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Platinum, palladium and nickel dichalcogenides

PtSe₂, PdSe₂, PtS₂, PtTe₂, PdTe₂, NiTe₂

Also called PtSe₂, PdSe₂, PtTe₂, PdTe₂, NiTe₂, noble-metal dichalcogenides

van der Waals crystal depends on form

Semiconductors that turn into metals as they get thicker. The transition happens at just a few layers, so one film can act as conductor or semiconductor depending on local thickness. PtSe2 can also be grown at temperatures low enough to deposit onto finished silicon chips, which makes it one of the more realistic candidates for industrial integration. The tellurides are metals with a different appeal: their bands cross in tilted, ‘type-II’ Dirac cones, and PdTe2 is also a superconductor.

Crystal structure

  • Pt
  • Se
Cell
Hexagonal, a = 3.73 Å
Atoms per cell
3
Pt–Se bond
2.51 Å
Height
2.57 Å between the outer atom centres
Each platinum atom sits inside an octahedron of six selenium atoms, and the upper and lower selenium planes are staggered rather than stacked one above the other – the 1T arrangement, which gives the layer a centre of inversion. A single layer is a semiconductor; adding layers closes the gap until the bulk crystal is a semimetal. One layer of bulk 1T-PtSe2 (Furuseth, Kjekshus and Selte, Acta Chemica Scandinavica 19, 257, 1965; COD 1537202): a = 3.73 Å, selenium planes 1.28 Å above and below the Pt plane.

Key properties

  • Thickness-driven semiconductor-to-semimetal transition in PtSe2 at roughly two to three layers
  • Wafer-scale films by selenisation of platinum at ~400 °C – within back-end-of-line thermal budgets
  • High air stability compared with most TMDCs
  • PdSe2: pentagonal, strongly anisotropic layers with electron mobility around 150 cm2/(V·s) in few-layer devices
  • PtTe2, PdTe2 and NiTe2 host type-II Dirac fermions; in NiTe2 the Dirac point lies close to the Fermi level
  • PdTe2 is a superconductor below ~1.7 K

How it is made

  • Thermally assisted selenisation of pre-deposited Pt films at ~400 °C – wafer-scale but polycrystalline
  • Direct selenisation of Pt(111) single crystals for monolayer spectroscopy
  • Vapour-transport or flux growth and exfoliation; CVD
  • Ditelluride crystals by vapour transport or flux growth; CVD growth of thin PtTe2

Uses, and how close they are

  • Sensors and photodetectors grown directly on silicon back-end-of-lineprototype
  • Mid-infrared photodetectorslab
  • Gas and pressure sensorsprototype

Readiness runs lab → prototype → pilot → deployed.

Open problems

  1. Can low-temperature PtSe2 films become crystalline enough to rival exfoliated flakes in mobility?
  2. Where exactly does the semiconductor–semimetal transition occur, and how do defects and interlayer coupling shift it?
  3. Is the cost of platinum acceptable for any high-volume application?
  4. Do the ditellurides keep their type-II Dirac bands in few-layer flakes, and can PdTe2’s superconductivity be made topological?

Going deeper

Short notes for specialists. Choose a lens in the header and yours comes first.

For theoreticians · your lens

Strong interlayer coupling through Se p_z orbitals drives the thickness-dependent gap closure; dispersion corrections and spin–orbit coupling change the critical layer number, and GW is needed to place it quantitatively. PdSe2’s pentagonal layers are a test case for low-symmetry anisotropic transport. In the ditellurides the strong interlayer coupling produces tilted type-II Dirac cones along the stacking direction, protected by threefold rotation symmetry.

For experimentalists · your lens

PtSe2 Raman shows E_g near 177 cm−1 and A1g near 205 cm−1, with positions and intensity ratio changing with thickness. Because selenised films are polycrystalline, confirm layer number by AFM or cross-sectional TEM rather than Raman alone. For the ditellurides, map the Dirac points with photon-energy-dependent ARPES, because they lie at finite k_z.

For engineers · your lens

Among the most integration-friendly 2D materials: selenisation at ~400 °C is compatible with finished CMOS wafers and the films are stable. Precious-metal cost and film uniformity at wafer scale are the practical questions.

In the research tracks

Growth methods

Readiness assessments

Recent news

The newest items tagged PtSe2, PdSe2, ditellurides, from the news feed updated 5 Oct 2026.

Journal Physical Review B

Two-gap to single-gap transition and two-dome-like superconductivity in alkali-metal intercalated bilayer PdTe2

PdTe2 has been synthesized with controllable thickness down to the monolayer limit. Based on first-principles calculations within the fully anisotropic Migdal–Eliashberg framework, this work reveals that alkali-metal intercalation markedly enhances the weak superconductivity of bilay… [Phys. Rev. B 114, 144515]…

TheoryPtSe₂, PdSe₂, ditellurides
Journal Physical Review B

Vacancy-driven electronic reconstruction in monolayer PtSe2: Formation thermodynamics and charge states

Layered transition metal dichalcogenides are an important platform for two-dimensional materials, where the inevitable intrinsic defects provide new degrees of freedom for tuning their physical properties. Based on first-principles calculations, this work systematically investigates the formation en… [Phys. Rev. B 114…

TheoryPtSe₂, PdSe₂, ditellurides
Preprintnot yet peer reviewed arXiv

Vacancy-Driven Electronic Reconstruction in Monolayer PtSe2: Formation Thermodynamics and Charge States

Layered transition metal dichalcogenides are an important platform for two-dimensional materials, where the inevitable intrinsic defects provide new degrees of freedom for tuning their physical properties. Based on first-principles calculations, this work systematically investigates the formation energies, charge…

TheoryPtSe₂, PdSe₂, ditellurides
Preprintnot yet peer reviewed arXiv

Quadratic piezoelectricity from stacking-engineered interference in multilayer sliding ferroelectrics

Designing nonlinear piezoelectricity requires suppressing the linear piezoelectric coefficient without extinguishing higher-order electromechanical response, yet a general and reconfigurable route remains lacking. Here we introduce stacking-engineered piezoelectric interference as such a mechanism in multilayer sliding…

TheoryPtSe₂, PdSe₂, ditelluridesMoS₂

All 8 items tagged PtSe₂, PdSe₂, ditellurides in the news feed  ·  RSS feed for PtSe₂, PdSe₂, ditellurides

Key references

  1. Monolayer PtSe2, a new semiconducting transition-metal-dichalcogenide, epitaxially grown by direct selenization of PtWang et al. · Nano Letters 15, 4013 (2015)cited by 700doi:10.1021/acs.nanolett.5b00964
  2. High-performance hybrid electronic devices from layered PtSe2 films grown at low temperatureYim et al. · ACS Nano 10, 9550 (2016)cited by 380doi:10.1021/acsnano.6b04898
  3. PdSe2: pentagonal two-dimensional layers with high air stability for electronicsOyedele et al. · Journal of the American Chemical Society 139, 14090 (2017)cited by 771doi:10.1021/jacs.7b04865
  4. Lorentz-violating type-II Dirac fermions in transition metal dichalcogenide PtTe2Yan et al. · Nature Communications 8, 257 (2017)cited by 464doi:10.1038/s41467-017-00280-6
  5. Experimental realization of type-II Dirac fermions in a PdTe2 superconductorNoh et al. · Physical Review Letters 119, 016401 (2017)cited by 301doi:10.1103/PhysRevLett.119.016401
  6. Topological type-II Dirac fermions approaching the Fermi level in a transition metal dichalcogenide NiTe2Xu et al. · Chemistry of Materials 30, 4823 (2018)cited by 160doi:10.1021/acs.chemmater.8b02132
Transition metal dichalcogenides MoS₂ Molybdenum disulfide van der Waals crystal
type
semiconductor
thickness
~0.65 nm per layer
band gap
1.2–2.5 eV
most mature
deployed
Dry lubricant and hydrodesulfurisation catalyst (bulk MoS2) Transition metal dichalcogenides WTe₂ Tungsten ditelluride van der Waals crystal
type
depends on form
thickness
~0.7 nm per layer
most mature
lab
Topological edge-state and superconducting research devices