Control of Thermal Radiation Characteristics Using Honeycomb Hole Patterns on Nano-Porous Structure

Passive radiative cooling offers a promising solution for reducing the energy consumption of cooling systems by reflecting sunlight (۰.۳-۳ μm) and emitting thermal radiation in the atmospheric window (۸-۱۳ μm). This cooling method does not require electrical power and can be applied to a variety of domains, including buildings, vehicles, solar cells, and in mitigating global warming. In this study, we explore the use of honeycomb-structured porous polymeric films with a photonic band gap as a passive cooling solution. The primary objective is to enhance the cooling efficiency through a photonic structure that allows selective emission in the thermal infrared region while reflecting sunlight. We design and fabricate a honeycomb-patterned polymeric film and investigate its thermal radiation properties under varying environmental conditions. The results demonstrate that these films, fabricated using dichloromethane and chloroform solutions, provide effective control over thermal radiation characteristics, offering a high net cooling power of ۴۵ W/m² under nighttime conditions with a temperature differential of approximately ۴۰ °C. The low-cost, scalable fabrication process of these films promises a broad application for selective radiative cooling technologies.

کلیدواژه ها:

Passive cooling ، Photonic crystals ، Honeycomb structure ، Selective emitters ، Thermal radiation