2D MXenes Embedded Perovskite Hydrogels for Efficient and Stable Solar Evaporation

Solar evaporation is a facile and promising technology to efficiently utilize renewable energy for freshwater production and seawater desalination. Here, the fabrication of self-regenerating hydrogel composed of 2D-MXenes nanosheets embedded in perovskite La Sr-0.6 Co-0.4 Fe-0.2 O-0.8(3-)& delta; (LSCF)/polyvinyl alcohol hydrogels for efficient solar-driven evaporation and seawater desalination is reported. The mixed dimensional LSCF/Ti3C2 composite features a localized surface plasmonic resonance effect in the polymeric network of polyvinyl alcohol endows excellent evaporation rates (1.98 kg m(-2) h(-1)) under 1 k Wm(-2) or one sun solar irradiation ascribed by hydrophilicity and broadband solar absorption (96%). Furthermore, the long-term performance reveals smooth mass change (13.33 kg m(-2)) during 8 h under one sun. The composite hydrogel prompts the dilution of concentrated brines and redissolves it back to water (1.2 g NaCl/270 min) without impeding the evaporation rate without any salt-accumulation. The present research offers a substantial opportunity for solar-driven evaporation without any salt accumulation in real-life applications.

Automated summary

A self-regenerating hydrogel composed of 2D-MXenes nanosheets embedded in perovskite La Sr-0.6 Co-0.4 Fe-0.2 O-0.8(3-)& delta; (LSCF)/polyvinyl alcohol hydrogels has been developed for efficient solar-driven evaporation and seawater desalination. The composite hydrogel exhibits excellent evaporation rates and broadband solar absorption, and can dilute concentrated brines without impeding the evaporation rate or salt accumulation.