Research Achievements

Materials Science and
Engineering

  • Home
  • About MSE
  • Research Achievements
Neutral-Colored Transparent Radiative Cooler by Tailoring Solar Absorption with Punctured Bragg Reflectors
교수님성함
Heon Lee
저널명
Advanced Functional Materials
년도
2024

1d0fdff2ecb0efae596c31914e88aa06_1727326994_1573.jpg



Daytime radiative cooling (DRC) has emerged as a promising method for temperature reduction of surfaces exposed to sunlight, without energy consumption. Despite advancements in DRC design, existing reflector-based methodologies often lack transparency because of visible reflection, hindering the widespread application of this technology using glass. Efforts to address this challenge have led to the development of transparent radiative cooling (TRC), although efficient cooling during daylight remains challenging because of the dominant solar energy absorption. This paper proposes a novel TRC design comprising a polydimethylsiloxane (PDMS) emitter atop a transparent dual-reflector structure. An optimized Bragg reflector (OBR) and a 90 µm-hole-punctured Ag window screen reflector (WR) are used to reflect band A of the near-infrared (NIR) spectrum (0.74 < λ < 1.4 µm) and the overall solar spectrum, respectively. During the daytime, the proposed TRC lowers the temperature by 22.1 °C through the transparent dual reflector system, compared to a PDMS-coated glass. Thus, this approach optimizes the balance between solar reflection and visibility using a dual reflector, offering an optimal solution for applications requiring both cooling and transparency.