A review of natural materials for solar evaporation

Abstract

One way to harvest solar energy is to produce steam from liquid water. Steam can be used to provide freshwater even in a harsh environment, with extreme temperature and low groundwater supplies. It can also be extracted from polluted soil or water, purifying the water in the process at the same time. Water evaporation systems are energy effective, with efficiencies ranging from 60% to over 90%. Furthermore, they can be cost-effective and have a low environmental impact, using the right materials. In this article, we will review natural materials, mainly of biological origin, proposed for solar evaporation, from wood and plants to algae and other atypical biomass such as fungi or wastes such as pomelo peels, through gels and foams, raw or charred. Their evaporation effectiveness will be presented and discussed, as well as their energy efficiency. This timely review suggests the suitability of natural materials for this application and reports on the progress that has already been achieved, as well as on the advances that remain to be made to improve the performance of these low cost, low environmental impact but high performance systems.

Modelling heat and mass transfer in solar evaporation systems

“…The numerical model has therefore been validated and we can conclude that it can be used to simulate water evaporation in the following. This validation was done on the basis of the results obtained with tannin foam, but this material did not show particularly interesting performances compared to other materials reported in the literature, and for which the evaporation rate were close to 1.3 kg m -2 h -1 [17]. We now extend the application of this model to these more efficient materials in terms of solar evaporation.…”

Carbon Materials for Solar Water Evaporation and Desalination

“…From the viewpoint of structures, the multiply channels for water transport in plants are the favorable structure for water supply in SVG; from the viewpoint of materials, cellulose-based components are strong candidates for SVG systems due to the good hydrophilicity and low thermal conductivity. [42,82]…”

“…Some finely tailored structured systems in the lab-scale may present excellent SVG performance, but the expensive and delicate fabrication routes make their continuous mass production less possible. Scalable and cost-effective materials, such as biomass-derived materials, [82,124] amorphous carbon as well as plastic products (like bubble film [59] ), and assorted facile production methods (like 3D printing [125] ) will benefit the whole academia and industry.…”

Highly Efficient Solar Steam Generation under Low Solar Flux via Carbon‐Nanotube‐Modified Sugarcane

“…[8][9][10] The solar-thermal material plays a crucial role and an optimal absorber should satisfy several characteristics: 1) strong and broadband light absorption; 2) excellent thermal management to minimize the heat loss; and 3) porous structure for water transport. [11,12] Various light absorbers such as carbon foam, [13,14] graphene, [15,16] carbon nanotubes (CNTs), [17,18] metal nanomaterials, [19,20] biomass-based materials, [21][22][23][24][25] and other materials [26] have been used as light-to-heat conversion materials for efficient solar steam evaporation. Although great efforts have been made, the practical applications of most absorbers are relatively limited due to the high cost, complicated fabrication, or poor efficiency under low solar flux.…”