近日，中国科学院大学周武教授研究了二维碲化钼化合物中缺碲相的捕获与编辑。2026年1月28日，《美国化学会志》发表了这一成果。

化学计量比二维材料及其异质结构的相工程调控，因各化学计量相之间热力学稳定性的显著差异而始终面临严峻挑战。

研究组提出一种动态平衡策略，用于实现钼-碲体系中缺碲多晶相的精准构筑。通过动态平衡碲空位的生成与填充，研究组驱动了沿不同路径的选择性相转变。以1T′-MoTe2为起始相，成功获得了三种不同的缺碲相：具有高密度镜像孪晶界的新型范德华结构Mo5Te8、Chevrel型非层状结构Mo3Te4以及准一维范德华结构Mo6Te6。这些相转变过程始于碲空位诱导的形核，随后通过相界处的外延模板效应，将多晶基体转化为单晶相。

通过顺序调控碲化学势，实现了原子级尖锐异质结构的按需合成，展现了原位相编辑能力。此外，研究组通过沉积钼覆盖层精确调控整个衬底上的碲空位浓度，实现了晶圆级均匀缺碲相（Mo5Te8、Mo6Te6）的合成。这种可扩展的相调控方法使相控异质结器件阵列的制备成为可能，彰显了其在相可编程电子学中的应用潜力。该研究为缺碲相与异质结构的构筑建立了一条缺陷介导的合成路径。

附：英文原文

Title: Capturing and Editing Te-Deficient Phases in Two-Dimensional Molybdenum Telluride Compound

Author: Xiaolong Xu, Shuangquan Qu, Roger Guzman, Mingzhu Xu, Bo Han, Mengting Huang, Yiming Ding, Binbin Zhang, Shibo Wang, Wenlei Fu, Yiwen Song, Shiqi Yang, Huixia Yang, Yu Zhang, Yuanxiao Ma, Ruiwen Shao, Peng Gao, Wu Zhou, Yu Ye, Yeliang Wang

Issue&Volume: January 28, 2026

Abstract: Phase engineering of stoichiometric two-dimensional materials and their heterostructures remains a formidable challenge due to the thermodynamic stability disparity among the stoichiometric phases. Here, we report a dynamic-equilibrium approach (DEA) to access Te-deficient polymorphs in the Mo–Te system. By dynamically balancing tellurium vacancy generation and refilling, we drive selective phase transitions along divergent pathways. Starting from 1T′-MoTe2, we access three distinct Te-deficient phases: a novel van der Waals (vdW) Mo5Te8 with a high density of mirror-twin boundaries, a Chevrel-type nonlayered Mo3Te4, and a quasi-1D vdW Mo6Te6. These transitions proceed through Te-vacancy-initiated nucleation, followed by epitaxial templating at phase boundaries, which transforms the polycrystalline matrix into single-crystal phases. Sequentially modulating the Te chemical potential allows for the on-demand synthesis of atomically sharp heterostructures, demonstrating in situ phase editing. Moreover, we achieved wafer-scale synthesis of uniform Te-deficient phases (Mo5Te8, Mo6Te6) by depositing a Mo capping layer to precisely regulate Te vacancy concentrations across the entire substrate. This scalable control enables the fabrication of phase-controlled heterostructure device arrays, underscoring their potential for phase-programmable electronics. This work establishes a defect-mediated pathway to Te-deficient phases and heterostructures.

DOI: 10.1021/jacs.5c19547

Source: https://pubs.acs.org/doi/abs/10.1021/jacs.5c19547