Interfacial solar vapor generation for desalination and brine treatment: Evaluating current strategies of solving scaling

A self‐salt‐cleaning architecture in cold vapor generation system for hypersaline brines

“…No clear salt crystals were observed on this 12‐layer structure after 10‐hour continuous operation. The best evaporation rate for the 12‐layer structure reached 2.66 kg m −2 h −1 (see the second red sphere), representing one of the best reported evaporation rates under 1 sun illumination (e.g., 4,11,16 ). When we further pushed the salinity to 10 wt% and performed the same 10‐hour operation, the salt occupancies on the flat and 1‐layer umbrella structures are 64.7% and 12.6%, respectively (as shown in Figure 2C).…”

“…Recently, solar‐driven interfacial evaporation received extensive attention due to their potentials in water, energy and environmental sustainability 5–7 . This technique evaporates water from brines or contaminated water using solar thermal effects and is promising to realize zero‐liquid‐discharge (ZLD) desalination 7–11 . In the past decade, researchers developed various advanced materials, 9,12–16 improved thermal management strategies and systems, 8,12,17–20 and cooling technologies 21–23 to improve the overall water productivity.…”

“…Salt accumulation on the solar absorber is considered generally undesirable as solar absorbers are mostly black to enable maximum absorption of the sunlight. Formation of salt on the absorber hinders stable vapor generation and gradually deteriorates the solar thermal performance (e.g., 11,31,32 ). Recently, self‐cleaning strategies were proposed to minimize the maintenance requirement for solar vapor generation (e.g., using prewetting, 10 wood, 33–36 and specially designed geometry structures) 9,17,24,26,37–42 .…”

“…[5][6][7] This technique evaporates water from brines or contaminated water using solar thermal effects and is promising to realize zero-liquid-discharge (ZLD) desalination. [7][8][9][10][11] In the past decade, researchers developed various advanced materials, 9,[12][13][14][15][16] improved thermal management strategies and systems, 8,12,[17][18][19][20] and cooling technologies [21][22][23] to improve the overall water productivity. Competitions in higher energy conversion efficiency and evaporation rates, 5,9,15,19,24 lower manufacturing costs, 7,[25][26][27] less maintenance requirements, 5,6,9,10,26,28 and multifunctionalization 29,30 are major goals.…”

Interfacial solar evaporator for brine treatment: the importance of resilience to high salinity

“…The process used a system of self-assembled particles made of an expanded polystyrene (EPS) core and graphene oxide (GO) shell to introduce interfacial solar evaporation that enabled complete water-solute separation. Interfacial solar evaporation has been widely studied in recent years as a sustainable technology with regard to addressing water-energy challenges [ 4 ]. The photothermal, adsorptive, charge, lamellar and multifunctional properties of GO have made it a popular material for potential application in desalination [ 5 , 6 ].…”