Design and construction of mesoporous silica/n-eicosane phase-change nanocomposites for supercooling depression and heat transfer enhancement
Design and construction of mesoporous silica/n-eicosane phase-change nanocomposites for supercooling depression and heat transfer enhancement
复制标题
用于降低过冷和增强传热的介孔二氧化硅/正二十烷相变纳米复合材料的设计和构建
DOI:
10.1016/j.energy.2019.116075
复制
发表时间:
2019-12-01
期刊:
影响因子:
9
通讯作者:
Wu, Dezhen
中科院分区:
文献类型:
--
作者:
Liu, Huan;Niu, Jinfei;Wu, Dezhen
Traditional micro- or nanoencapsulation of phase change materials (PCMs) generally results in high supercooling and slow thermal response. Hereby, we designed and synthesized two types of meso-silica/n-eicosane phase-change nanocomposites in the forms of uniform nanospheres and core-shell structured nanocapsules through self-templating strategy. The meso-silica/n-eicosane nanospheres have a disordered worm-like mesopore nanostructure, whereas the meso-silica/n-eicosane nanocapsules show a 3D cubic cage-like mesoporous structure for the core and a solid silica layer for the shell. These two types of phase-change nanocomposites achieved superior thermal performance including a good thermal storage capability, high thermal stability, good shape stability and satisfactory phase-change reliability. Most of all, owing to the formation of specific hierarchical nanostructures, both of them achieved a significant enhancement in thermal conductivity and effective depression in supercooling. Compared to the conventional silica/n-eicosane microcapsules, these two types of phase-change nanocomposites exhibited a shorter heat-charging period due to good thermal conduction by their interconnecting mesopores silica matrix, but a longer heat-discharging period because of the internal narrow mesopores resulting in crystallization confinement of encapsulated n-eicosane. With low supercooling and rapid thermal response, the phase-change nanocomposites developed by this work exhibit a great potential for hi-tech applications in fast temperature regulation and precise thermal management. (C) 2019 Elsevier Ltd. All rights reserved.