Carbonized CMPs Hollow Microspheres-Based Hydrogel Composite Membranes with a Hierarchical Architecture for Efficient Solar-Driven Interfacial Evaporation

Solar-driven interfacial evaporation (SDIE) with excellentphotothermalconversion efficiency is emerging as one of the frontier technologiesfor freshwater production. In this work, novel carbonized conjugatemicroporous polymers (CCMPs) hollow microspheres-based composite hydrogelmembranes (CCMPsHM-CHM) for efficient SDIE are reported. The precursor,CMPs hollow microspheres (CMPsHM), is synthesized by an insitu Sonogashira-Hagihara cross-coupling reaction using ahard template method. The as-synthesized CCMPsHM-CHM exhibit significantlyexcellent properties, i.e., 3D hierarchical architecture(from micropore to macropore), superior solar light absorption (morethan 89%), better thermal insulation (thermal conductivity as lowas 0.32-0.42 W m(-1)K(-1) inthe wet state), superhydrophilic wettability with a water contactangle (WCA) of 0 & DEG;, superior solar efficiency (up to 89-91%),a high evaporation rate of 1.48-1.51 kg m(-2) h(-1) under 1 sun irradiation, and excellent stabilitywhich maintains an evaporation rate of more than 80% after 10 cyclesand over 83% evaporation efficiency in highly concentrated brine.In this case, the removal rate of metal ions in seawater is more than99%, which is much lower than the ion concentration standard for drinkingwater set by the World Health Organization (WHO) and the United StatesEnvironmental Protection Agency (USEPA). Taking advantage of its simpleand scalable manufacture, our CCMPsHM-CHM may have great potentialas advanced membranes for various applications for efficient SDIEin different environments.

Automated summary

This study reports a novel carbonized conjugate microporous polymers (CCMPs) hollow microspheres-based composite hydrogel membranes (CCMPsHM-CHM) for efficient solar-driven interfacial evaporation (SDIE). The CCMPsHM-CHM exhibit excellent properties including 3D hierarchical architecture, superior solar light absorption, better thermal insulation, superhydrophilic wettability, high evaporation rate, and excellent stability. It has great potential for efficient SDIE in different environments and can effectively remove metal ions in seawater.