20.500.12556/RUL-190055 From flat to structured geometry-driven dual-mode radiative emitters for simultaneous hotspot cooling and water harvesting Radiative cooling has been developed for two largely separate functions: passive thermal management and atmospheric water harvesting (AWH). Combining them on a single surface under an imposed heat load is intrinsically difficult, as hotspot cooling raises the emitter temperature, whereas condensation requires sustained sub-dew-point regions. Here we establish, to our knowledge, a previously unreported geometry-driven co-functional regime in which a localized hotspot is coupled to an extended planar or pyramidal radiative emitter. Lateral heat spreading creates a warm, dry zone near the hotspot while preserving cooler peripheral regions for dew formation, allowing the same passive platform to reject heat and harvest water simultaneously. We combine angle-resolved optical characterization, raytracing, coupled heat and mass transfer modelling, and outdoor experiments. At a hotspot heat flux of 1021 W m$^{−2}$, the largest planar emitter and 45° pyramidal emitter retain dew fluxes of 9.3 and 7.9 g m▫$^{−2}$▫ h▫$^{−1}$▫, respectively, while lowering the near-hotspot temperature by more than 45 °C relative to a non-concentrated control. At 1500 W m$^{−2}$, the same architectures keep the hotspot below 20 °C, whereas the control approaches 85 °C. Finally, an experiment-calibrated global assessment further identifies where this regime is climatically accessible. These results provide a general framework for the passive co-management of localized heat and atmospheric water harvesting. radiative sky cooling materials atmospheric water harvesting hotspot cooling heat and mass transfer ray tracing numerical simulations optical characteristics of materials dnevno-sevalni materiali pridobivanje vode iz atmosfere hlajenje vročih točk prenos toplote in snovi sledenje žarkom numerične simulacije optične lastnosti materialov true false true Angleški jezik Slovenski jezik Članek v reviji 2026-10-21 10:09:59 2026-10-21 10:10:06 2026-10-22 04:13:19 0000-00-00 00:00:00 2026 0 0 Str. 7064-7088 iss. 20 Vol. 19 2026 0000-00-00 Zaloznikova Objavljeno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 536.24:628.116 1754-5692 10.1039/d6ee04674f 301807875 Poredos_..._From_flat....pdf Poredos_..._From_flat....pdf 1 F0B8FE8D7513182092A683B52D00D1C2 7af96115a15cc4c913e817df8406cd59cbd35a019888c71aee0f13874b05c712 5595ab81-cd27-11f1-8bc5-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=251048 https://pubs.rsc.org/ee/article/doi/10.1039/d6ee04674f/1360761/From-flat-to-structured-geometry-driven-dual-mode 1 a2e26b07-cd26-11f1-8bc5-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=251047 Fakulteta za strojništvo 0 0 0