Recent advances in interfacial solar vapor generation: clean water production and beyond

Interfacial solar vapor generation (ISVG) was first proposed in 2014 and it has gained more and more attention from academia due to its tremendous improvement in evaporation efficiency compared with previous bottom and volumetric heating designs. With significant efforts put into this field, the current evaporation rate of the system can attain 4 kg m⁻² h⁻¹ under one sun irradiation. To catch up with the up-to-date development of ISVG systems, we prepare this review article to summarize the recent development in this field. In this review, we first introduce the constituent elements of an ISVG system, namely substrates and photothermal materials. Following this, several fabrication techniques for ISVG systems are highlighted to enable all-in-one ISVG architecture designs. The central parts of this review include the design principles and optimization strategies of ISVG systems, salt rejection and condensation strategies. Finally, various application scenarios, including seawater desalination, sterilization, and water-electricity/water-fuel production, are introduced in detail, followed by conclusions and future perspectives. ISVG is a green and low-cost technique for producing clean water driven by solar energy, which shows great application potential in remote and off-grid regions. With continuous efforts and improvement, it is envisioned that ISVG will become a complementary technique to current water treatment technologies soon.