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Solar-powered water purification is one of the promising choices for clean water production. However, it remains challenging to develop aerogel solar evaporators that simultaneously possess enhanced light-to-heat conversion, optimal thermal management, and salt crystal deposition inhibition. Herein, to address this challenge, we have developed a 3D chitosan-reduced graphene oxide/polypyrrole (CS-RGO/PPy) aerogel vaporizer with a vertical and radially aligned structure through a directional freezing process, inspired by the featured structure of conifers. The radially porous walls and vertically arranged channels within the 3D aerogel were able to facilitate high light absorption, localizing converted heat, rapid water transport, and self-salt discharge. Under 1 sun irradiation, the aerogel vaporizer displayed an improved light absorption characteristic of 95% and a high-rate evaporation (∼3.19 kg m–2 h–1) that achieved continuous freshwater from the saturated brine production without solid salt crystallization. Besides achieving seawater desalination, the obtained aerogel could purify organic wastewater and emulsions through solar distillation with high-rate continuous water production.

Conductive hydrogels have gained increasing attention in the field of wearable smart devices. However, it remains a big challenge to develop a multifunctionally conductive hydrogel in a rapid and facile way. Herein, a conductive tannic acid–iron/poly (acrylic acid) hydrogel was synthesized within 30 s at ambient temperature by the tannic acid–iron (TA@Fe3+)-mediated dynamic catalytic system. The TA@Fe3+ dynamic redox autocatalytic pair could efficiently activate the ammonium persulfate to initiate the free-radical polymerization, allowing the gelation to occur easily and rapidly. The resulting hydrogel exhibited enhanced stretchability (3560%), conductivity (33.58 S/m), and strain sensitivity (gauge factor = 2.11). When damaged, it could be self-healed through the dynamic and reversible coordination bonds between the Fe3+ and COO– groups in the hydrogel network. Interestingly, the resulting hydrogel could act as a strain sensor to monitor various human motions including the huge movement of deformations (knuckle, wrist) and subtle motions (smiling, breathing) in real time due to its enhanced self-adhesion, good conductivity, and improved strain sensitivity. Also, the obtained hydrogel exhibited efficient electromagnetic interference (EMI) shielding performance with an EMI shielding effectiveness value of 24.5 dB in the X-band (8.2–12.4 GHz). Additionally, it displayed antibacterial properties, with the help of the activity of TA.