~ 1.1 eV (direct)
||Rhenium selenide, Bis(selanylidene)rhenium
|Classification / Family
Transition metal dichalcogenides (TMDCs), 2D semiconductor materials, Nano-electronics, Nano-photonics, Photovoltaic, Materials science
||Synthetic - chemical vapour transport (CVT)
One of the striking physical properties of rhenium diselenide (ReSe2) is that it has a stable distorted 1T phase (1T-ReSe2) in which the underlying 1D chain arrangement of Re4 parallelograms leads to a strong in-plane anisotropy. The structural distortion causes weaker interlayer coupling, which makes its bulk material behave electronically and vibrationally like decoupled monolayers.
Due to its distorted structure (like its twin ReS2), ReSe2 has also proven to exhibit dramatic spatial-anisotropy optical response, making it possible for applications in conceptual anisotropic optoelectronic and nanomechanical devices.
ReSe2 devices exhibit an outstanding photoresponse to near-infrared light and field-effect transistors (FETs). Employing ReSe2 shows a p-type conduction characteristic with a current ON/OFF ratio of up to 105 and a hole-carrier mobility of 0.98 cm2V-1s-1.
Rhenium diselenide exhibits a low-symmetry crystal lattice due to its distorted structure caused by the parallel arrangement of Re atoms. This results in anisotropic electrical and optical properties, which is what sparked the rise of ReSe2 applications in polarisation-sensitive photodetectors and integrated polarisation controllers.
ReSe2 has also a wide range of applications including strain sensors, stretchable electrodes, and flexible FETs, solar cells, and other photonic devices.
Rhenium diselenide powder is obtained via the CVT method, with a purity in excess of 99.995% achieved.
ReSe2 thin-layer films are harder to fabricate than traditional TMDs (such as MoS2 and WS2.)The distorted 1T structure and weaker interlayer coupling can easily cause anisotropic and out-of-plane growth - thus, thick-flake, dendrimeric, and flower-like structures are commonly observed.
As such, high-purity rhenium diselenide powder is suitable for liquid chemical exfoliation to prepare ReSe nanosheets and nanoparticles down to few-layer films.
Literature and Reviews
Rhenium Dichalcogenides: Layered Semiconductors with Two Vertical Orientations, L. Hart et al., Nano Lett., 16, 1381−1386 (2016); DOI: 10.1021/acs.nanolett.5b04838.
Epitaxial growth of large-area and highly crystalline anisotropic ReSe2 atomic layer, F Cui et al., Nano Res., 10(8): 2732–2742 (2017); DOI 10.1007/s12274-017-1477-7.
- Tunable Ambipolar Polarization-Sensitive Photodetectors Based on High-Anisotropy ReSe2 Nanosheets, E. Zhang et al., ACS Nano, 10, 8067−8077 (2016); DOI: 10.1021/acsnano.6b04165.
Chemical Vapor Deposition Synthesis of Ultrathin Hexagonal ReSe2 Flakes for Anisotropic Raman Property and Optoelectronic Application, M. Hafeez et al., Adv. Mater., 28, 8296–8301 (2016); DOI: 10.1002/adma.201601977.
Tuning the Optical, Magnetic, and Electrical Properties of ReSe2 by
Nanoscale Strain Engineering, S. Yang et al., Nano Lett., 15, 1660−1666 (2015); DOI: 10.1021/nl504276u.
Raman Spectra of Monolayer, Few-Layer, and Bulk ReSe2: An Anisotropic Layered Semiconductor, D. Wolverson et al., ACS Nano, 8 (11), 11154–11164 (2014); DOI: 10.1021/nn5053926.
Direct synthesis and in situ characterization of monolayer parallelogrammic rhenium diselenide on gold foil, S. Jiang et al., Commun. Chem., 1, 17 (2018); DOI: 10.1038/s42004-018-0010-6.