Selenides

Few material families cover as much of the electromagnetic spectrum as the selenides. Zinc selenide optics steer 10.6 μm CO₂ laser beams, lead selenide quantum dots watch the short-wave infrared, and copper indium gallium selenide films convert sunlight into electricity at efficiencies above 23%. One chemistry — selenium bonded to metals — supports all of it.

Eata Energy provides high-purity selenide raw materials for research and industry: semiconductor-grade powders, granules and single crystals, sputtering targets for thin-film deposition, colloidal quantum dots, and CVD-grown two-dimensional crystals. Every batch is delivered with full chemical analysis, and compositions can be tuned to your specification.

High-purity selenide crystals and granules supplied by Eata Energy

What Are Selenides?

Selenides are compounds in which selenium — sitting directly below sulfur in Group 16 — carries a formal −2 charge bonded to one or more less electronegative elements. They behave much like their sulfide cousins, but with a twist that engineers care about: the heavier selenium atom narrows the band gap, raises carrier mobility, strengthens spin–orbit coupling and lowers lattice thermal conductivity. That single substitution turns ordinary semiconductors into record-breaking thermoelectrics, topological insulators and efficient thin-film solar absorbers.

Key Properties of Selenide Materials

• Extremely wide band-gap range — from roughly 0.28 eV (PbSe) up to about 2.7 eV (ZnSe), one family spans the visible, near-infrared and short-wave infrared, giving absorber and detector design unusual freedom.
• Record thermoelectric performance — single-crystal SnSe reached ZT = 2.6 at 923 K along the b-axis, and purified polycrystalline SnSe has pushed ZT to ≈3.1 at 783 K; superionic Cu₂Se delivers ZT of 1.5–2.6 in the mid-temperature range.
• Strong light absorption — CIGS and Sb₂Se₃ absorb above 10⁵ cm⁻¹, so a 1–2 μm film captures nearly the full solar spectrum, and the CIGS band gap tunes continuously from 1.0 to 1.7 eV with the In/Ga ratio.
• Infrared transparency — CVD-grown ZnSe transmits from 0.5 to 20 μm with absorption below 0.0005 cm⁻¹ at 10.6 μm, making it the standard window and lens material for high-power CO₂ lasers.
• Quantum confinement — CdSe quantum dots emit narrow, size-tunable light across 480–650 nm, while PbSe dots, with their 46 nm Bohr radius, tune absorption from 800 to 3200 nm for SWIR imaging.
• Exotic electronic phases — Bi₂Se₃ is the model three-dimensional topological insulator, MoSe₂ and WSe₂ monolayers host valley-selective physics, and FeSe superconducts, giving quantum researchers a rich playground.

Selenide Materials We Supply

Band gaps are bulk values at room temperature unless noted; ML = monolayer.

Available Forms

• Powders and nanopowders — 4N–6N purity, micron to sub-micron, passivated or dry-packed under argon
• Granules and shot — evaporation and CVD feedstock with controlled particle size
• Single crystals — Bridgman and vapor-transport-grown, oriented, for optics and fundamental research
• Sputtering and evaporation targets — binary through quaternary compositions, including CIGS stoichiometries, bonded to backing plates
• Quantum dot dispersions — CdSe and PbSe cores and core/shell structures supplied in solvent
• 2D material crystals and films — MoSe₂ and WSe₂ bulk crystals plus CVD monolayers on substrates

Applications of Selenides

Thin-Film Photovoltaics

CIGS is the flagship selenide technology in solar energy. Laboratory cells have reached a champion efficiency of 23.4%, and flexible devices grown on polymer foils exceed 22%, all from an absorber layer only 1–2 μm thick. Because the band gap tunes from 1.0 to 1.7 eV, CIGS also pairs naturally with perovskite top cells — perovskite/CIGS tandems have already passed 24% and modeled devices approach 30%. Antimony selenide is the fast-rising alternative: earth-abundant and low-toxicity, Sb₂Se₃ cells hold a certified record of 10.57%, and new homojunction designs are rapidly closing the voltage gap.

Flexible CIGS thin-film photovoltaic cell based on copper indium gallium selenide

Thermoelectric Energy Conversion

Selenides dominate modern thermoelectrics. SnSe single crystals hold the celebrated ZT = 2.6 record at 923 K, and careful purification of polycrystalline SnSe has since reached ZT ≈ 3.1 at 783 K. Superionic Cu₂Se converts mid-grade industrial heat with ZT between 1.5 and 2.6, while Ag₂Se-based films operate near room temperature at ZT around 1.2 and flex with wearable and curved-surface devices. Together they cover waste-heat recovery from exhaust piping, engine systems and process lines.

Selenide thermoelectric modules recovering waste heat from exhaust piping

Infrared Optics and High-Power Lasers

CVD zinc selenide is the workhorse of CO₂ laser optics. It transmits from 0.5 to 20 μm, absorbs less than 0.0005 cm⁻¹ at the 10.6 μm laser line, and survives continuous power densities above 15 kW/cm²; with anti-reflection coatings, transmittance tops 99.5%. The same material serves FLIR protective windows and ATR prisms for infrared spectroscopy. Further into the mid-infrared, As₂Se₃ chalcogenide glass is drawn into fibers and molded lenses that carry light well beyond the reach of silica.

Polished ZnSe optics for CO₂ laser and thermal imaging systems

Quantum Dots, Displays and Imaging

Cadmium selenide is the classic quantum dot: by simply changing particle size, its emission sweeps 480–650 nm with narrow linewidths — the physics already behind commercial QLED televisions. Lead selenide dots extend the same idea into the short-wave infrared, where their 46 nm Bohr radius allows absorption tuning from 800 to 3200 nm and solution-processed SWIR cameras are now a commercial reality. Both systems depend on precursor purity, which is exactly where controlled selenide chemistry matters.

Colloidal selenide quantum dots emitting size-tunable visible light

2D Electronics and Quantum Research

Mechanically exfoliated or CVD-grown MoSe₂ and WSe₂ monolayers are direct-gap semiconductors (about 1.5 and 1.6 eV) with strong spin–valley coupling — the platform for valleytronics, tunneling devices and single-photon emitters. Bi₂Se₃ remains the benchmark topological insulator for surface-state studies, and FeSe keeps surprising the superconductivity community. All of these experiments start from high-quality bulk crystals grown by vapor transport or flux methods, where stoichiometry control is decisive.

High-temperature tube furnace for growing selenide single crystals

Batteries and Electrocatalysis

Layered selenides are gaining ground in energy storage as well. MoSe₂ and WSe₂ accommodate sodium and potassium ions between their van der Waals gaps, making them candidate anodes for post-lithium batteries, and their edge sites catalyze the hydrogen evolution reaction. Cu₂Se serves both as a conversion electrode and as a model system for studying fast-ion transport in solids.

Why Source Selenides from Eata Energy

Purity decides performance in selenide devices — a few ppm of oxygen or halide residue can erase the advantage that motivated the material choice. Eata Energy supplies selenides at 4N–6N purity with batch-specific ICP-MS certificates, so the numbers on your datasheet match the material in your reactor.

• Consistent stoichiometry from gram-scale research orders to kilogram pilot batches
• Air- and moisture-sensitive compounds sealed under argon in ampoules or dry-packed jars
• Documented lot traceability and retained samples for every shipment
• Technical support from staff who work with chalcogenide chemistry daily

Custom Selenide Services

Need something beyond the catalog? We prepare custom compositions such as CuIn₁₋ₓGaₓSe₂ with your target In/Ga ratio, sulfur-alloyed Sb₂(S,Se)₃, and doped variants (Na-, Cl- or Br-doped) on request. Particle-size engineering, target fabrication and bonding, substrate-deposited films, and quantum dots with specified emission wavelengths are all routine projects for our team. Send us your specification — we respond with a technical proposal, not just a price list.

For Research or Industrial Raw Materials, Not For Personal Medical Use!