发表机构
University of Rostock; Pidstryhach Institute for applied problems of mechanics and mathematics of NAS of Ukraine; Center for Interdisciplinary Electron Microscopy (ELMI-MV), Department “Life, Light & Matter”, University of Rostock（罗斯托克大学; 乌克兰国家科学院普季里哈赫应用力学与数学研究所; 罗斯托克大学生·光·物质学院跨学科电子显微镜中心）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
该研究开发了无膦胶体合成方法，实现Bi2Te3、BiTe和Bi4Te5纳米片的相选择性制备，并通过原位加热揭示其热稳定性与相变机制，为热电和拓扑应用提供基础。
AI 中文摘要
碲化铋（Bi2Te3）是一种典型的V-VI族半导体，在热电和拓扑应用中备受关注；然而，在铋-碲同系物系列中，相选择性合成和热稳定性仍知之甚少。我们报道了一种简便且无膦的胶体合成方法，用于相选择性合成具有明确六边形形貌的Bi2Te3、BiTe和Bi4Te5纳米片。通过控制前驱体化学和反应温度，我们在(Bi2)m(Bi2Te3)n同系物系列中实现了不同相的选择性形成。基于原位加热研究，BiTe和Bi4Te5纳米片在约340°C时转变为Bi2Te3，随后在更高温度下，在真空或空气中优先发生Te升华或氧化。我们讨论了这些相变的可能机制。EDS分析和STEM图像的FFT分析为温度依赖的组成和结构变化提供了直接证据，并突出了这些相之间的密切热关系。这些结果不仅推进了对纳米尺度铋-碲化物相稳定性和热行为的基本理解，而且为理解相关同系物系列中的结构演化建立了框架，为其未来在热电、自旋电子和拓扑系统中的潜在应用提供了见解。
英文摘要
Bismuth telluride (Bi2Te3) is a prototypical V-VI semiconductor of interest for both thermoelectric and topological applications; however, phase-selective synthesis and thermal stability across the bismuth-telluride homologous series remain poorly understood. We report a facile and phosphine-free colloidal synthesis approach for a phase-selective synthesis of Bi2Te3, BiTe, and Bi4Te5 nanosheets with well-defined hexagonal morphology. By controlling precursor chemistry and reaction temperature, we achieved the selective formation of different phases within the (Bi2)m(Bi2Te3)n homologous series. Based on in situ heating studies, BiTe and Bi4Te5 nanosheets transform into Bi2Te3 at about 340 degree C, followed by preferential Te sublimation under vacuum or oxidation in air at higher temperatures. We discuss plausible mechanisms for these phase transformations. EDS analysis and FFT analysis of STEM images provide direct evidence for the temperature-dependent compositional and structural changes and highlight the close thermal relationship among these phases. These results not only advance fundamental understanding of phase stability and thermal behavior in bismuth-tellurides at the nanoscale but also establish a framework for understanding structural evolution in related homologous series, providing insights into their potential future applications in thermoelectric, spintronic, and topological systems.
Comments32 pages, 6 figures
Journal refACS Nano 20 (2026) 20857
