Theoretical and experimental investigations of various exfoliated samples taken from layered In4Se3crystals are performed. In spite of the ionic character of interlayer interactions in In4Se3and hence much higher calculated cleavage energies compared to graphite, it is possible to produce few‐nanometer‐thick flakes of In4Se3by mechanical exfoliation of its bulk crystals. The In4Se3flakes exfoliated on Si/SiO2have anisotropic electronic properties and exhibit field‐effect electron mobilities of about 50 cm2 V−1 s−1at room temperature, which are comparable with other popular transition metal chalcogenide (TMC) electronic materials, such as MoS2and TiS3. In4Se3devices exhibit a visible range photoresponse on a timescale of less than 30 ms. The photoresponse depends on the polarization of the excitation light consistent with symmetry‐dependent band structure calculations for the most expected
- Award ID(s):
- 1905499
- NSF-PAR ID:
- 10424546
- Date Published:
- Journal Name:
- Journal of Materials Chemistry C
- Volume:
- 11
- Issue:
- 2
- ISSN:
- 2050-7526
- Page Range / eLocation ID:
- 609 to 615
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract ac cleavage plane. These results demonstrate that mechanical exfoliation of layered ionic In4Se3crystals is possible, while the fast anisotropic photoresponse makes In4Se3a competitive electronic material, in the TMC family, for emerging optoelectronic device applications. -
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