Tin Dioxide (SnO2) Semiconductors

Written by AZoMAug 16 2013

Topics Covered

Description
Applications
Chemical Properties
Electrical Properties
Thermal, Mechanical and Optical Properties
Safety Information

Description

Tin dioxide is an inorganic compound with the chemical formula SnO₂. It mainly occurs in the mineral cassiterite, and crystallizes with a tetragonal structure. It is a colorless, amphoteric and diamagnetic solid that is usually thought of as an oxygen-deficient n-type semiconductor.

It is insoluble in water, but dissolves in alkalis and acids. Tin dioxide is purified by reduction of the metal and burning tin in air.

Applications

Tin dioxide finds applications in the following areas:

Carbon monoxide detectors
Catalysis for the oxidation of aromatic compounds
Coatings and polishing powders
Ceramic glazes.

Chemical Properties

The chemical properties of tin dioxide are provided in the table below:

Chemical Properties
Chemical Formula	SnO₂
Molecular Weight	150.709
CAS No.	18282-10-5
Group	Tin – 14 Oxygen - 16
Crystal Structure	Tetragonal

Electrical Properties

The electrical properties of tin dioxide are provided in the table below:

Electrical Properties
Dielectric Constant	9.86
Band Gap	3.57 eV

Thermal, Mechanical and Optical Properties

The thermal, mechanical and optical properties of tin dioxide are provided in the tables below:

Thermal Properties
Heat of Formation	-280.7 kJ/mol
Standard Molar Entropy	57.2 J/mol K
Specific Heat Capacity	44.3 J/mol K

Mechanical Properties
Density	6.9 – 7 g/cm³
Melting Point	1630°C
Boiling Point	1800 - 1900°C

Optical Properties
Refractive Index	2.006

Safety Information

Safety Information
GHS Hazard Statements	H314 - Causes severe skin burns and eye damage H332 - Harmful if inhaled H335 - May cause respiratory irritation.
Safety Precautions	P350: Gently wash with soap and water P305+351+338: IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses if present and easy to do – continue rinsing.