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The development of modern electronics has raised great demand for multifunctional materials to protect electronic instruments against electromagnetic interference (EMI) radiation and ice accretion in cold weather. However, it is still a great challenge to prepare high-performance multifunctional films with excellent flexibilty, mechanical strength, and durability. Here, we propose a layer-by-layer assembly of cellulose nanofiber (CNF)/Ti3C2Tx nanocomposites (TM) on a bacterial cellulose (BC) substrate via repeated spray coating. CNFs are hybridized with Ti3C2Tx nanoflakes to improve the mechanical properties of the functional coating layer and its adhesion with the BC substrate. The densely packed hierarchical structure and strong interfacial interactions endows the TM/BC films with good flexibility, ultrahigh mechanical strength (>250 MPa), and desirable toughness (>20 MJ cm-3). Furthermore, benefiting from the densely packed hierarchical structure, the resultant TM/BC films present outstanding EMI shielding effictiveness of 60 dB and efficient electro-/photothermal heating performance. Silicone encapsulation further imparts high hydrophobicity and exceptional durability against solutions and deformations to the multifunctional films. Impressively, the silicone-coated TM/BC film (Si-TM/BC) exhibits desirable low voltage-driven Joule heating and excellent photoresponsive heating performance, which demonstrates great feasibility for efficient thermal deicing under actual conditions. Therefore, we believe that the Si-TM/BC film with excellent mechanical properties and durability holds great promise for the practical applications of EMI shielding and ice accretion elimination.

Electromagnetic interference (EMI) and radiation of electronic devices are ubiquitous, which are potentially hazardous to the normal operation of electronic equipment and human health. MXenes are extremely attractive in the preparation of EMI shielding materials due to their excellent metallic conductivity and tunable surface chemistry. Herein, by virtue of the designed nanostructure and regulation of interface interactions, we fabricated flexible Fe3O4@Ti3C2Tx MXene/3,4-dihydroxyphenylacetic acid (DOPAC)-epoxidized natural rubber (ENR) elastomers (FMDE) with 3D segregated interconnected structures. The elaborately designed metal-ligand coordination crosslinking between Fe3O4 nanoparticles and DOPAC ligand molecules provides strong interfacial interactions, resulting in significantly reinforced mechanical properties. Compared with Ti3C2Tx/ENR elastomers, the maximum tensile strength and toughness of FMDE are elevadted by ~306% and 475%, respectively. Moreover, the 3D segregated conductive network constructed by Fe3O4@Ti3C2Tx nanoflakes resulted from volume exclusion effect of ENR latex and the introduction of magnetic Fe3O4 nanoparticles with enhanced electromagnetic wave absorption greatly improved the EMI shielding performance of FMDE, exhibiting an excellent EMI shielding effectiveness of up to 58 dB in the X band (8.2–12.4 GHz) and stable EMI shielding capability during repeated deformations. This work provides a promising strategy for the design and manufacture of novel flexible EMI shielding materials.

Soft actuation materials are highly desirable in flexible electronics, soft robotics, etc. However, traditional bilayered actuators usually suffer from poor mechanical properties as well as deterio...

Progress toward the integration of electronic sensors with a signal processing system is important for artificial intelligent and smart robotics. It demands mechanically robust, highly sensitive, and self-healable sensing materials which could generate discernible electric variations responding to external stimuli. Here, inspired by the supramolecular interactions of amino acid residues in proteins, we report a self-healable nanostructured Ti3C2MXenes/rubber-based supramolecular elastomer (NMSE) for intelligent sensing. MXene nanoflakes modified with serine through an esterification reaction assemble with an elastomer matrix, constructing delicate dynamic supramolecular hydrogen bonding interfaces. NMSE features desirable recovered toughness (12.34 MJ/m3) and excellent self-healing performance (∼100%) at room temperature. The NMSE-based sensor with high gauge factor (107.43), low strain detection limit (0.1%), and fast responding time (50 ms) can precisely detect subtle human motions (including speech, facial expression, pulse, and heartbeat) and moisture variations even after cut/healing processes. Moreover, NMSE-based sensors integrated with a complete signal process system show great feasibility for speech-controlled motions, which demonstrates promising potential in future wearable electronics and soft intelligent robotics.

The development of modern electronics has raised great demand for multifunctional materials to protect electronic instruments against electromagnetic interference (EMI) radiation and ice accretion in cold weather. However, it is still a great challenge to prepare high-performance multifunctional films with excellent flexibilty, mechanical strength, and durability. Here, we propose a layer-by-layer assembly of cellulose nanofiber (CNF)/Ti

Soft actuation materials are highly desirable in flexible electronics, soft robotics

Progress toward the integration of electronic sensors with a signal processing system is important for artificial intelligent and smart robotics. It demands mechanically robust, highly sensitive, and self-healable sensing materials which could generate discernible electric variations responding to external stimuli. Here, inspired by the supramolecular interactions of amino acid residues in proteins, we report a self-healable nanostructured Ti

Stereolithographic 3D printing has been increasingly applied in the rapid fabrication of gels with specially-designed 3D structures. Herein, MXene (Ti3C2Tx) is reported for the first time as a versatile photo blocker for a photo-curable aqueous ink for a newly developed stereolithography technology (Continuous Liquid Interface Production, CLIP) to fabricate hydrogels with delicate geometries. As an effective photo blocker, the MXene nanosheets can significantly suppress the light scatting in the hydrogel precursor ink during CLIP printing, giving rise to printing quality. Subsequent solvent exchange with glycerin produces an organogel, which shows excellent adhesive properties towards various surfaces, making it a promising adhesive sensor to detect different body movements. Meanwhile, the CLIP-printed organogel demonstrates promise in atmospheric water harvesting taking advantage of the natural hygroscopicity of organogel and excellent light-to-heat conversion performance with MXene nanosheets. Furthermore, the CLIP-printed hollow organogel shows higher efficiency benefiting from larger surface area of hollow organogel. The results of this work strongly suggest that MXene can serve as an effective multifunctional additive for CLIP inks, which may open up new opportunities for the 3D printing of various advanced devices.

As a class of promising 2D material, MXenes are widely applied to energy storage systems (ESSs) due to metallic conductivity and high electrochemical activities, but the restacking problem during electrode preparation restricts their electrochemical performances. Herein, polyaniline nanofibers (PANINFs) are used as conductive interlayer spacers to induce the self-assembly of MXene (Ti3C2Tx)-based electrode. The favored sandwiched porous structure is formed due to the electrostatic adsorption and hydrogen bond interaction between the positively charged PANINFs and the negatively charged Ti3C2Tx nanosheets, which provide abundant accessible sites and facilitate the diffusion of ions. As a result, the flexible freestanding Ti3C2Tx/PANINFs composite electrode exhibits high conductivity (1373.3 S cm–1) and excellent gravimetric capacitance of 645.7 F g–1. Due to the enhanced structural stability, it achieves impressive cycling stability of 98% capacitance retention after 5000 cycles, which is significantly improved from that of pristine Ti3C2Tx electrode (84.6%). This work provides a feasible strategy for the structure regulation and performance enhancement of MXene-based supercapacitors, which has great potential in energy storage systems.