Dative Epitaxy of Commensurate Monocrystalline Covalent van der Waals Moiré Supercrystal

Authors

Mengying Bian, SUNY University at Buffalo
Liang Zhu, Southern University of Science and Technology, Shenzhen
Xiao Wang, Bryn Mawr College
Junho Choi, National High Magnetic Field Laboratory, Los Alamos National Laboratory
Rajesh V. Chopdekar, Advanced Light Source, Lawrence Berkeley National Laboratory
Sichen Wei, SUNY University at Buffalo
Lishu Wu, School of Physical and Mathematical Sciences, Nanyang Technological University
Chang Huai, SUNY University at Buffalo
Austin Marga, SUNY University at Buffalo
Qishuo Yang, Southern University of Science and Technology, Shenzhen
Yuguang C. Li, SUNY University at Buffalo
Fei Yao, SUNY University at Buffalo
Ting Yu, Nanyang Technological University
Scott A. Crooker National High Magnetic Field Laboratory, Los Alamos National Laboratory
Xuemei Cheng, Bryn Mawr CollegeFollow
Renat F. Sabirianov, University of Nebraska at Omaha
Shengbai Zhang, Rensselaer Polytechnic Institute
Junhao Lin, Southern University of Science and Technology, Shenzhen
Yanglong Hou, Beijing Innovation Center for Engineering Science and Advanced Technology
Hao Zeng, SUNY University at Buffalo

Document Type

Article

Version

Author's Final Manuscript

Publication Title

Advanced Materials

Publication Date

2022

Abstract

Realizing van der Waals (vdW) epitaxy in the 1980s represents a breakthrough that circumvents the stringent lattice matching and processing compatibility requirements in conventional covalent heteroepitaxy. However, due to the weak vdW interactions, there is little control over film qualities by the substrate. Typically, discrete domains with a spread of misorientation angles are formed, limiting the applicability of vdW epitaxy. Here, the epitaxial growth of monocrystalline, covalent Cr5Te8 2D crystals on monolayer vdW WSe2 by chemical vapor deposition is reported, driven by interfacial dative bond formation. The lattice of Cr5Te8, with a lateral dimension of a few tens of micrometers, is fully commensurate with that of WSe2 via 3 × 3 (Cr5Te8)/7 × 7 (WSe2) supercell matching, forming a single-crystalline moiré superlattice. This work establishes a conceptually distinct paradigm of thin-film epitaxy, termed “dative epitaxy”, which takes full advantage of covalent epitaxy with chemical bonding for fixing the atomic registry and crystal orientation, while circumventing its stringent lattice matching and processing compatibility requirements; conversely, it ensures the full flexibility of vdW epitaxy, while avoiding its poor orientation control. Cr5Te8 2D crystals grown by dative epitaxy exhibit square magnetic hysteresis, suggesting minimized interfacial defects that can serve as pinning sites.

Citation

Bian, M., Zhu, L., Wang, X., Choi, J., Chopdekar, R. V., Wei, S., Wu, L., Huai, C., Marga, A., Yang, Q., Li, Y. C., Yao, F., Yu, T., Crooker, S. A., Cheng, X. M., Sabirianov, R. F., Zhang, S., Lin, J., Hou, Y., Zeng, H., 2022. "Dative Epitaxy of Commensurate Monocrystalline Covalent van der Waals Moiré Supercrystal." Adv. Mater.: 2200117.

DOI

https://doi.org/10.1002/adma.202200117