Self-adaptive integration of photothermal and radiative cooling for continuous energy harvesting from the sun and outer space

作者：Xianze Ao, Bowen Li, Bin Zhao, Mingke Hu, Hui Ren, Honglun Yang, Jie Liu, Jingyu Cao, Junsheng Feng, Yuanjun Yang, Zeming Qi, Liangbin Li, Chongwen Zou, Gang Pei · 发表于：Proceedings of the National Academy of Sciences · 年份：2022 · DOI：10.1073/pnas.2120557119 · 被引用次数：166 · 研究领域：Thermal Radiation and Cooling Technologies、Urban Heat Island Mitigation、Building Energy and Comfort Optimization

The sun (∼6,000 K) and outer space (∼3 K) are two significant renewable thermodynamic resources for human beings on Earth. The solar thermal conversion by photothermal (PT) and harvesting the coldness of outer space by radiative cooling (RC) have already attracted tremendous interest. However, most of the PT and RC approaches are static and monofunctional, which can only provide heating or cooling respectively under sunlight or darkness. Herein, a spectrally self-adaptive absorber/emitter (SSA/E) with strong solar absorption and switchable emissivity within the atmospheric window (i.e., 8 to 13 μm) was developed for the dynamic combination of PT and RC, corresponding to continuously efficient energy harvesting from the sun and rejecting energy to the universe. The as-fabricated SSA/E not only can be heated to ∼170 °C above ambient temperature under sunshine but also be cooled to 20 °C below ambient temperature, and thermal modeling captures the high energy harvesting efficiency of the SSA/E, enabling new technological capabilities.