Telluride

The first commercial vdW Tellurium (Bulk trigonal phase) crystals. Layered tellurium crystals have been synthesized in perfectly vdW order through flux zone growth technique. The crystal has 99.9999% (6N) rated purity and has been crystalized in perfect atomic order. Layered tellurium (Te) has a trigonal crystal lattice (see product images) in which individual helical chains of Te atoms are stacked together by van der Waals type bonds and spiral around axes parallel to the [0001] direction at the center and corners of the hexagonal elementary cell [1-2]. Tellurene exhibits a tunable bandgap varying from nearly direct 0.31 eV (bulk) to indirect 1.17 eV (2L) and direct at 1.3 eV (1L) [3]. It has four (two) complex, highly anisotropic and layer-dependent hole (electron) pockets in the first Brillouin zone with an extraordinarily high hole mobility reaching up to theoretical ∼1E5 cm2/Vs value [1-3]. 

Physical size ~1cm or larger; 

Raman spectrum collected from Tellurene crystals under 532 nm laser excitation

XRD data collected from tellurene crystals

Note: This product is same as tellurene material. While material itself is perfectly crystallized in trigonal form (weakly coupled Te chains are present), it is inherently harder to exfoliate in comparison to graphene or MoS2. For best results, we recommend using strongly adhesive tapes or liquid exfoliation technique. 

Related references

[1] "Two-dimensional tellurium" Nature 552, 40-41 (2017) [Page link]

[2] "Large-area solution-grown 2D tellurene for air-stable, high-performance field-effect transistors"; arXiv:1704.06202 [Page link]

[3] "Few-layer Tellurium: one-dimensional-like layered elementary semiconductor with striking physical properties" ; https://doi.org/10.1016/j.scib.2018.01.010 [Page link]