Open Access

ARTICLE

Experimental Study on Properties of Nano-Silicon Modified Microencapsulated Phase Change Materials Mortar

Jian Xia^1,2, Xianzhong Hu¹, Yan Li¹, Wei Zhang^3,*

1 Fujian Academy of Building Research Co., Ltd., Fuzhou, 350025, China
2 Fujian Key Laboratory of Green Building Technology, Fuzhou, 350025, China
3 College of Civil Engineering, Fujian University of Technology, Fuzhou, 350118, China

* Corresponding Author: Wei Zhang. Email:

(This article belongs to the Special Issue: Sustainable and Durable Construction Materials)

Structural Durability & Health Monitoring 2025, 19(6), 1489-1506. https://doi.org/10.32604/sdhm.2025.065997

Received 27 March 2025; Accepted 03 July 2025; Issue published 17 November 2025

Abstract

Incorporating microencapsulated phase change materials (MPCM) into mortar enhances building thermal energy storage for energy savings but severely degrades compressive strength by replacing sand and creating pores. This study innovatively addresses this critical limitation by introducing nano-silicon (NS) as a modifier to fill pores and promote hydration in MPCM mortar. Twenty-five mixes with varying NS content from 0 to 4 weight percent and different MPCM contents were comprehensively tested for flowability, compressive strength, thermal conductivity, thermal energy storage via Differential Scanning Calorimetry, and microstructure via Scanning Electron Microscopy. Key quantitative results showed MPCM reduced mortar consistency while NS had minimal effect. Crucially, although MPCM decreased compressive strength, NS addition significantly counteracted this loss. Increasing NS content from 0 percent to 4 percent enhanced compressive strength by 12.53%, 14.21%, 25.49%, 21.70%, and 40.70%, respectively, across the tested MPCM levels. Thermal conductivity was primarily reduced by higher MPCM content leading to lower conductivity, with NS showing negligible and inconsistent influence. The phase change temperature of the modified mortar matched that of pure MPCM, although its relative latent heat slightly decreased. This work conclusively demonstrates the novel and effective use of nano-silicon, achieving up to a 40.7 percent strength recovery in MPCM mortar while preserving its essential phase change temperature and thermal conductivity reduction capability. This strategy presents a feasible pathway for developing high-performance, energy-efficient building composites.

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Keywords

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