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Product Code M2138C1-500mg
Price $403 ex. VAT

Due to shipping restrictions this product is not available in all destinations.

Low price, high purity gallium selenide powder and crystals

Suitable for use a semiconductor, photoconductor, and in non-linear optics


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


Gallium selenide (GaSe), CAS number 12024-11-2, is a group XIII post-transitional mono-chalcogenide. Like transition metal dichalcogenides (TMDCs), it is a layered semiconductor. In gallium selenide, each individual layer consists of covalently-bonded stacks with sheets of Se ions on the top and bottom and two sheets of Ga ions in the middle.

High Purity Gallium Selenide (GaSe)

High Purity

High purity gallium selenide ≥99.995% powder

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Worldwide shipping

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Low price Gallium Selenide

Low price

Low price Gallium Selenide

powder and crystals 12024-11-2

Different Forms

Available in powder and crystals

As with other layered 2D structures like graphene, adjacent GaSe layers are bound by the weak van der Waals force. This makes it possible to peel the structure by mechanical or liquid exfoliation. The resultant ultra-thin few or single layer 2D gallium selenide nanosheets or nanoparticles have well-known nonlinear optical properties and a range of applications in areas including integrated optics, optical information communications and biology.

We supply high purity gallium selenide powder and crystals.

Gallium selenide powder

Gallium Selenide Powder

Can be used in electronic and optical devices and in the preparation of GaSe nanosheets or nanoparticles liquid chemical exfoliation or chemical vapour deposition

Available in quantities of 500 mg or 1 g

≥99.995% purity

From £310

Gallium selenide crystals

Gallium Selenide Crystals by Size

Can be used as a semiconductor, in non-linear optics, and to produce 2D monolayer and few-layer GaSe by mechanical or liquid exfoliation

Small (>10 mm2) or medium (>25 mm2) available*

≥99.999% purity

From £520

*Typical representative size, areas/dimensions may vary

Technical Data

CAS Number 12024-11-2
Chemical Formula GaSe
Molecular Weight 148.69 g/mol
Bandgap ~2.1 eV (indirect)
Crystal Structure Hexagonal
Electrical Properties 2D semiconductor
Synonyms Gallium(II) selenide, Selanylidenegallium
Classification / Family Transition metal dichalcogenides (TMMCs), 2D semiconductor materials, Nano-electronics, Nano-photonics, Photovoltaic, Materials science
Preparation Synthetic - Chemical Vapour Transport (CVT)
Colour Dark copper

Product Details

Form Purity
Powder ≥99.995%
Crystal ≥99.999%

Pricing Table

Product Code Form Size/Weight* Price
M2138C1 Powder 500 mg £310
M2138C1 Powder 1 g £480
M2138A10 Crystal Small (≥10 mm2) £520 ea.
M2138A25 Crystal Medium (≥25 mm2) £850 ea.

*typical representative size, areas/dimensions may vary.

MSDS Documents


Gallium selenide powder MSDSGallium selenide powder

Gallium selenide crystal MSDSGallium selenide crystal

Structure of Bulk and 2D Gallium Selenide


The hexagonal-layered structure of gallium selenide is similar to the structure of gallium sulfide (GaS). Each individual layer consists of four sheets of atoms in the sequence 'Se-Ga-Ga-Se'.

Each Ga atom is tetragonally-coordinated to three Se atoms and one Ga atom. Strong bonding between two sheets within the individual layer is thought to be covalent in nature, with some ionic contribution.

Gallium selenide crystal structure
The crystal structure of hexagonal gallium selenide (GaSe)

Depending on the sequence of stacking, the three most important classifications are β-GaSe, ε-GaSe, and γ-GaSe phases. Both β-GaSe and ε-GaSe are 2H hexagonal structured.

Literature and Reviews


Gallium Selenide Powder in Literature

  • Layer-Dependent Nonlinear Optical Properties and Stability of NonCentrosymmetric Modification in Few-Layer GaSe Sheets, Angew. Chem. Int. Ed., 54, 1185 –1189 (2015); DOI: 10.1002/anie.201409837.
  • Investigation of Second- and Third-Harmonic Generation in Few-Layer Gallium Selenide by Multiphoton Microscopy, L. Karvonen et al., Sci. Rep., 5:10334 (2015); DOI: 10.1038/srep10334.
  • Highly sensitive phototransistor based on GaSe nanosheets, H. Huang et al., Appl. Phys. Lett. 107, 143112 (2015); doi: 10.1063/1.4933034.

Gallium Selenide Crystals in Literature

  • Multifunctional 2D- Materials: Gallium Selenide, N. B. Singh et al., Mater. Today: Proceedings 4, 5471–5477 (2017); dio: 10.1016/j.matpr.2017.06.002.
  • Effective Nonlinear GaSe Crystal Optical Properties and Applications, K. R. Allakhverdiev et al., Laser Phys., 19 (5), 1092–1104 (2009); DOI: 10.1134/S1054660X09050375.
  • Copper indium gallium selenide based solar cells – a review, J. Ramanujam et al., Energy Environ. Sci., 10, 1306 (2017); DOI: 10.1039/c7ee00826k.


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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