Chromium(III) Iodide (CrI3) Powder and Crystals

Chromium(III) iodide (also known as chromium triiodide CrI₃) belongs to a rare group of layered transition metal trichalcogenides (TMTCs) ferromagnetic semiconductors. Unlike chromium trichloride which shows a 2D-Heisenberg magnetic behaviour, CrI₃ exhibits stronger magnetic anisotropy promoting a 3D magnetic characteristic with larger van der Waals gap thus smaller cleavage energy.

The magnetic properties of CrI₃ are the layer thickness and stacking order dependent. Bulk CrI₃ is ferromagnetic (FM) with a Curie temperature of 61 K and a rhombohedral layer stacking, while few-layer CrI₃ has a layered antiferromagnetic (AFM) phase with a lower ordering temperature of 45 K and a monoclinic stacking.

Changing the spin direction of CrI₃ via an external field can significantly alter the electronic band structures, including a direct-to-indirect bandgap transition, Fermi surface and topological electronic states modification. Direct-to-indirect bandgap transition can be used to develop magneto-optoelectronic device where the photoconductivity can be switched by an external magnetic field.

We supply low price chromium(III) iodide in several different forms for a range of applications.

Chromium(III) Iodide Powder

Can be used for preparation of chromium(III) iodide nanoplates and ultrathin films

Sold by weight

≥99.995% purity

From £460

Chromium(III) Iodide Crystals by Size

Can be used to produce single or few-layer chromium(III) iodide sheets via mechanical or liquid exfoliation

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

≥99.999% purity

From £480

*Typical representative size, areas/dimensions may vary

Bulk single chromium(III) iodide crystal is most commonly used as sources from which single or few-layer sheets can be obtained via either mechanical or liquid exfoliation. 

Platinum FET Test Chips for 2D Materials

• Affordable
• World-Wide Shipping
• Dual Channel Electrodes

Buy Online £180

Order Now

Chromium(III) iodide powder can also be used to prepare CrI₃ nanosheets and nanoparticles by liquid-exfoliation (normally assisted by sonication). 

Key Product Data

• High purity, low price CrI₃
• Available as a powder or as individual crystals
• Can be used to produce single or few-layer sheets
• Free worldwide shipping on qualifying orders

Structure of Chromium(III) Iodide

Single crystals of chromium(III) iodide is a layered and easily cleavable insulating ferromagnet with Curie temperature of 61 K. The structure at low temperature is rhombohedral (R3, BiI₃ -type) and the high temperature structure is monoclinic (C2/m, AlCl₃ -type).

The Pristine monolayer CrI₃ exhibits a small trigonal distortion of the CrI₆ octahedron, with the edge-shared CrI₆ octahedra forming a honeycomb lattice of six Cr atoms.

Properties of Chromium(III) Iodide

After exfoliation of crystals or powder, chromium(III) iodide typically has the following properties:

• CrI₃ exhibits strong magnetic anisotropy.
• Few-layer CrI₃ has a layered antiferromagnetic (AFM) phase with a lower ordering temperature of 45 K and a monoclinic stacking.
• Monolayer CrI₃ has been confirmed to be an intrinsic 2D Ising ferromagnetic (FM) material with a suitable band gap of about 1.2 eV.
• The ferromagnetic and antiferromagnetic states can be switched on and off by changing the external gate voltage.

Chromium(III) Iodide Applications

Chromium(III) iodide single crystals can be used to prepare monolayer and few-layer CrI₃ by mechanical or liquid exfoliation. Chromium(III) iodide powder is suitable for liquid chemical exfoliation to prepare CrI₃ nanosheets and nanoparticles down to few-layer films. 

2D CrI₃ is a promising candidate for the van der Waals bonded ferromagnetic devices since its ferromagnetism can be maintained upon exfoliating of bulk crystals down to its single layer.

Being a ferromagnetic semiconductors exhibiting stronger magnetic anisotropy, Layered 2D CrI₃ is predicted to have many potential applications such as magnetoresistance, magnetic photo-galvanic and magneto–optical effects. With large out-of-plane magnetic anisotropy energy and strong magneto-optical effects in these single-spin ferromagnetic semiconducting ultrathin films, CrI₃ finds applications in high density semiconductor magneto–optical and low-power spintronic nanodevices.

Intercalated chromium(III)) iodide with Li ions can not only tune the semiconducting ultrathin CrI₃ into half-metallic, but can also largely improve the Curie temperature (T_C) and the magnetic moment simultaneously. Half-metallicity and ferromagnetism are rather robust, dependent of neither the concentration of Li ions adsorbed, nor the layer thickness of CrI₃. Self-intercalation with either Cr or I atoms can induce the double exchange effect and significantly strengthen the interlayer ferromagnetic coupling for potential electronic and spintronic applications.

Processing Chromium Iodide

Viscoelastic transfer using PDMS

Literature and Reviews

• Layer-dependent Ferromagnetism in a van der Waals Crystal down to the Monolayer Limit, B. Huang et al., Nature 546, 270–273 (2017), DOI: 10.1038/nature22391.
• On the origin of magnetic anisotropy in two dimensional CrI3, J. Lado et al., 2D Mater. 4, 035002 (2017); DOI: 10.1088/2053-1583/aa75ed.
• Critical behavior of two-dimensional intrinsically ferromagnetic semiconductor CrI3, G. Lin et al., Appl. Phys. Lett. 112, 072405 (2018); DOI: 10.1063/1.5019286.
• Spin direction controlled electronic band structure in two dimensional ferromagnetic CrI3, P. Jiang et al., Nano Lett., 18, 6, 3844–3849 (2018); DOI: 10.1021/acs.nanolett.8b01125.
• Lattice dynamics and phase transition in CrI3 single crystals, S. Djurdjic-Mijin et al., Phys. Rev. B, 98, 104307 (2018); DOI: 10.1103/PhysRevB.98.104307.
• Stacking-Dependent Magnetism in Bilayer CrI3, N. Sivadas et al., Nano Lett., 18, 12, 7658–7664 (2018); DOI: 10.1021/acs.nanolett.8b03321.
• Control of magnetism in bilayer CrI3 by an external electric field, E. Morell et al., 2D Materials 6(2), 025020 (2019); DOI:10.1088/2053-1583/ab04fb.
• Pressure-controlled interlayer magnetism in atomically thin CrI3, T. Li et al., Nat. Mater. 18, 1303–1308 (2019); DOI: 10.1038/s41563-019-0506-1.
• Strain-induced phase transition in CrI3 bilayers, A. Leon et al., 2D Mater. 7, 035008 (2020); DOI: 10.1088/2053-1583/ab8268.
• Coexistence of Magnetic Orders in Two-Dimensional Magnet CrI3, B. Niu et al., Nano Lett., 20, 1, 553–558 (2020); DOI: 10.1021/acs.nanolett.9b04282.
• Direct observation of 2D magnons in atomically thin CrI3, J. Cenker et al., Nat. Phys. 17, 20–25 (2021), DOI: 10.1038/s41567-020-0999-1.
• Systematic Study of Monolayer to Trilayer CrI3: Stacking Sequence Dependence of Electronic Structure and Magnetism, D. Wang et al., J. Phys. Chem. C, 125, 18467−18473 (2021); DOI: 10.1021/acs.jpcc.1c04311.
• Strain-tunable magnetic and electronic properties of monolayer CrI3, Z. Wu et al., Phys. Chem. Chem. Phys., 21, 7750 (2019); DOI: 10.1039/c8cp07067a.
• Half-metallicity and enhanced ferromagnetism in Li-adsorbed ultrathin chromium triiodide, Y. Guo et al., J. Mater. Chem. C, 6, 5716 (2018); DOI: 10.1039/c8tc01302k.