An all-weather steam generation system is achieved based on the alternative photo-thermal and electro-thermal conversion of crosslinked MXene aerogels.

A phase change mediated mechanically transformative dynamic gel enables dramatic stiffness change under a heat stimulus for intelligent control of versatile devices.

Acute kidney injury (AKI), as a common oxidative stress-related renal disease, causes high mortality in clinics annually, and many other clinical diseases, including the pandemic COVID-19, have a high potential to cause AKI, yet only rehydration, renal dialysis, and other supportive therapies are available for AKI in the clinics. Nanotechnology-mediated antioxidant therapy represents a promising therapeutic strategy for AKI treatment. However, current enzyme-mimicking nanoantioxidants show poor biocompatibility and biodegradability, as well as non-specific ROS level regulation, further potentially causing deleterious adverse effects. Herein, the authors report a novel non-enzymatic antioxidant strategy based on ultrathin Ti 3 C 2 -PVP nanosheets (TPNS) with excellent biocompatibility and great chemical reactivity toward multiple ROS for AKI treatment. These TPNS nanosheets exhibit enzyme/ROS-triggered biodegradability and broad-spectrum ROS scavenging ability through the readily occurring redox reaction between Ti 3 C 2 and various ROS, as verified by theoretical calculations. Furthermore, both in vivo and in vitro experiments demonstrate that TPNS can serve as efficient antioxidant platforms to scavenge the overexpressed ROS and subsequently suppress oxidative stress-induced inflammatory response through inhibition of NF-B signal pathway for AKI treatment. This study highlights a new type of therapeutic agent, that is, the redox-mediated non-enzymatic antioxidant MXene nanoplatforms in treatment of AKI and other ROS-associated diseases.

Solid–liquid phase change materials (PCMs) are widely used in heat management. However, the requirement of no leakage of solid–liquid PCMs during phase transition and suitable deformability at evaluated temperature are contradictory when PCMs are used as thermal interface materials (TIMs). Vitrimer, a kind of material that combines with the advantages of both thermoplastics and thermosets, may be a solution. Herein, polyethylene wax vitrimer (PEWV) is prepared through the dioxaborolane exchange reaction for TIMs with leakage-proof and high-energy-storage ability. Microphase separation occurs between highly cross-linked skeleton and slightly cross-linked chains, which solves the leakage problem of polyethylene wax. Simultaneously, PEWV can achieve a high latent heat storage capacity of about 121.0 J g–1, about 74% of that of PEW, owing to the negligible effect of dynamic cross-linking on the crystallization of PEW. Meanwhile, PEWV can be plastically deformed and tightly adhered to the rigid surface under a slight external force at the phase change temperature, filling the gap at macro- and microscales for improving the heat transfer efficiency. The composites of PEWV and thermal conductive filler show more excellent performance as TIMs than commercial thermal conductive pads. PEWV with no leakage, excellent plasticity, and high latent heat storage capacity provides great application potential in heat storage and thermal interface management.

Because of its rather low melt strength, polylactide (PLA) has yet to fulfill its promise as advanced biobased and biodegradable foams to replace fossil-based polymer foams. In this work, PLA vitrimers were prepared by two-step reactive processing from commercial PLA thermoplastics, glycerol, and diphenylmethane diisocyanate (MDI) using Zn­(II)-catalyzed addition and transesterification chemistry. The transesterification reaction of PLA and glycerol occurs with zinc acetate as the catalyst, and chain scission will take place due to the alcoholysis of the PLA chains by the free hydroxyl groups from the glycerol. Long-chain PLA with hydroxyl groups can be obtained and then cross-linked with MDI. Rheological analysis shows that the formed cross-linked network can significantly improve melt strength and promote strain hardening under extensional flow. PLA vitrimers still maintain the ability of thermoplastic processing via extrusion and compression. The enhanced melt strength and the rearrangement of network topology facilitate the foaming processing. An expansion ratio as large as 49.2-fold and microcellular foam with a uniform cell morphology can be obtained for PLA vitrimers with a gel fraction of 51.8% through a supercritical carbon dioxide foaming technique. This work provides a new way with the scale-up possibility to enhance the melt strength of PLA, and the broadened range of PLA applicability brought by PLA vitrimers is truly valuable in terms of the realization of a sustainable society.