Scalable, Patternable Glass‐Infiltrated Ceramic Radiative Coolers for Energy‐Saving Architectural Applications

Abstract

A huge concern on global climate/energy crises has triggered intense development of radiative coolers (RCs), which are promising green‐cooling technologies. The continuous efforts on RCs have fast‐tracked notable energy‐savings by minimizing solar absorption and maximizing thermal emission. Recently, in addition to spectral optimization, ceramic‐based thermally insulative RCs are reported to improve thermoregulation by suppressing heat gain from the surroundings. However, a high temperature co‐firing process of ceramic‐based thick film inevitably results in a large mismatch of structural parameters between designed and fabricated components, thereby breaking spectral optimization. Here, this article proposes a scalable, non‐shrinkable, patternable, and thermally insulative ceramic RC (SNPT‐RC) using a roll‐to‐roll process, which can fill a vital niche in the field of radiative cooling. A stand‐alone SNPT‐RC exhibits excellent thermal insulation (≈0.251 W m−1 K−1) with flame‐resistivity and high solar reflectance/long‐wave emissivity (≈96% and 92%, respectively). Alternate stacks of intermediate porous alumina/borosilicate (Al2O3‐BS) layers not only result in outstanding thermal and spectral characteristics, causing excellent sub‐ambient cooling (i.e., 7.05 °C cooling), but also non‐shrinkable feature. Moreover, a perforated SNPT‐RC demonstrates its versatility as a breathable radiative cooling shade and as a semi‐transparent window, making it a highly promising technology for practical deployment in energy‐saving architecture.

Superhydrophobic and mechanical properties enhanced the electrospinning film with a multiscale micro-nano structure for high-efficiency radiation cooling

“…Thus, recently, two main strategies have been reported to promote the solar reflectance. One is to prepare polymer particle composite materials containing micro-nano fillers with a high refractive index such as Al 2 O 3 , 11–13 TiO 2 , 14–16 ZnO, 17,18 ZrO 2 , 19 and Y 2 O 3 . 7 Mandal et al 20 demonstrated that adopting Al 2 O 3 and BaSO 4 to construct a randomly distributed particle structure could significantly enhance the solar reflectance.…”

Development of High-Performance Flexible Radiative Cooling Film Using PDMS/TiO2 Microparticles

“…Despite the advantages of particle-based structures, they encounter significant challenges in practical applications [38]. The primary issues include the difficulty of achieving uniform dispersion of microparticles in a highly viscous medium, the risk of cracking caused by thermal shrinkage and expansion, and the use of toxic materials in the fabrication process [39,40]. When PMMA is employed as a medium for a particle-based structure, it poses challenges in terms of sustaining its performance for a long time on the exterior walls of buildings or vehicles due to its thermoplastic nature.…”

Hierarchically structured passive radiative cooling ceramic with high solar reflectivity

“…The trade-off between the optical properties and applicability has always posed a challenge for practical implementation of PRC technology in the real world. Recently, PRC designs using pure inorganic materials to achieve reliable stability offer insight for addressing this challenge ( 40 – 42 ). In this work, we designed a hierarchically porous PRC material in the form of a bulk ceramic, which can be easily obtained using accessible inorganic materials through facile fabrication processes.…”