Systematic Review of Material and Structural Design in Interfacial Solar Evaporators for Clean Water Production

Abstract

Rational and sustainable utilization of resources is critical for the continuous development of this society. Solar energy, as one of the renewables, shows great potential in replacing part of the traditional energy supplies since it is clean, abundant, and easily convertible to thermal, electrical, and biological energies. Using solar energy as the green driving force, interfacial solar evaporation is a promising way for clean water production to alleviate global water shortage, taking advantage of its high evaporation efficiency (more than 80%) and strong adaptability toward various water sources and fields. In recent years, various kinds of materials with diverse designs have been synthesized and applied in interfacial solar evaporation for clean water production. Herein, recent progress in interfacial solar evaporators for clean water production is systematically reviewed, based on the photothermal conversion mechanisms of solar absorbers, including carbonous, semiconductor‐based, and plasmatic ones. Furthermore, key design factors and strategies in interfacial solar evaporators are reviewed and discussed from material and structural design point of view, such as water transport, thermal management, latent heat for water vaporization, and salt accumulation. Finally, some perspectives related to resolving existing problems in the field are given.

Wood-inspired polypyrrole/cellulose aerogels with vertically aligned channels prepared by facile freeze-casting for efficient interfacial solar evaporation

“…4 Up to now, tremendous efforts have been made to improve the evaporation performance in different aspects, including speeding up water delivery, proper thermal management for less heat loss, lowering energy demand for evaporation and unique designs for alleviating salt accumulation. 3,5–17…”

“…3,4 Typically, a suitable solar-thermal-conversion material is located on the surface of evaporators to harvest and convert solar energy to thermal energy, and at the same time, water is transported to the surface by capillary effect. 5 Evaporation mainly happens at the interface of air and water on the surface of evaporators, which could not only reduce the usage of solar-thermal-conversion materials, but also signicantly suppress the superuous heat loss, leading to a relatively high efficiency. 4 Up to now, tremendous efforts have been made to improve the evaporation performance in different aspects, including speeding up water delivery, proper thermal management for less heat loss, lowering energy demand for evaporation and unique designs for alleviating salt accumulation.…”

“…4 Up to now, tremendous efforts have been made to improve the evaporation performance in different aspects, including speeding up water delivery, proper thermal management for less heat loss, lowering energy demand for evaporation and unique designs for alleviating salt accumulation. 3,[5][6][7][8][9][10][11][12][13][14][15][16][17] Nature provides abundant resources to inspire us to make material innovations. Wood, which possesses some unique characteristics, such as a naturally porous structure with vertically aligned channels, an abundance of hydrophilic functional groups, low thermal conductivity, cost-effectiveness, low toxicity, and easy access, has been regarded as a suitable substrate material for solar evaporators.…”

“…19,42,43 Moreover, the polymerization of its monomer, pyrrole (Py), could happen at room temperature (or under icy conditions) using oxidants as the initiator. 5 This facile synthesis also provides a big competitive edge compared with other solarthermal-conversion materials which need complicated processes for fabrication. 19 Inspired by the wood structure and its unique properties, in this work, porous cellulose aerogels were prepared as the substrate of a solar evaporator.…”

Carbon Dots‐Assisted Rapid Synthesis of Polypyrrole with High Uniformity for Efficient Solar‐Driven Water Evaporation

“…[5][6][7] A desirable evaporator should effectively convert the absorbed solar energy into the heat, localize the heat at the air-water interface, and be able to realize the sufficient water transport and fast vapor escape. [8][9][10] Now, various evaporators have been developed. [11][12][13][14][15][16][17][18][19][20][21] Despite the success of existing evaporators, these evaporators rely on expensive and complex preparation technology, and it is also challenging for a designed evaporator to perfectly balance these functions.…”