Solid-Solutioned Homojunction Nanoplates with Disordered Lattice: A Promising Approach toward 鈥淧honon Glass Electron Crystal鈥?Thermoelectric Materials

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• 作者：Chong Xiao ; Jie Xu ; Boxiao Cao ; Kun Li ; Mingguang Kong ; Yi Xie
• 刊名：The Journal of the American Chemical Society
• 出版年：2012
• 出版时间：May 9, 2012
• 年：2012
• 卷：134
• 期：18
• 页码：7971-7977
• 全文大小：382K
• 年卷期：v.134,no.18(May 9, 2012)
• ISSN：1520-5126

文摘

The concept of 鈥減honon glass electron crystal鈥?(PGEC) was proposed in the mid-1990s to maximize the ZT value for thermoelectric materials, based on its combined advantages of low thermal conductivity as in a glass but high electricity as in a well-ordered crystal. Although a great amount of research in complex materials systems for achieving this concept has been done, a perfect 鈥淧GEC鈥?material has not been acquired yet. Herein, we first put forward a solid-solutioned homojunction in high temperature phase with disordered lattice, which possesses both high electrical conductivity and low thermal conductivity, as an effective way to optimize the low/mid-temperature thermoelectric property. As an example, nonambient cubic phase AgBiSe₂ was successfully stabilized to room temperature through the formation of a solid solution by Sb incorporation for the first time, and furthermore, in situ formed homojunctions on the surface of solid-solutioned nanoplates were also first achieved through a simple colloidal method. A significant enhancement of thermoelectric performance at low/mid-temperature was realized through synergistical regulation on electronic and thermal transport. As a result, compared to that of original AgBiSe₂ (ZT = 0.03 at 550 K), the ZT value of AgBi_0.5Sb_0.5Se₂ was increased to 0.51 at 550 K by the formation of a solid solution, and then further increased to 1.07 at 550 K by the formation of solid-solutioned homojunction.