Atomic Imaging of 2D Transition Metal Diiodides
Year: 2026
Type: article
Abstract: are an emerging class of 2D magnets exhibiting rich and diverse magnetic behavior, but their study at the monolayer limit has been severely hindered by fabrication challenges due to their air-sensitivity. Here, we introduce a polymer-free method for clean, rapid, and high-yield assembly of hermetically encapsulated suspended samples of air-sensitive monolayers. Applied to diiodides, it enables atomic resolution characterization of thin samples down to the monolayer limit using transmission electron microscopy. Our imaging, combined with complementary first-principles calculations, reveals an unusually small energy barrier between alternate stable stacking polytypes in few-layer films, enabling extrinsic control of the stacking phase. We also observe stable isolated iodine vacancies that do not aggregate to form extended structures and identify and verify the stability of the various edge configurations of thin samples. These results establish the structural characteristics of these materials in the thin limit and more broadly demonstrate the utility of our transfer platform for creating atomically clean suspended van der Waals heterostructures.
Source: ACS Nano
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: green
Awards: G116007080, G116049213, G1713080207, Quantum and Many Body Physics Enabled by Advanced Semiconductor Nanotechnology, G2286066951, G434337789, G439009189, Sir Henry Royce Institute - Manchester and NNL Equipment, G4589224585, G4851265500, Elucidation of membrane interface chemistry for electro-chemical processes, Correlative Mapping of Crystal Orientation and Chemistry at the Nanoscale, Two-dimensional quantum materials and devices for scalable integrated photonic circuits, G5790051442, Sir Henry Royce Institute - Manchester Build, G58575188, Supporting World-Class Labs at the University of Manchester, The Royce: Capitalising on the investment, Van der Waals Heterostructures of 2D Materials, Precision Dry Etching of 2D Materials: 2DETCH, G708391930, Nanoscale Advanced Materials Engineering, G7526182273, Next Generation Multi-Dimensional X-Ray Imaging, Sir Henry Royce InsStitute - recurrent grant, G87373762, Quantum Materials by Twistronics
OpenAlex ID: W7124216595