Search

Conductive hydrogels with tunable multifunctionality show great potential in wearable smart devices. In this work, inspired by the nano-structured architecture strategy and natural mussel adhesive mechanism, a conductive hydrogel (AgPMP hydrogel) was fabricated through facile direct in situ polymerization. Silver nanowires (Ag NWs) and polydopamine (PDA) chains were integrated into the poly(N-isopropylacrylamide-co-acrylamide) (P(NIPAM-co-AM)) gel matrix, with activated PNIPAM microgels (MGs) serving as nano-crosslinkers. The overall internal structure of the hydrogel presented a heterogeneous cross-linked mesh-like structure with numerous irregular wrinkles. The AgPMP hydrogel demonstrated significantly enhanced mechanical strength, achieving a remarkable stretchability of 1140% attributed to the nano-microstructured architecture built using AM-based networks, nano-crosslinkers and Ag NWs. Moreover, due to the synergistic effect of PDA and Ag NWs, the hydrogel exhibited impressive photothermal antibacterial activity. Meanwhile, in the presence of abundant active catechol groups, this hydrogel possessed adequate tissue-adhesive and self-healing abilities as well as good antioxidant properties. Notably, the AgPMP hydrogel exhibited outstanding strain-sensitive conductivity. The resultant strain sensor showed high sensitivity with a gauge factor (GF) of up to 8.35 at a strain of 250%. The stable response signals during continuous and gradual cycling proved its electrical durability and stability. Combined with the great merits of the above performance, this sensor holds great promise for detecting human movements. The relative resistance change ranged from 16% to 64% as the finger bending angle changed from 30° to 90°. Thanks to its simple fabrication process, this multifunctional conductive hydrogel is expected to have widespread potential applications in tissue engineering, soft electronic skin and human-health monitoring. [ABSTRACT FROM AUTHOR]

Perovskite nanocrystals are embedded into metal–organic frameworks (MOFs) to create composites with high light absorption coefficients, tunable electronic properties, high specific surface area, and metal atom tunability for enhanced photocatalytic carban dioxide (CO2) reduction. However, existing perovskite‐MOF structures with a large particle size are achieved based on Pb source adsorption into the pores of MOFs, which can significantly break down the porous structure, thereby resulting in a decreased specific surface area and impacting CO2 adsorption. Herein, a novel perovskite‐MOF structure based on the synthesis of bimetallic Pb‐containing MOFs and post‐processing to convert Pb to CsPbBr3 nanocrystals (NCs) is proposed. It is discovered that the additional Pb is not introduced by adsorption, but instead engages in coordination and generates Pb‐N. The produced ZIF‐8@CsPbBr3 NCs are ≈40 nm and have an ultra‐high specific surface area of 1325.08 m2g−1, and excellent photovoltaic characteristics, which are beneficial for photocatalytic CO2 reduction. The electronic conversion rate of composites is 450 mol g−1h−1, which is more than three times that of pure perovskites. Additionally, the superior reduction capacity is sustained after undergoing four cycles. Density Functional Thoery (DFT) simulations are used to explore the 3D charge density at the ZIF‐8@CsPbBr3 NCs interface to better understand the electrical structure. [ABSTRACT FROM AUTHOR]

Utilizing plastic wastes as linker sources for metal–organic framework (MOF) synthesis is a green and sustainable methodology for the chemical upcycling of plastics. However, improving the depolymerization efficiency of polymers and avoiding highly corrosive solvents during the purification of the products remain significant challenges. Herein, we propose an approach to efficiently hydrolyze practical poly(ethylene terephthalate) (PET) wastes using aqueous dispersions of ultrasmall ZnO (6 nm) nanoparticles as the catalysts and subsequently synthesize five typical nano-MOFs by one-pot and two-pot strategies. The neutral hydrolysis of PET is greatly accelerated, with PET being completely depolymerized at 200 °C in 60 min with a terephthalic acid yield of 95.6%. The PET-derived MOF nanoparticles present high BET surface areas that are higher than or close to those of congeneric MOFs synthesized from petroleum-based and highly purified ligands. As a water absorbent, the two-pot MIL-101(Cr) exhibits high thermal stability with a water uptake capacity of 1327.3 mg g−1. For photocatalytic degradation of antibiotic pollutants, MIL-53(Al, Fe) samples derived from PET textiles show a high tetracycline removal efficiency of over 90% within 60 min without additives in an aqueous system, outperforming most of the conventionally prepared MOF catalysts. This approach disposes of discarded plastics in an eco-friendly way and produces value-added materials with excellent catalysis and adsorption properties. [ABSTRACT FROM AUTHOR]