Fast water transport reversible CNT/PVA hybrid hydrogels with highly environmental tolerance for multifunctional sport headband

The water transport in hydrogel has been proven to be critical for water evaporation, water treatment and moisture-wicking. However, confined with the regulation of pore structure, challenges remain in constructing fast water transport channels especially in harsh water environment. Herein, we demonstrate a simple strategy for fabrication of fast water transport carbon nanotube/poly (vinyl alcohol) (CNT/PVA) hydrogels via efficiently interior infiltration and decoration of CNT cellular structures with PVA. The CNT/PVA double-network structures favor the generation of hierarchical micro/nanochannels and strong capillary forces, leading to water transport throughout the hydrogel up to ~15.8 g g−1s−1, recorded highest among reported hydrogels. The as-formed elastic hybrid hydrogels present a reversible absorbing/shrinking behavior, an excellent capacity in water absorption (216 g g−1), and high adaptability in salty water, acid and alkaline solutions as well as boiling water. Moreover, a multifunctional sport headband has been designed based on fast water transport and conductive framework, which can perform fantabulous moisture-wicking and health monitor. This work proposes a new route for developing fast water transport hydrogels towards versatile flexible electronic devices and multifunctional sport management systems.