报告人：Dr. Jialai Wang
题目：Cenosphere-based Phase Change Materials Microcapsules for Thermal Energy Storage in Concretes
会议 ID：262 419 784
This study proposes a novel microencapsulation technique for phase change materials (PCMs) so that they can be integrated into concrete to produce thermally active concrete which can be used to reduce energy consumption of buildings. Microencapsulated PCMs (MEPCMs) provide a better utilization of PCMs with building materials. Existing MEPCMs encapsulate PCMs through synthesizing a polymer shell on the surface of PCM droplets. This shell not only is expensive, but also suffers many limitations such as low stiffness/strength, low thermal and chemical stability, high flammability, and low thermal conductivity. To overcome the drawbacks of the existing technologies, this study encapsulates PCMs into cenospheres. Cenospheres are hollow fly ash particles generated in coal burning power plants, having an aluminosilicate shell with high strength and stiffness. The large inner volume of the cenospheres makes them ideal candidate as microcapsules. However, the inner pore is not accessible to admixture because the shell is covered by a glass-crystalline nanosize film. To address this problem, chemical etching is employed to produce perforating holes through the shell. Liquid PCM can be easily loaded into the produced perforated cenospheres (PCs). The produced PCM microcapsules are referred to as CenoPCM, which can be directly added into concrete to produce structural concrete with thermal energy storage capacity. Additional function such as higher strength can also be achieved by applying appropriate coating to the CenoPCM.
Dr. Jialai Wang is a Professor at the Department of Civil, Construction, and Environmental engineering, The University of Alabama, Tuscaloosa, AL, USA. His research focuses decarbonization of built environments through material innovation. Some recent research topics include: 1) thermal energy storage materials for building energy efficiency; 2) Bio-inspired, renewable admixture and in-situ nanoparticle production technology for eco-efficiency and durability of cementitious materials; 3) low and non-clinker cementitious materials; and 4) upcycling construction and demolition waste and waste plastics for value-added products and carbon sequestration.