Publication

Abstract : Solar thermal evaporation (STE) is a promising advanced technique to purify contaminated water under the influence of solar light. Naturally, cement has served as a binder in masonry-related applications and possesses light-absorbing properties. Herein, we fabricated a cost-effective high-durable cement/carbon/polyurethane foam (CCPF) composite material as a solar-driven evaporator. It provided an excellent evaporation rate of ∼2.4 kg m−2 h−1 under one sun (1 kW/m2) illumination. The CCPF exhibits a high solar light absorbance due to the presence of carbon. Also, the high-interconnected porous foam provides the self-floating ability to maximize heat localization. Simultaneously, the interconnected crisscross porous foam and the porous activated carbon coat on the air-water interface behave like a highly concentrated dye water filter, salt-water filter, and high density muddy water filter. Moreover, the super hydrophilic surface of CCPF and the addition of polyurethane (PU) foam ensure adequate water supply. Complete wastewater filtering ability was confirmed by UV–Vis spectral analysis. As-fabricated composite can attain the maximum surface temperature of 62 °C under one sun illumination for 1 h. The stability and adhesive strength of the coating were confirmed from successive 60 days of water treatment. No carbon was excreted from the device even after 60 days of the experiment. The small size solar still setup was fabricated with an area of 30 × 30 cm2 to show the performance of the device under ambient conditions. Collection of 140–180 ml ultrapure water from the device under ∼0.6 kW/m2 (variable solar intensity) at environment temperature 30–32 °C in 4–5 h. Therefore, this easily fabricated, cost-effective, highly stable CCPF solar-driven evaporator can be used as a strategy for high water production on a potential scale for the long term.