Thallium

CAS 7440-28-0TlMetal & Ceramic Science

Thallium (CAS 7440-28-0, Tl) is a soft, grey, metallic element with a high density and a melting point of 303°C. Known for its extreme toxicity, thallium's primary industrial applications are limited, often serving as a component in specialized alloys, optical glass, and as a precursor in the synthesis of certain inorganic compounds. Its unique physical properties are leveraged in niche scientific and industrial processes.

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Thallium (Tl) — chemical element, CAS 7440-28-0; Materials Science, fine chemical supplied by Tech Serve Solutions

Materials ScienceMetal and Ceramic ScienceMetalsThallium

01 /Applications

Optical Glass Manufacturing

Thallium compounds are used to increase the refractive index and dispersion of optical glass, enabling the production of specialized lenses and optical instruments requiring high performance. This application leverages thallium's high atomic number and density.

Alloy Component

Due to its low melting point, thallium is used in alloys for specific applications, such as low-melting point solders and specialized metal mixtures. These alloys can find use in temperature-sensitive applications or where specific thermal expansion properties are needed.

Semiconductor Research

Thallium-based compounds have been investigated for their potential in semiconductor applications, particularly in infrared detectors and thermoelectric materials. Its electronic properties make it a subject of research in advanced materials science.

Chemical Synthesis Precursor

Thallium serves as a starting material for the synthesis of various inorganic thallium salts and compounds. These compounds may then be used in other industrial processes or laboratory research.

02 /Properties

Molecular weight	204.38
Empirical formula	Tl
Assay	99.99% trace metals basis
Form	granular
Boiling point	1457 °C(lit.)
Melting point	303 °C(lit.)

03 /Safety & handling

GHS hazard pictogram: Toxic (GHS06) — Toxic

GHS hazard pictogram: Health hazard (GHS08) — Health hazard

Danger

Hazard statements

H300Fatal if swallowed
H330Fatal if inhaled
H373May cause damage to organs through prolonged exposure
H413May cause long-lasting harmful effects to aquatic life

Precautionary statements

P260Do not breathe dust, fume, gas, mist, vapours or spray
P264Wash thoroughly after handling
P284Wear respiratory protection
P301IF SWALLOWED
P310Immediately call a POISON CENTER or doctor

Protective equipment	Eyeshields, Faceshields, full-face particle respirator type N100 (US), Gloves, respirator cartridge type N100 (US), type P1 (EN143) respirator filter, type P3 (EN 143) respirator cartridges
Transport (UN / ADR)	UN 3288 6.1 / PGII
Water hazard class (WGK, DE)	3
Hazard codes (EU)	T+
Risk statements (R)	26/28-33-53
Safety statements (S)	13-28-45-61

Hazard information is provided for guidance. Always consult the product Safety Data Sheet (SDS), available on request, before handling.

04 /Identifiers & registry

CAS number

7440-28-0

MDL number

MFCD00134063

PubChem substance

24856794

05 /Additional specifications

Resistivity	18 μΩ-cm, 20°C

06 /Quality & supply

Documentation

Every batch ships with a Certificate of Analysis covering assay, identity and purity; the grade is confirmed against your enquiry. Safety Data Sheets and technical data sheets are available on request.

Supply & logistics

Samples for technical evaluation; bulk MOQ by grade and packaging. In-stock material ships in 7–10 working days, worldwide, with full export documentation.

07 /Frequently asked questions

What is Thallium used for?

Thallium's primary uses are in specialized applications such as optical glass, certain alloys, and as a precursor in chemical synthesis, although its extreme toxicity limits widespread application.

What is the CAS number and formula for Thallium?

The CAS number for Thallium is 7440-28-0 and its chemical formula is Tl.

What grade and purity does Tech Serve Solutions supply?

Tech Serve Solutions supplies Thallium with an assay of 99.99% on a trace metals basis. We do not represent this product as USP, BP, or EP grade.

How should Thallium be handled?

Thallium is extremely toxic and requires strict handling procedures. Use appropriate personal protective equipment, including eyeshields, face shields, full-face particle respirators (N100), gloves, and P3 particulate respirator filters. Handle only in well-ventilated areas or under a fume hood.

Is Thallium a controlled substance?

Thallium compounds are highly toxic and subject to strict regulations. It is classified under UN 3288, hazard class 6.1, Packing Group II.

How is Thallium shipped or exported?

Thallium is shipped as a hazardous material under UN 3288, class 6.1, Packing Group II, adhering to all international shipping and export regulations for toxic substances.

How can I request a quote or sample?

Please contact our sales team through the website or by phone to request a quote or sample of Thallium. Provide your contact details and the quantity required.