Abstract:
The energy consumption of building during the operation phase for a large proportion of the global total energy consumption. The application of energy-saving materials in building envelopes is a critical strategy to reduce building energy consumption and regulate the building thermal environment. Conventional building thermal insulation materials such as rock wool and polyurethane rely only on thermal conduction mechanisms, which suffer from low thermal regulation efficiency, single function and poor durability. The development of novel energy-saving materials for green buildings with diverse thermal regulation mechanisms including thermal radiation, thermal conversion and heat conduction shows great potential for achieving efficient energy reduction through passive thermal regulation of green buildings. This paper systematically reviews the research progress of three types of novel energy-saving materials for green buildings with distinct thermal regulation mechanisms, namely radiative cooling materials, phase change materials and aerogel materials. The thermal regulation mechanisms of each material are elaborated, the classifications and performance characteristics of different materials are summarized, and the governing factors of thermal regulation as well as enhancement strategies are combed, and the common bottlenecks including complicated preparation process, unsatisfactory comprehensive properties and high cost which restricting the engineering application of novel energy-saving materials in green buildings are summarized. Subsequently, the strategies including multi-scale structural design, functional integration and system integration are proposed to construct a thermal insulation, heat storage and heat dissipation synergistic regulation system, which can address the drawbacks such as poor environmental adaptability, leakage and supercooling, single function, and poor service durability of single materials, and enhance the engineering application value of these materials in green buildings. Ultimately, the review is expected to provide theoretical reference for the research and development of high-efficiency and low-cost energy-saving materials of green building.