Effect of Sr Doping on Structure and Emittance of La_1-xSr_xMnO₃ Smart Thermal Control Films

Abstract:

Sr-doped lanthanum manganite (La_1-xSr_xMnO₃) is characteristic of thermochromic, which can act as a smart thermal control material used in the variable-emittance devices. In the present study, La_1-xSr_xMnO₃ thin films were prepared on MgO(100) substrates by pulsed laser deposition, and the effect of Sr-doping (x = 0 ~ 0.4) on the structure and infrared emissivity was investigated. Single-phased La_1-xSr_xMnO₃ films with (100)-orientation were obtained, which showed a dense texture with smooth surface. The ratio of Mn⁴⁺/Mn³⁺ in the films was increased with increasing Sr doping, leading to the enhancement in double-exchange interaction and electrical conductivity. As a result, the phase transition from metal to insulator was observed with the increasing of test temperature. For the La_0.8Sr_0.2MnO₃ thin film, a large value of emittance (De = 0.28) was obtained, indicating good variable-emittance by appropriate Sr doping.

• Periodical: Key Engineering Materials (Volumes 602-603)
• Pages: 902-905
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.602-603.902
• Online since: March 2014
• Authors: Yong Jun Shen, Chuan Bin Wang, Ling Li, Qiang Shen, Lian Meng Zhang
• Keywords: Emittance, La_1-xSr_xMnO₃, Pulsed Laser Deposition, Smart Thermal Control, Sr Doping

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