Liquid metal assisted fabrication of MXene-based films: Toward superior electromagnetic interference shielding and thermal management.

The development of thin and flexible films that possess both electromagnetic interference (EMI) shielding and thermal management capabilities has always been an intriguing pursuit, but itisnevertheless a crucialproblemtoaddress. Inspired by the deformability of liquid metal (LM) and film forming capacity of MXene, here we present a series of ternary compositing films prepared via cellulose nanofiber (CNF) assisted vacuum filtration technology. Originating from the highly conductive LM/MXene network, the MLMC film presents a maximum EMI shielding effectiness (EMI SE) of 78 dB at a tiny thickness of 45 µm, together with a high specific EMI SE of 3046 dB mm-1. Meanwhile, these compositing films also deliver excellent flexibility and mechanical reliability, showing no obvious decline in EMI shielding performance even after 1000 bending and 500 folding cycles, respectively. Moreover, notable anisotropic thermal conductive property was successfully achieved, allowing for a highly desirable in-plane thermal conductivity of 7.8 W m-1 K-1. This accomplishment also yielded an exceptional electro-thermal conversion capacity, enabling efficient low-voltage (3 V) heating capabilities. These captivating features are expected to greatly drive the widespread adoption of LM-based films in future flexible electronic and wearable technologies.

Acidic and alkaline gas sensitive and self-healing chitosan aerogel based on electrostatic interaction.

Gas pollution is a serious problem. More attention has been paid to the detection and monitoring of toxic and harmful gases, and it is urgently needed for a sensor that could simultaneously identify and distinguish between acid and base gases. Based on the electrostatic interaction resulting from amidogen of chitosan (CS) and carboxylic groups of itaconic acid (IA), we successfully prepared a series of biomass aerogels (CS-IA aerogels) that could respond to acidic and alkaline gases with different concentrations. The acidic and alkaline gases could be easily detected and distinguished by changing the content of IA in CS-IA aerogels. Moreover, the electrostatic interactions could also endowed CS-IA aerogels with self-healing ability in the breaks at room temperature. After self-healing, CS-IA aerogels still sensitively answered to acidic and alkaline gases. CS-IA aerogels with sensitivity to acid-base gas and self-healing performance has been suggested to be promising candidates as application of multi-functional aerogels.

Facile fabrication of wood-inspired aerogel from chitosan for efficient removal of oil from Water.

Aerogels that derived from biomass have long been attractive as absorbents for oil clean-up. However, it remains a significant challenge to prepare fully bio-based oil absorbents that combines fast oil/water separation capacity, adequate mechanical robustness and easy recyclability through green and facile strategy. Inspired by the fascinating structure of wood, here we report a highly porous and anisotropic bio-based aerogel by taking advantage of the directional freezing technology, followed by a freeze-drying and silylation process. Due to the directional growth of ice crystals along the vertical direction, a special spring like morphology was obtained, which is mainly composed of well aligned low-tortuosity channels that seamlessly connected to bottom layer. Superior mechanical properties that allow for high mechanical compressing and fast elastic recovery were consequently acquired. Moreover, the silylated CS aerogel displays a rather high oil absorption capacity of 63 g g-1, together with excellent recyclability via simple hand squeezing. By virtue of such hierarchical morphology, a device that could continuously separate oil from water was successfully designed. Given the natural abundance of raw material as well as the easy processability, this work would lay solid foundation for further fabrication of bio-based oil absorbents toward low-cost, high-performance and large-scale commodities.