α-Cu2Se的显微缺陷结构

α-Cu₂Se的显微缺陷结构

王正洲,白  辉,吴劲松^*

（武汉理工大学1.材料复合新技术国家重点实验室, 2.纳微结构研究中心, 湖北武汉430070）

摘  要  本文利用球差校正电镜对Cu₂Se低温α相的显微缺陷结构进行精细表征。α-Cu₂Se呈层状特征，其中Se构成了刚性亚晶格，Cu离子有序填充于{111}_c晶面之间形成了交替分布的富Cu层和贫Cu层。层间滑移是导致超结构出现的主要原因。在Cu₂Se从高温β相到低温α相的结构转变过程中，由于对称性破缺和Se刚性亚晶格的保留，Cu离子在不同区域的有序性差异使得α-Cu₂Se中存在大量共格连接的畴结构。实验结果有助于更全面地理解α-Cu₂Se的显微缺陷结构。

关键词  a-Cu₂Se；球差校正电镜；Cu离子有序性；取向畴

中图分类号：TG115.21⁺5.3；Q766 文献标识码：A    doi:10.3969/j.issn.1000-6281.2023.04.005

Microscopic defectstructurein α-Cu₂Se

WANG Zheng-zhou, BAI Hui, WU Jin-song *

(Wuhan University of Technology 1. State Key Laboratory of Advanced Technology for Materials Synthesis and Processing,2. Nanostructure Research Center, Wuhan Hubei 430070, China)

Abstract    The microscopic defect structure in a Cu₂Se low-temperature phase was characterized by spherical aberration correction transmission electron microscopy. a-Cu₂Sehas a layered structure, in which Se forms a rigid sublattice, and Cu ions are orderly filled between {111}_c crystal planes, forming the alternately distributed Cu-rich layers and Cu-deficient layers. The interlayer slip is the main cause of superstructure. During the structural transition of Cu₂Se from bphase to a phase, the different ordering of Cu ions in different regions generates a large number of coherently connected domain structures in a-Cu₂Sedue to the symmetry breaking and the retention of Se rigid sublattice. The experimental results contribute to a more comprehensive understanding of the microscopic defect structure in a-Cu₂Se.

Keywords   a-Cu₂Se；spherical aberration correction transmission electron microscopy；Cu ion ordering；oriented domain

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