐functions, including thermo‐healability, freezing tolerance and shape recoverability, and can be applied to various hydrogel materials, such as carboxymethyl cellulose, sodium alginate, and chitosan. Hence, this work provides an all‐around solution for preparing advanced strong and tough conductive soft materials for a multitude of applications.

Four‐dimensional (4D) printing enables programmable, predictable, and precise shape change of responsive materials to achieve desirable behaviors beyond conventional three‐dimensional (3D) printing. However, applying 4D printing to ceramics remains challenging due to their intrinsic brittleness and inadequate stimuli‐responsive ability. Here, this work proposes a conceptional combination of bioinspired microstructure design and a programmable prestrain approach for 4D printing of nanoceramics. To overcome the flexibility limitation, the bioinspired concentric cylinder structure in the struts of 3D printed lattices are replicated to develop origami nanoceramic composites with high inorganic content (95 wt%). Furthermore, 4D printing is achieved by applying a programmed prestrain to the printed lattices, enabling the desired deformation when the prestrain is released. Due to the bioinspired concentric cylinder microstructures, the printed flexible nanoceramic composites exhibit superior mechanical performance and anisotropic thermal management capability. Further, by introducing oxygen vacancies to the ceramic nanosheets, conductive nanoceramic composites are prepared with a unique sensing capability for various sensing applications. Hence, this research breaks through the limitation of ceramics in 4D printing and achieves high‐performance shape morphing materials for applications under extreme conditions, such as space exploration and high‐temperature systems.

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Graphene aerogels have gained considerable attention due to their unique physical properties, but their poor mechanical properties and lack of functionality have hindered their advanced applications. In this study, we propose a blend-spinning-assisted freeze-casting (BSFC) strategy to incorporate particle-modified carbon fibers into graphene aerogels for mechanical strengthening and functional enhancement. This method offers a great deal of freedom in the creation of customizable multimaterial, multiscale structural graphene aerogels. For example, we fabricated silicon carbide particle modified carbon fiber reinforced graphene (SiC/CF-GA) aerogels. The resulting aerogels display excellent properties such as being ultralightweight and highly resilient and having fatigue compression resistance (1000 cycles at 50% strain). Meanwhile, enhanced resilience inspired the effective strain-sensing capabilities of SiC/CF-GA aerogels with a sensitivity of 13.8 kPa–1. The adjustable dielectric properties due to SiC particle incorporation endow the SiC/CF-GA aerogel with a broad-band (8.0 GHz) effective electromagnetic wave attenuation performance. Besides, different particles could be incorporated into graphene aerogels via the BSFC strategy, allowing for customizable designs. Moreover, multifunctionalities were demonstrated by the modified aerogels, including noise absorption, thermal insulation, fire resistance, and waterproofing, further diversifying their practicality. Hence, the BSFC strategy provides a customized solution for fabricating modified graphene aerogels for advanced functional applications.

Conductive hydrogels possess remarkable potential for applications in soft electronics and robotics, owing to their unique combination of high electrical conductivity, stretchability, and impressive self-healing capabilities. Nonetheless, the limited strength and toughness of these hydrogels have traditionally impeded their practical implementation. Inspired by the hierarchical architecture of high-performance biological composites found in Nature, this study successfully fabricates a novel type of strong and tough conductive hydrogel through self-assembly-induced bridge crosslinking of MgB2 nanosheets and polyvinyl alcohol (PVA) hydrogels. By combining the micro- to nano-level hierarchical lamellar structures of PVA hydrogels with the robust molecular-level B-O covalent bonds, the resulting conductive hydrogel exhibits an exceptional strength of 8.58 to 32.7 MPa and a high toughness of 27.56 to 123.3 MJ/m3. Moreover, the hydrogel demonstrates exceptional sensitivity (with a response/relaxation time of 20ms and a detection lower limit of ~ 1Pa) under external deformation, thanks to its nanoscale MgB2 nanosheets/PVA lamellar structure and extremely low compressive modulus. These unique characteristics enable the conductive hydrogel to exhibit superior performance in advanced soft sensing applications, particularly in non-contact speaking detection. This study represents a major breakthrough, introducing a new class of conductive hydrogel that integrates exceptional strength, toughness, and sensitivity, thereby opening up exciting possibilities for the development of high-performance conductive hydrogels.