Structural stabilities and electrical properties of Ba 8 Ga 16− x Cu x Sn 30 single crystals under high temperatures
Year: 2016
Type: article
Abstract: Single crystalline samples of type-I and type-VIII Ba 8 Ga 16− x Cu x Sn 30 ( x = 0, 1) clathrates are prepared by the Sn-flux method. Effects of Cu-doping on stability and electrical properties of Ba 8 Ga 16 Sn 30 single crystal are explored by first-principle and experiment. All samples are heated to different high temperatures and maintained at these temperatures for 120 min and then cooled to room temperature to explore their structural stabilities. Results from DTA and powder x-ray diffraction analysis indicate that type-I Ba 8 Ga 16 Sn 30 structure is transformed into type-VIII phase after the sample has been heated to 185 °C. Type-VIII BGS is stable during heating and cooling, but type-VIII Ba 8 Ga 15 CuSn 30 decomposes into Sn and Ba(Ga/Sn) 4 during cooling. Meanwhile, the electrical properties of type-I samples are measured, their electrical conductivities are enhanced, and the Seebeck efficient is reduced with Cu substitution. The type-I samples after phase transformations show the electrical characteristics of type-VIII samples.
Source: Chinese Physics B
Authors: Jin-Song Wang, Feng Cheng, Hong-Xia Liu, De-Cong Li, Lan-Xian Shen, Shu-Kang Deng
Institutions: Yunnan Normal University, Yunnan Open University
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: bronze
OpenAlex ID: W2533630320