fig3

Figure 3. Passive radiative cooling materials and devices. (A) Colored passive radiative cooler (CPRC) integrated with wearable device; (B) photographs of CPRC on flexible substrate with wearable device. Reproduced with permission^[117]. Copyright 2018, Wiley-VCH GmbH, Weinheim; (C) high versatile porous SEBS substrate for on-skin electronics; (D) spray-printed Ag nanowire electrodes for on-skin electronics. Reproduced with permission^[118]. Copyright 2019, National Academy of Science; (E) NFC-based patch-type tissue oximeter (PTO) with nanovoid/microvoid polymer (NMVP); (F) optical image of device mounted on the forearm (G) temperature comparison of black elastomer (BE), white elastomer (WE), and NMVP. Reproduced with permission^[42]. Copyright 2021, Wiley-VCH GmbH, Weinheim; (H) conceptual illustration of gallium-based TES with multi-layered flexible and stretchable radiative cooler (m-FSRC); (I) outdoor temperature test of gallium-based transformative substrates with and without m-FSRC under the sunlight. Reproduced with permission^[43]. Copyright 2022, Wiley-VCH GmbH, Weinheim.