A strategy for accelerating condensation by radiative cooling with hydrophilic-hydrophobic surface

Using radiative cooling technology for dew collection is a promising solution to the freshwater resource crisis. Environmental factors such as solar radiation intensity, ambient temperature, and humidity can influence both the radiative cooling process and the condensation process. In this study, the influence mechanisms of environmental factors on the radiation condensation effect are studied through simulation. Then, TiO2 nanoparticles are sprayed on the surface of the PDMS film to form a hydrophobic -hydrophilic surface. The experimental research is conducted at an ambient temperature of 25 celcius and a relative humidity of 70%-90% to analyze the change in condensation water. The experimental results indicate that after TiO2 nanoparticles are added to PDMS film, the emissivity in the atmospheric transparency window and the surface hydrophilicity of the film are increased, which effectively improves the condensation effect. The condensation rate has reached 916.6 g center dot m- 2 center dot h-1. At 70% relative humidity, the condensation water of PDMS film with TiO2 nanoparticles increased by 58%, and the improvement effect is most significant at lower relative humidity. It has great application prospects in arid and water -scarce areas.