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Product Code M2145C1-1g
Price $473 ex. VAT

Low price, high purity 2D metal tantalum diselenide powder and crystals

For the development of next-generation electronics, optoelectronics, and nanotechnology


Technical Data | MSDS | Structure | Literature and Reviews | Related Products | Resources and Support


Tantalum diselenide (2H-TaSe2), CAS number 12039-55-3, is a layered transition metal dichalcogenide (TMDC) that possesses metallic property with charge density wave characteristics, coupled with strong light absorption and emission due to energy separated bands. Tantalum diselenide (TaSe2) is a family member of Group VB transition metal dichalcogenides (TMDCs). Group VB is one of the most heavily-studied group of TMDCs due to their diverse permutations of stable compounds and electronic behaviour.

High Purity Tantalum Diselenide

High Purity

≥99.999% TaSe2 Crystal

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Low Cost Tantalum Diselenide

Low Cost

Low Cost TaSe2

Different Forms of Tantalum Diselenide

Powder & Crystal

Different Forms of Tantalum Diselenide

2H-TaSe2 is a metal (or semi-metal) with no band gap. In its bulk form, 2H-TaSe2 showed two-step charge-density-wave (CDW) transitions. The first transition from the metallic phase to the incommensurate charge-density-wave (ICDW) phase was at 123K, The next was a commensurate charge-density-wave (CCDW) phase transition at 90K, followed by a superconducting transition at low temperature (Tc ∼ 0.2 K).

1T-TaSe2, however, is metallic in the bulk structure but insulating in a single-layer. It has thickness- and temperature-dependent properties in the commensurate charge density wave (CCDW) accompanied by a periodic lattice distortion (PLD).

The 2H phase is stable at room temperature while the 1T phase is stable at 800 °C.

We supply low price tantalum diselenide in several different forms for a range of applications.

Tantalum diselenide powder

Tantalum Diselenide Powder

Can be used for preparation of tantalum diselenide nanoplates and ultrathin films

Sold by weight

≥99.995% purity

From £350

Tantalum diselenide crystals by size

Tantalum Diselenide Crystals by Size

Can be used to produce single or few-layer tantalum diselenide sheets via mechanical or liquid exfoliation

Small (≥10 mm2) or medium (≥25 mm2) crystals available*

≥99.999% purity

From £520

*Typical representative size, areas/dimensions may vary

Bulk single tantalum diselenide crystal is most commonly used as sources from which single or few-layer sheets can be obtained via either mechanical or liquid exfoliation.

Tantalum diselenide powder can also be used to prepare TaSe2 nanosheets and nanoparticles by liquid-exfoliation (normally assisted by sonication). Lithium, Sodium, Cesium, Iron and Rubidium ions can be intercalated between the layers tantalum diselenide especially for changes in both superconducting and CDW properties.

Technical Data

CAS Number 12039-55-3
Chemical Formula TaSe2
Molecular Weight 338.87 g/mol
Bandgap N/A
Preparation Synthetic - Chemical Vapour Transport (CVT)
Structure Hexagonal (2H)
Electronic Properties 2D CDW materials
Melting Point >1,300 °C
Colour Dark brown
Synonyms Tantalum(IV) selenide, Bis(selanylidene)tantalum
Classification / Family Transition metal dichalcogenides (TMDCs), 2D charge density wave (CDW) materials, Nano-electronics, Nano-photonics, Superconductivity, Photovoltaic, Materials science

Product Details

Form Purity
Powder ≥99.995%
Crystal ≥99.999%

Pricing Table

Product Code Form Size/Weight* Price
M2145C1 Powder 1 g £350
M2145A10 Crystal Small (≥10 mm2) £520 ea.
M2145A25 Crystal Medium (≥25 mm2) £850 ea.

*Typical representative size, areas/dimensions may vary

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MSDS Documents


Tantalum diselenide powder MSDSTantalum diselenide powder

Tantalum diselenide crystal MSDSTantalum diselenide crystal

Structure of Tantalum Diselenide


Tantalum diselenide (TaSe2), with a crystal structure of hexagonal symmetry. The crystal structures of TaSe2 contain Ta in trigonal prismatic coordination within Se-Ta-Se layers. The weak interlayer van der Waals (vdW) bonding leads to various TaSe2 polytypes, which differ simply in the relative orientations of the layers and their stacking arrangements.

Hexagonally coordinated 2H-TaSe2 polytype is the most stable phase at room temperature in bulk while 1T-TaSe2 phase consists of a layer of Ta atoms sandwiched between two layers of Se atoms in an octahedral coordination.

TaSe2 crystal sctructure
Top and side view of single-layer tantalum diselenide (2H-TaSe2)

Literature and Reviews


  • All-metallic electrically gated 2H-TaSe2 thin-film switches and logic circuits, J. Renteria et al., J. Appl. Phys., 115, 034305 (2014); doi: 10.1063/1.4862336.
  • Phonon and thermal properties of exfoliated TaSe2 thin films, Z. Yan et al.,
    J. Appl. Phys., 114, 204301 (2013); 10.1063/1.4833250.
  • Observation of charge density waves in free-standing 1T-TaSe2 monolayers by transmission electron microscopy, P. C. Börner et al., Appl. Phys. Lett. 113, 173103 (2018); doi: 10.1063/1.5052722.

We stock a wide range of 2D materials available to purchase online. Please contact us if you cannot find what you are looking for.

Resources and Support


Viscoelastic Transfer of 2D Material Using PDMS

Viscoelastic transfer using polydimethylsiloxane (PDMS) stamps is one of the methods used for the deterministic placement of 2D materials and the fabrication of van der Waals heterostructures. It relies on the viscoelasticity of PDMS, which behaves as an elastic solid on short time scales, but as a viscous fluid on long time scales.

Learn more...
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