Novel and durable composite phase change thermal energy storage materials with controllable melting temperature. (30th September 2021)

• Record Type: Journal Article
• Authors: Wei, Haiting; Yang, Shuiyuan; Wang, Cuiping; Qiu, Changrui; Lin, Kairui; Han, Jiajia; Lu, Yong; Liu, Xingjun
• Is Part Of: Journal of materials science & technology. Volume 86(2021)
• Page Start: 11
• Page End: 19
• Publication Date: 2021-09-30
• Subjects: Al-Si -- Al2O3-AlN -- Durable -- Controllable melting temperature -- Phase change thermal storage material; Metals -- Periodicals; Materials science -- Periodicals; Materials science; Metals; Periodicals; 620.1105
• DOI: 10.1016/j.jmst.2020.12.071
• Languages: English
• ISSNs: 1005-0302

Abstract

Graphical abstract: Highlights: Novel and durable Al-Si/Al2 O3 -AlN with tunable melting temperature were prepared. The Al-Si alloy and Al2 O3 shell were prepared by the reaction of SiO2 with melted Al. The shell crack repaired itself by nitriding of melted Al to form Al2 O3 -AlN shell. The Al2 O3 -AlN shell can obviously improve the thermal stability of composite PCM. The Al-Si/Al2 O3 -AlN can be used in thermal storage systems for more than 6 years. Abstract: The development of high temperature phase change materials (PCMs) with great comprehensive performance is significant in the future thermal energy storage system. In this study, novel and durable Al-Si/Al2 O3 -AlN composite PCMs with controllable melting temperature were successfully synthesized by using pristine Al powder as raw material and tetraethyl orthosilicate as SiO2 source. The Al2 O3 shell and Al-Si alloy were in-situ produced via the substitution reaction between molten Al and SiO2 . Importantly, the crack caused by the incomplete encapsulation of the Al2 O3 shell could repair itself by the nitridation reaction of internal molten Al and thereby forming a highly dense Al2 O3 -AlN composite shell. The produced dense Al2 O3 -AlN composite shell could significantly improve the thermal cycling stability of composite PCMs, and thus, the thermal storage density decrease of the Al-Si/Al2 O3 -AlN (59.8 J/g to 77.7 J/g) was far less than that of the Al-Si/Al2 O3 (118.5 J/g) after 3000 thermal cycles. Moreover, the synthesized Al-Si/Al2 O3 -AlN still exhibited a controllable melting temperature (571.5–637.9 ℃), relatively high thermal storage density (105.6–150.7 J/g), great dimensional stability and structural stability after 3000 thermal cycles. Hence, the synthesized Al-Si/Al2 O3 -AlN composite PCMs, as promising preferential thermal energy storage materials, can be stably used in the energy utilization efficiency improvement of various systems for more than 6 years.