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.