Full-Spectrum Solar-to-Heat Conversion Membrane with Interfacial Plasmonic Heating Ability for High-Efficiency Desalination of Seawater

Abstract

The current challenge in solar thermal utilization is how to effectively convert full-spectrum sunlight into directly available thermal energy for applications at high conversion efficiency. Herein, we report a novel strategy for the construction of large-area porous CuS/polyethylene (PE) hybrid membrane as a superior interfacial plasmonic photothermal material for high-efficiency solar thermal conversion to produce steam generation off seawater. The single-layer CuS/PE membrane materials have effective full-spectra sunlight absorption, excellent solar-to-heat conversion ability, low thermal conductivity, good hydrophilicity, and open micro/nanoscopic porosity for capillarity and self-floating, etc. Impressively, a single piece of porous CuS/PE membrane under one sun illumination can exhibit a superior conversion efficiency of 63.9% from sunlight to heat of seawater evaporation. Meanwhile, the plasmonic photothermal CuS/PE membrane can be recycled at least 20 times. Therefore, with the demonstrated convenient fabrication process, low cost, and high evaporation efficiency, the single-layer porous CuS/PE membrane materials offer great promise to convert sunlight into thermal energy for practical applications of steam generation.

Recent Advances in Tungsten-Oxide-Based Materials and Their Applications

“…A solar-driven water evaporation process that utilizes sunlight as a renewable energy resource can be used in numerous practical applications. Such applications include freshwater production, desalination, and distillation (Hua et al, 2017;Shang et al, 2017;Awad et al, 2018;Kim et al, 2018). Solar heating designed as "airwater interface solar heating" has the ability to trap a wide solar spectrum selectively by strengthening the air-water interface (Wang et al, 2017d).…”

Harnessing Solar‐Driven Photothermal Effect toward the Water–Energy Nexus

“…[45] First, when the energy of incident light is higher than or equal to the bandgap of semiconductor, the electron-hole pairs will be motivated and generated within semiconductor. [47] In addition, a series of new narrow-bandgap semiconductors have been developed as the promising alternative to realize full-spectrum solar-to-heat, including CuS, [48,49] Ti 2 O 3 , [45] TiN, [50] TiAlN, [51] CuFeSe 2 , [52] and Te. However, most wide-bandgap semiconductors exhibit relatively narrow absorption wavelength.…”

“…[93] As a consequence, the effective and common solution is to reduce the contact area to minimize the conductive and radiative heat from the evaporation surface. Until now, a series of low thermal conductivity materials have been exploited as the insulating supporter, including polyethylene membrane (0.448 W m −1 K −1 ), [48] cotton (0.04 W m −1 K −1 ), [66] wood (0.11-0.36 W m −1 K −1 ), [64,122] polystyrene foam (≈0.04 W m −1 K −1 ), [65] and plant fiber sponges (0.103 W m −1 K −1 ), [123] and electrospun polyvinylidene fluoride (PVDF) layers ( Figure 5a). In this special structure, the bottom carbon foam is thermally insulating to reduce heat losses to the underlying bulk water, and the top exfoliated graphite layer acts as the solar absorber.…”

“…[41,60,70,71,138] Thanks to this unique structure, woodbased evaporator exhibited a higher water evaporation rate (1.31 kg m −2 h −1 ) than that of porous membrane-based evaporator (0.75 kg m −2 h −1 ) under simulated 1 sun illumination. [48] Copyright 2016, American Chemical Society. [62] For example, when a layer of VACNT arrays was used as solar steam generation, and its water evaporation rate was ten times higher than that Adv.…”

Effect of Pore Characteristics in Polyvinylidene Fluoride/Fumed Silica Membranes on Mass Flux in Solar-Assisted Evaporation Applications

“…However, although important, very little has been performed in the literature to demonstrate those effects experimentally in a continuous flow system [19][20][21][22]. All of the previously reported solar-assisted evaporation experiments [23][24][25][26][27][28][29][30] involved batch-mode setups. The batch mode setups do not involve the flow of water; therefore, we suspect that the accumulation of heat in the fluid over time is likely to occur and thus the ability to obtain a real correlation between physical membrane properties and the actual evaporation flux can be influenced.…”