A solution-processed radiative cooling glass

Abstract

Passive daytime radiative cooling materials could reduce the energy needed for building cooling up to 60% by reflecting sunlight and emitting long-wave infrared (LWIR) radiation into the cold Universe (~3 kelvin). However, developing passive cooling structures that are both practical to manufacture and apply while also displaying long-term environmental stability is challenging. We developed a randomized photonic composite consisting of a microporous glass framework that features selective LWIR emission along with relatively high solar reflectance and aluminum oxide particles that strongly scatter sunlight and prevent densification of the porous structure during manufacturing. This microporous glass coating enables a temperature drop of ~3.5° and 4°C even under high-humidity conditions (up to 80%) during midday and nighttime, respectively. This radiative “cooling glass” coating maintains high solar reflectance even when exposed to harsh conditions, including water, ultraviolet radiation, soiling, and high temperatures.

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 reectance. One is to prepare polymer particle composite materials containing micro-nano llers with a high refractive index such as Al 2 O 3 , [11][12][13] TiO 2 , [14][15][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 signicantly enhance the solar reectance.…”

Durable and Scalable Superhydrophobic Colored Composite Coating for Subambient Daytime Radiative Cooling

“…The energy consumption required for cooling increased continually with the growing global warming, which has further exacerbated the greenhouse effect and environmental issues. − An environmentally friendly cooling technique known as passive daytime radiative cooling − could cool objects by reflecting sunlight in the solar spectrum (0.3–2.5 μm) and by simultaneously radiating excessive heat by the atmospheric transparency window (8–13 μm) to the cold outer space spontaneously. , Numerous radiative cooling materials with exceptional solar reflectance and infrared emissivity − have been demonstrated, which show potential cooling applications in architecture, − personal thermal management, − photovoltaic modules, , water harvesting, , etc. However, the requirement for high reflectance of radiative cooling results in materials that are primarily white in color, which restricts the possibilities for practical applications.…”

POSS/PVTMS aerogels for passive cooling and THz communication via cross-linking density regulation and nanoscale bimodal design

“…13 For example, using metal materials ( via coating and random distribution) has been proven to be an effective way to prepare highly efficient sunlight reflectors and PDRC materials. 14–17 Li et al 18 introduced magnesium–aluminum layered double hydroxide (MgAl-LDH) nanoflakes into delignified wood sawdust by a freeze-drying assisted lamination process for simultaneous PDRC and flame-retardant applications. Xue et al 16 randomly distributed TiO 2 in a polystyrene-acrylate emulsion matrix, producing the hybrid metal/polymer layer with high solar reflectance.…”

“…Xue et al 16 randomly distributed TiO 2 in a polystyrene-acrylate emulsion matrix, producing the hybrid metal/polymer layer with high solar reflectance. Zhao et al 17 introduced Al 2 O 3 (practical) into a glass system, due to the similar diameter between Al 2 O 3 (practical) (500 nm) and solar light wavelength (300–2500 nm), and hence greatly enhanced the Mie scattering efficiency and solar light reflectivity (>96%). However, these metal materials with high dielectric permittivity and permeability exhibit high reflection of communication electromagnetic waves at the air/material interface, 19 which is not beneficial for preparing materials with both desired passive cooling properties and terahertz (THz) transmission properties.…”