Highly Efficient Solar Steam Generation from Activated Carbon Fiber Cloth with Matching Water Supply and Durable Fouling Resistance

Abstract

Interfacial solar steam generation is a green and promising technique to capture solar energy for brine water desalination; however, it still faces grand challenges of thermal loss and salt fouling to promote the practical application with high performance and durability. In this study, we report that activated carbon fiber cloth (ACFC) with hierarchical microstructures shows superior light-thermal property for solar steam generation. A well-matching water supply path manipulated by cotton fiber nonwoven fabrics (CFNF) can bring about a high evaporation rate of 1.59 kg m–2 h–1 with optimum conversion efficiency of 93.3% under 1 sun. Rate matching between the water supply and vapor evaporation is revealed to be of great importance to full heat exploitation and efficient solar desalination. Moreover, the extra water supply pathway provided by CFNF completely eliminates the salt fouling phenomenon via timely salt dredging, guaranteeing the durability of the self-cleaning solar steam generation system. Thus, the appropriate ACFC+CFNF configuration shows its great potential application in durable and highly efficient solar desalination.

Structure Architecting for Salt‐Rejecting Solar Interfacial Desalination to Achieve High‐Performance Evaporation With In Situ Energy Generation

“…More confined water pathways were proposed to minimize the contact with water, thus saving the heat from conduction loss. 2D water supply employs hydrophilic intermediary materials such as cellulose, [ 91 ] cotton and silk fabrics, [ 47,92–94 ] vertically oriented graphene structures, [ 81 ] air‐laid paper, [ 95 ] etc., for water delivery. In this way only a thin confined water layer is in contact with solar absorbers to supply water for evaporation (Figure 4b).…”

“…Liu and co‐workers recently reported a backward water transfer path (Figure 11d to dredge the salt produced by its upper evaporative fiber cloth (ACFC), and the bilayer structure can durably desalinate seawater with no salt fouling. [ 92 ] This instructive design can be imitated for those salt‐fouling photothermal materials to accelerate salt dissolution during the dark time. However, the above two strategies are at root passive ways to reject salt, and operation duration of solar evaporators could be constrained in the daytime.…”

Nanoenabled Photothermal Materials for Clean Water Production

“…They investigated the influence of the number of water channels on the vaporization efficiency rate. [ 181 ] Bai et al., 2019, proposed the fabrication of aerogel based on polyacrylamide possessing a 3D radial and centrosymmetric structure to accomplish anti‐gravity rapid and large‐spaced transport. [ 182 ] As the transfer of water is in direct incorporation with energy, more work is required to approach efficiently the water production and the rate of vapor generation and reduction of heat conduction losses along with the prevention of salt accumulation.…”

“…The second method involves the dissolution of salt ions by diffusion and convection from the evaporating surface into the underlying water body. [ 24,181,191 ] Hu et al. achieved the distillation rate of (15 wt%) for water salinity by surface‐carbonized bimodal porous balsa wood membrane.…”

Microvessel‐Assisted Environmental Thermal Energy Extraction Enabling 24‐Hour Continuous Interfacial Vapor Generation

“…Interfacial vapor generation has received tremendous research interests because it is a promising technique for seawater desalination, wastewater purification and electric power generation. [1][2][3][4][5] Conventional approaches for interfacial vapor generation generally utilize solar-to-thermal energy conversion, which adopts photothermal materials to produce high-temperature hot steam at the interface between water and floating evaporators. [6][7][8][9][10][11][12][13] Despite the usefulness, these approaches can only work for a limited daylight time (~8 h per day).…”