Manufacturing robust MXene-based hydrogel-coated cotton fabric via electron-beam irradiation for efficient interfacial solar evaporation

Herein, a robust Ti3C2Tx MXene-based hydrogel-coated cotton fabrics (MHCFs) was facilely prepared by electron beam (E-beam) irradiation induced crosslinking under mild condition, which efficiently combined the outstanding light absorption and photothermal conversion performance of MXene with the excellent water transport capacity and good mechanical property of cotton fabrics (CFs). The novel MHCFs deservedly achieved not only high solar absorption, but also excellent water evaporation rate (1.65 kg m- 2h-1 under 1-sun irradiation), which breaks through the theoretical limit of planar evaporators (1.47 kg m- 2h-1). It also shows great stability and no salt accumulation in long-time continuous solar evaporation of 3.5 wt% NaCl solution, which remained its evaporation rate around 1.49 kg m- 2h-1 under 1-sun irradiation after 12 cycles. Moreover, the covalent crosslinking among the Ti3C2Tx MXene sheets, PVA and cellulose of CF induced by E-beam irradiation also endowed the MHCFs with good tolerance to acidic and ultrasonic treatments. In addition, the MHCFs were facilely assembled as a 3D evaporator with cylindrical structure, which not only exhibits 3.74 kg m- 2h-1 of water evaporation rate under 1-sun irradiation, but also achieves 2.46 kg m- 2h-1 of averaged rate from 3.5 wt% solution after 5 cycles of continuous long-time evaporation test. This study opens a pave to fabricate robust hydrogel-coated photothermal fabrics in continuous and large-scale manner, and expands the application of solar-driven interfacial evaporation (SDIE) to the seawater desalination, wastewater treatment and evaporative crystallization, and so on.