Biomass-Derived Polysilsesquioxane Nanofilament Reinforced Porous Aerogel for Durable Passive Radiative Cooling across All Day and Weather Conditions
Jie Xu, Kangwei Chen, Alessandro Maturilli, Alexandre Laroche, Lingshen Meng, J. Knollenberg, Stefan Seeger
Abstract
High Resolution Image Download MS PowerPoint Slide Passive radiative cooling (PRC) is a potentially sustainable strategy by reflecting sunlight (0.3–2.5 μm) and emitting heat through the atmospheric window (8–13 μm) without energy consumption. However, challenges remain due to high sunlight irradiance (1000 W m –2 ) during the day. Our research addresses these challenges by incorporating one-dimensional polysilsesquioxane nanofilaments (1D PSNFs) into micro- and nanoporous biomass-derived aerogels, forming a three-dimensional framework. The designed sustainable aerogel cooler achieves greater than 97% sunlight reflection and thermal emission, resulting in a cooling power of 138.6 W m –2 over 720 h, reducing ambient temperatures by 9 °C. In addition, the aerogel cooler demonstrates high thermal stability, low thermal conductivity (29.0 mW m –1 K –1 ), superhydrophobicity (water contact angle ∼175°), low density (44.43 kg/m 3 ), and a large surface area (137.84 m 2 /g). These features enable effective radiative cooling across various weather conditions, while also maintaining environmental sustainability.