坩埚下降法生长SnSe单晶及其力学性能研究  

Mechanical Property of SnSe Single Crystal Prepared via Vertical Bridgman Method

作　　者：金敏 白旭东 赵素 张如林 陈玉奇 周丽娜 JIN Min;BAI Xudong;ZHAO Su;ZHANG Rulin;CHEN Yuqi;ZHOU Lina(College of Materials,Shanghai Dianji University,Shanghai 201306,China;School of Materials Science and Engineering,University of Shanghai for Science and Technology,Shanghai 200093,China)

机构地区：[1]上海电机学院材料学院,上海201306 [2]上海理工大学材料科学与工程学院,上海200093

出　　处：《无机材料学报》2021年第3期313-318,共6页Journal of Inorganic Materials

基　　金：Shanghai Natural Science Foundation(19ZR1419900)。

摘　　要：Ⅳ-ⅥSnSe单晶是一种引人注目的热电材料,不仅热电性能优异而且还具有环境友好的特征。本工作探索了一种制备SnSe单晶的技术,并对产品的力学性能进行研究。利用坩埚下降法成功生长了化学计量比准确的非掺杂SnSe单晶,其在室温下具有标准Pnma正交相结构。由于Sn层与Se层之间的结合力非常弱,SnSe单晶很容易沿(100)面解理。显微压痕测试表明SnSe单晶十分柔软,0.01~0.05 kg载荷下的平均显微维氏硬度HV仅为53 MPa。然而,得益于层内Sn和Se原子之间强烈的极性耦合,SnSe单晶沿(100)面却展现出了优异的断裂韧性。纳米划痕实验显示SnSe单晶(100)面在5~300 mN划痕压力范围内的摩擦系数COF可从0.09增加到0.8。本工作对完善SnSe单晶的力学性能信息具有重要意义。Ⅳ-ⅥSnSe single crystal is an attractive thermoelectric(TE)material due to its outstanding TE behavior and environment friendly charactistic.In this work,an effective way for SnSe single crystal growth was explored,and the mechanical property of the as-prepared product was investigated.Undoped SnSe single crystal with accurate stoichiometric ratio was successfully grown via a vertical Bridgman method.The as-grown SnSe single crystal has standard orthorhombic Pnma space group at room temperature.It is easy to cleave along(100)plane because of its weak link between adjacent Sn-Se layers.Microindentation test reveals that SnSe single crystal is a very soft material as its average Vickers microhardness HV is only 53 MPa under 0.01-0.05 kg applied loads.However,it displays excellent fracture toughness due to strong heteropolar bonds between Sn and Se atoms inside(100)plane.The friction coefficient COF on(100)is increased from 0.09 to 0.8 as the scratch load is added from 5 to 300 mN.This work is of great significance to provide the mechanical property of SnSe single crystal.

关 键 词：词:SnSe单晶 坩埚下降法 力学性能 

分 类 号：TQ174[化学工程—陶瓷工业]