Perspective for removing volatile organic compounds during solar‐driven water evaporation toward water production

Abstract

Solar evaporation has attracted considerable interest to alleviate the shortage of water resources in the past few years. Lots of works have been done focusing on evaporation materials, rate, and efficiency, however, little attempts have been made to remove the harmful volatile organic compounds (VOCs), a kind of contamination that inevitably evaporate and condense alongside with water, which seriously affect the distilled water quality. This perspective puts forward some technical ideas utilizing chemical or physicochemical methods, aiming at the development of multifunctional composite materials, and forming an integrated evaporation system, which manage to remove VOCs in situ at the interface of photothermal evaporation.

A Light-Permeable Solar Evaporator with Three-Dimensional Photocatalytic Sites to Boost Volatile-Organic-Compound Rejection for Water Purification

“…Photocatalysis, is another solar-driven interfacial process that can inherently combine with the photothermal process and thus holds the potential to serve as a VOC-intercepting strategy for SIE. − Photocatalysis has the unique advantages of no requirement of continual addition of expensive oxidants compared with advanced oxidation methods , and being not easily saturated compared with adsorption technology , and thus is quite meaningful for sustainable operations. Nevertheless, photocatalysis generally occurs only at the light-available 2D top surface, which seriously limits the catalytic efficiency of materials.…”

Repurposing face mask waste to construct floating photothermal evaporator for autonomous solar ocean farming

“…Aside from the environmental concerns induced by disposable FM, water scarcity is another enormous challenge across the globe as the global demand of clean water keeps increasing dramatically 10 . Solar thermal desalination, which particularly occurs at the seawater/air interface by photothermally converting solar energy into steam generation, has drawn widespread attention as an emerging clean water production technology to mitigate water scarcity 11–17 . Solar absorbing materials positioning at the interface therefore play a critical role in the photothermal conversion process.…”

“…10 Solar thermal desalination, which particularly occurs at the seawater/ air interface by photothermally converting solar energy into steam generation, has drawn widespread attention as an emerging clean water production technology to mitigate water scarcity. [11][12][13][14][15][16][17] Solar absorbing materials positioning at the interface therefore play a critical role in the photothermal conversion process. To achieve high evaporation rate and solar utilization efficiency, an ideal solar evaporator should be capable of broadband light absorption in the range of 300-2500 nm while possessing a hierarchical and porous structure, of which the latter favors light trapping, capillary transportation and fast vapor release.…”

A polyaniline nanofiber array supported ultrathin polyamide membrane for solar-driven volatile organic compound removal

“…The key to efficient VOC removal during the solar-driven interfacial evaporation is designing a separation medium that allows water to evaporate through but intercepts VOCs. 21 Very recently, based on the solution–diffusion mechanism, a photothermal process has been designed to remove VOCs from water where either a polypyrrole membrane 20 or an alginate-based hydrogel 22 was used as the separation medium. In this process, the separation medium has different affinity for water or VOCs and the migration rate of water is usually higher than that of VOCs, so the removal of VOCs from water could be achieved.…”