Ministry of Education Key Laboratory for the Green Preparation and Application of Functional Materials, Hubei University, Wuhan430062, People's Republic of China.
Macheng Industrial Technology Research Institute, Hubei University, Macheng438300, People's Republic of China.
ACS Appl Mater Interfaces. 2023 Jan 25;15(3):4799-4813. doi: 10.1021/acsami.2c18774. Epub 2023 Jan 12.
Energy-free radiative cooling is a green and ideal solution to replace air conditioning by reflecting sunlight spontaneously and radiating excess heat through atmospheric transparency windows to outer space for passive cooling. However, most radiative cooling materials are susceptible to contamination by dust, rain, etc., which reduces the cooling capacity in outdoor environments. Herein, we report on a superhydrophobic daytime radiative cooling coating based on SiOcoated glass bubble (SiO-GB) powder that achieves strong sunlight reflectivity (96%) and high mid-infrared emissivity (98%), effectively producing an ambient temperature drop of 11.1 °C in direct outdoor sunlight. More importantly, the coating has good superhydrophobic properties with a water contact angle of 157°, which allows the coating to be self-cleaning to keep the coating free from contamination and effectively maintain good radiation cooling performance. In addition, the prepared coatings remain hydrophobic and keep good radiative cooling properties when exposed to different pH solutions and long-term exposure to UV irradiation, which has important implications for sustainable applications, and our work holds great promise for the energy efficiency of building materials and their long-term outdoor service.
无能耗辐射制冷是一种绿色理想的解决方案，可以通过自发反射阳光并通过大气透明窗口将多余热量辐射到太空中来代替空调，实现被动冷却。然而，大多数辐射冷却材料容易受到灰尘、雨水等的污染，这会降低户外环境中的冷却能力。在此，我们报告了一种基于 SiO 涂层玻璃泡（SiO-GB）粉末的超疏水日间辐射冷却涂层，该涂层实现了强阳光反射率（96%）和高中红外发射率（98%），在直接户外阳光照射下有效产生了 11.1°C 的环境温度下降。更重要的是，该涂层具有良好的超疏水性，水接触角为 157°，这使得涂层具有自清洁功能，使其免受污染，并有效地保持良好的辐射冷却性能。此外，所制备的涂层在暴露于不同 pH 值的溶液和长期暴露于紫外光下时仍保持疏水性和良好的辐射冷却性能，这对可持续应用具有重要意义，我们的工作为建筑材料的能源效率及其长期户外服务提供了广阔的前景。
