Bamboo-derived phase change material with hierarchical structure for thermal energy storage of building

Heating, ventilation, and air conditioning consume 60 % of total energy of building. Phase change materials (PCMs) can help to reduce the energy consumption of heating and increase the building energy efficiency. In this study, three kinds of porous bamboo-derived materials (bamboo powder, bamboo charcoal, and activated bamboo carbon) were used as the framework/skeleton of paraffin to form PCMs with hierarchical structures. Each bamboo-derived material was produced in a low-cost and environmental method. In the hierarchical structure, generous macropores in bamboo powder typically provided sufficient space for loading paraffin and obtained high heat latent (99.81 J/g), while micropores in bamboo charcoal and activated carbon shown greater molecular force such as capillary force to prevent leakage. Further, the highest thermal conductivity of bamboo-derived PCMs was approximately 2.17 times higher than that of pure paraffin. The simulated temperature test shown that the bamboo-derived PCMs can effectively reduce temperature fluctuation with high thermal energy storage capacity. This study proved that the bamboo-based PCM is promising in building temperature regulation applications.