Synthesis and thermal characterization of the C-S-H/paraffin composite phase change material utilizing a discontinuous two-step nucleation method  

基于非连续两步成核的C-S-H/paraffin相变材料制备及储热性能

作　　者：Shen Xuyan Feng Pan Zhang Qi 沈叙言;冯攀;张琪(东南大学材料科学与工程学院,南京211189;高性能土木工程材料国家重点实验室,南京210008)

机构地区：[1]School of Materials Science and Engineering,Southeast University,Nanjing 211189,China [2]State Key Laboratory of High Performance Civil Engineering Materials,Nanjing 210008,China

出　　处：《Journal of Southeast University(English Edition)》2024年第4期327-335,共9页东南大学学报（英文版）

基　　金：The National Natural Science Foundation of China(No.52122802,52078126);Jiangsu Provincial Department of Science and Technology Innovation Support Program(No.BK20222004,BZ2022036).

摘　　要：The novel calcium-silicate-hydrate(C-S-H)/paraffin composite phase change materials were synthesized using a discontinuous two-step nucleation method.Initially,the C-S-H precursor is separated and dried,followed by immersion in an aqueous environment to transform it into C-S-H.This two-step nucleation approach results in C-S-H with a specific surface area of 497.2 m^(2)/g,achieved by preventing C-S-H foil overlapping and refining its pore structure.When impregnated with paraffin,the novel C-S-H/paraffin composite exhibits superior thermal properties,such as a higher potential heat value of 148.3 J/g and an encapsulation efficiency of 81.6%,outperforming conventional C-S-H.Moreover,the composite material demonstrates excellent cyclic performance,indicating its potential for building thermal storage compared to other paraffin-based composites.Compared with the conventional method,this simple technology,which only adds conversion and centrifugation steps,does not negatively impact preparation costs,the environment,and resource consumption.This study provides valuable theoretical insights for designing thermal storage concrete materials and advancing building heat management.通过非连续式的两步成核方法制备了新型C-S-H/石蜡相变材料,即在前驱体形成后将其分离并干燥,重新置于水中转化为C-S-H.由于解决了C-S-H箔片的相互遮盖问题以及孔径的大幅细化,通过非连续式两步成核方法制备的C-S-H比表面积高达497.2 m^(2)/g.与常规方法制备的C-S-H相比,在浸渍石蜡后,C-S-H/paraffin复合材料具有更高的潜热值(148.3 J/g)和更高的封装效率(81.6%),并显示出良好的循环性能.相比其他石蜡基的相变储能材料,这种新方法制备的C-S-H材料在封装效率和潜热值上展现出明显优势.该方法工艺简单,相比常规方法仅增加了一次转化和离心,成本的提高可以忽略,同时对环境、资源无负面影响.该研究对相变混凝土、建筑热管理等技术具有理论指导意义.

关 键 词：two-step nucleation C-S-H PARAFFIN phase change materials composite building thermal management 

分 类 号：TU506[建筑科学—建筑技术科学]