Abstract Transition metal dichalcogenides (TMDs) are known for their layered structure and tunable functional properties. However, a unified understanding on other transition metal chalcogenides (i.e. M 2 X) is still lacking. Here, the relatively new class of copper-based chalcogenides Cu 2 X (X = Te, Se, S) is thoroughly reported. Cu 2 X are synthesized by an unusual vapor–liquid assisted growth on a Al 2 O 3 /Cu/W stack. Liquid copper plays a significant role in synthesizing these layered systems, and sapphire assists with lateral growth and exfoliation. Similar to traditional TMDs, thickness dependent phonon signatures are observed, and high-resolution atomic images reveal the single phase Cu 2 Te that prefers to grow in lattice-matched layers. Charge transport measurements indicate a metallic nature at room temperature with a transition to a semiconducting nature at low temperatures accompanied by a phase transition, in agreement with band structure calculations. These findings establish a fundamental understanding and thrust Cu 2 Te as a flexible candidate for wide applications from photovoltaics and sensors to nanoelectronics.
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Effects of trimethylaluminum vapor pressure and exposure time on inorganic loading in vapor phase infiltrated PIM-1 polymer membranes
- Award ID(s):
- 1921873
- NSF-PAR ID:
- 10353062
- Date Published:
- Journal Name:
- Materials Chemistry and Physics
- Volume:
- 290
- Issue:
- C
- ISSN:
- 0254-0584
- Page Range / eLocation ID:
- 126577
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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