Abstract

Solar water evaporation is vital for addressing global water scarcity, particularly in regions with limited freshwater. Through the utilization of photothermal materials, solar water evaporation harnesses solar radiation to generate heat, which in turn accelerates the evaporation of water, producing clean drinking water. Subsequently, the vapor is condensed to produce fresh water, offering a sustainable solution to water scarcity. This research field has garnered immense scientific interest, with over six thousand publications. Reported solar absorber evaporation rates exceed 100 kg m−2 h−1 under one sun irradiation, far surpassing the theoretical limit of 1.47 kg m−2 h−1 achievable on two-dimensional absorber surfaces, assuming constant latent heat at 2444 J g−1. This review addresses this significant discrepancy in theoretical and practical values. A cut-off of 3 kg m−2 h−1 (under one sun irradiation) is considered to narrow focus, facilitating analysis of high-rate evaporators. Critical challenges and factors contributing to high evaporation rates are discussed, providing comprehensive insights into field advancements.