Ion-dyed cellulose-based radiative cooling structural material

Abstract

Effectively regulating heat flow between buildings and their environment, through the use of infrared property-structural materials that passively regulate radiative heat dissipation, not only enhances thermal comfort but also offers a potentially cost-effective solution for energy conservation and countering global warming. However, fulfilling the demand for aesthetic appearance and effective display in real-life situations while maintaining infrared properties remains a significant impediment to the commercialization of structural materials. In this work, we utilized ion-dyed cellulose as the base material and employed gel-assisted and thermal pressing methods to produce ion-dyed cooling cellulose bulk. Experimental results demonstrate its bending strength reaching 111 MPa, and impact toughness reaching 79.8 kJ m−2. While offering a wide range of colors, it exhibits excellent radiative cooling performance. During days with strong solar radiation, three different colors of ion-dyed cooling cellulose bulk achieve temperature reductions of 2.2–3.9 °C. Moreover, the fabrication process is simple, cost-effective, and conducive to industrialization. This study provides a practical and theoretical foundation for the development and design of colored wood-based radiative cooling materials.