Highly Efficient Photothermal Conversion and Water Transport during Solar Evaporation Enabled by Amorphous Hollow Multishelled Nanocomposites

Abstract

Solar evaporation, which enables water purification without consuming fossil fuels, has been considered the most promising strategy to address global scarcity of drinkable water. However, the suboptimal structure and composition designs still result in a trade‐off between photothermal conversion, water transport, and tolerance to harsh environments. Here, an ultrastable amorphous Ta2O5/C nanocomposite is designed with a hollow multishelled structure (HoMS) for solar evaporation. This HoMS results in highly efficient photoabsorption and photothermal conversion, as well as a decrease of the actual water evaporation enthalpy. A superfast evaporation speed of 4.02 kg m−2 h−1 is achieved. More importantly, a World Health Organization standard drinkable water can be achieved from seawater, heavy‐metal‐ and bacteria‐containing water, and even from extremely acidic/alkaline or radioactive water sources. Notably, the concentration of pseudovirus SC2‐P can be decreased by 6 orders of magnitude after evaporation.

Progress and Perspectives of Hollow Multishelled Structures

“…Copyright (2017) Wiley‐VCH. (g—l) Adapted with permission from ref [66]. Copyright (2021) Wiley‐VCH.…”

“…Ta 2 O 5 /C HoMS (Figures 6g—l) with the crystalline property and carbon ratio tuned through controlling the annealing temperature and annealing duration. [ 66 ] The EXAFS results indicate that the length of the Ta—O bond is shorter in the amorphous sample than that in the crystal one. COMSOL multiphysics analysis reveals that the amorphous Ta 2 O 5 /C HoMS generates stronger heat accumulation, leading to a higher temperature in the inner shell.…”

Cost‐Effective Fabrication of Micro‐Nanostructured Superhydrophobic Polyethylene/Graphene Foam with Self‐Floating, Optical Trapping, Acid‐/Alkali Resistance for Efficient Photothermal Deicing and Interfacial Evaporation

“…[8][9][10] The application of various solar evaporators in water desalination has been widely investigated over the past decade. [11][12][13][14][15] Accordingly, tremendous efforts have been devoted to enhancing the evaporation efficiency by increasing sunlight utilization within a broadband wavelength range, minimizing parasitic thermal loss, and constructing unimpeded vapor escape channels. Based on the aforementioned understanding, materials such as semiconductors, conjugated polymers, and plasmonic metals have been prepared to improve sunlight absorption and light to heat conversion efficiency.…”

Self‐Assembled Supercrystals Enhance the Photothermal Conversion for Solar Evaporation and Water Purification

“…[1][2][3] In some areas, water resources must be continuously obtained from extreme sources including acidic/alkaline, radioactive, and highly infectious virus-containing water. [4][5][6][7][8] Solar evaporation is considered to be the most environmentally by controlling the growth conditions, followed by changes in the photothermal properties. [18,19] In addition, the self-assembly exhibits better properties than isolated NPs because of the collective properties related to the coupling effect of the building blocks of the self-assembly.…”