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Zn metal anode suffers from dendrite issues and passive byproducts, which severely plagues the practical application of aqueous Zn metal batteries. Herein, a polyzwitterionic cross-linked double network hydrogel electrolyte composed of physical crosslinking (hyaluronic acid) and chemical crosslinking (synthetic zwitterionic monomer copolymerized with acrylamide) is introduced to overcome these obstacles. On the one hand, highly hydrophilic physical network provides an energy dissipation channel to buffer stress and builds a H2O-poor interface to avoid side reactions. On the other hand, the charged groups (sulfonic and imidazolyl) in chemical crosslinking structure build anion/cation transport channels to boost ions' kinetics migration and regulate the typical solvent structure [Zn(H2O)6]2+ to R-SO3− [Zn(H2O)4]2+, with uniform electric field distribution and significant resistance to dendrites and parasitic reactions. Based on the above functions, the symmetric zinc cell exhibits superior cycle stability for more than 420 h at a high current density of 5 mA·cm−2, and Zn∥MnO2 full cell has a reversible specific capacity of 150 mAh·g−1 after 1000 cycles at 2 C with this hydrogel electrolyte. Furthermore, the pouch cell delivers impressive flexibility and cyclability for energy-storage applications. [ABSTRACT FROM AUTHOR]

Efficient and selective extraction of uranium (U(VI)) from seawater is essential for sustainable nuclear power production. This study reports a novel adsorbent zeolitic imidazolate framework (ZIF)-67@SiO2-A/polyacrylamide (PAM) which was synthesized by grafting the core–shell metal–organic frameworks (MOFs)-based nanostructures coated with the 3-aminopropyl triethoxysilane (APTES) functionalized SiO2 (SiO2-A) onto PAM hydrogel. The SiO2 shell was grown on the surface of MOF, which improved the acid-base resistance of MOF. The introduction of ZIF-67@SiO2-A enhances the specific surface area and adsorption efficiency of the PAM. The ZIF-67@SiO2-A/PAM shows remarkable adsorption capacity, fast adsorption kinetics, and good reusability for uranium. It has excellent adsorption property (6.33 mg·g−1, 30 d) in natural seawater. The X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FTIR), energy dispersive spectroscopy (EDS) mappings, and density functional theory reveal that the coordination by N and O in ZIF-67@SiO2-A/PAM with uranium is the main mechanism of uranium adsorption. Thus, ZIF-67@SiO2-A/PAM has great potential to capture uranium from natural seawater. [ABSTRACT FROM AUTHOR]

Conductive hydrogels are gaining significant attention as promising candidates for the fabrication materials for flexible electronics. Nevertheless, improving the tensile properties, hysteresis, durability, adhesion, and electrochemical properties of these hydrogels remains challenging. This work reports the development of a novel semi‐interpenetrating network poly(ionic liquid) hydrogel named PATV, via the in situ polymerization of acrylamide, N‐[Tris(hydroxymethyl)methyl] acrylamide, and 1‐vinyl‐3‐butylimidazolium tetrafluoroborate. The density functional theory calculations reveal that the poly(ionic liquid) in the hydrogel network acts as physical cross–linking points to construct hydrogen‐bond networks. Furthermore, the hydrogen‐bond networks dissipate energy efficiently and quickly, and thus stress concentration and hysteresis are avoided. The prepared hydrogel has a low hysteresis (9%), high tensile properties (900%), fast response (180 ms), high sensitivity (gauge factor = 10.4, pressure sensitivity = 0.14 kPa−1), and wide sensing range (tensile range: 1–600%, compression range: 0.1–20 kPa). A multifunctional sensor designed based on the designed hydrogel enables real‐time, rapid, and stable response‐ability for the detection of human movement, facial expression recognition, pronunciation, pulse, handwriting, and Morse code encryption. Furthermore, the assembled triboelectric nanogenerator displays an excellent energy harvesting capability, thus highlighting its potential application in self‐powered flexible wearable electronic devices. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOF)-polymer hybrid hydrogel solves the processable forming of MOF powder and energy consumption of uranium extraction. However, the hybrid hydrogel by conventional synthesis methods inevitably lead to MOF agglomeration, poor filler-polymer interfacial compatibility and slowly adsorption. Herein, we designed that ZIF-67 was implanted into the carboxymethyl cellulose/polyacrylamide (CMC/PAM) by network-repairing strategy. The carboxyl and amino groups on the surface of CMC/PAM drive the uniform growth of ZIF-67 inside the CMC/PAM, which form an array of oriented and penetrating microchannels through coordination bonds. Our strategy eliminate the ZIF-67 agglomeration, increase the interfacial compatibility between MOF and polymer. The method also improve the free and fast diffusion of uranium in CMC/PAM/ZIF-67 hydrogel. According to the experimental, these enhancements synergistically enabled the CMC/PAM/ZIF-67 have a maximum adsorption capacity of 952 mg g−1. The adsorption process of CMC/PAM/ZIF-67 fits well with pseudo-second-order model and Langmuir isotherm. Meanwhile, the CMC/PAM/ZIF-67 maintain a high removal rate (87.3 %) and chemical stability even during ten adsorption-desorption cycles. It is worth noting that the adsorption amount of CMC/PAM/ZIF-67 in real seawater is 9.95 mg g−1 after 20 days, which is an ideal candidate adsorbent for uranium extraction from seawater. • The CMC/PAM/ZIF-67 aerogel is successfully designed via network-repairing strategy. • The CMC/PAM/ZIF-67 aerogel has a maximum adsorption capacity of 952 mg g−1 at pH = 5. • The adsorption capacity of CMC/PAM/ZIF-67 aerogel in real seawater is 9.95 mg g−1 after 20 days. [ABSTRACT FROM AUTHOR]

[Display omitted] • Self-adhesive, self-healing and multimodal sensing organohydrogel was prepared. • Environmental stability of organohydrogel is enhanced by glycerol and PA. • The organohydrogel shows wide humidity response and temperature detection range. • The organohydrogel displays reliable strain sensing ability in a wide strain range. Conductive hydrogel (CH) has drawn widespread interest in flexible electronics, human–computer interaction, and electronic skins (e-skins). However, it is challenging to integrate satisfactory self-adhesion, self-healing, environmental stability, and multi-stimulus response into a single CH system. Herein, a conductive nanocomposite organohydrogel with the above characteristics is well-designed and developed via incorporating carboxylic cellulose nanofibers-carrying carboxylic carbon nanotubes (C-CNTs) and phytic acid (PA) into polyacrylamide network through free-radical polymerization plus glycerol solvent displacement strategy, aiming for a high-performance multimodal sensing platform. Here, the coupling of C-CNTs and ionization of PA contributes a favorable conductivity, and the coexistence of glycerol and PA is beneficial for the formation of amounts of hydrogen bonds that endow the organohydrogel with outstanding stretchability, self-healing, and favorable adhesion in a wide temperature range of −30 to 60 °C. Besides, the resultant organohydrogel can effectively detect multiple external stimuli, manifesting high strain sensitivity over a broad strain range (0–1566 %), good humidity detectability at 0–85 % RH, and reliable thermosensation capability over a wide temperature window (−30 to 60 °C). Significantly, the application of the organohydrogel as e-skins are conducted to detect full-range human activity movements even in the extreme environments, identify hand gestures, and recognize the spatial distribution of humidity in noncontact sensing. All these indicate the preponderance of our organohydrogel in the fields of flexible smart electronics. [ABSTRACT FROM AUTHOR]