Thorium nitrate is an inorganic compound with the chemical formula Th(NO₃)₄, which is an inorganic salt composed of thorium ions and nitrate ions. Thorium nitrate usually exists in the form of colorless or white crystals, which is highly oxidizing and can be stable in air, but can decompose at high temperatures to produce thorium oxide.

Thorium nitrate is a radioactive compound, and its main use is related to its radioactive properties as well as the special chemical properties of the thorium element. Here are some of the uses of thorium nitrate:

1. Nuclear industry: Thorium nitrate can be used as a potential fuel for nuclear reactors. While currently commercial nuclear reactors primarily use enriched uranium as fuel, the thorium-based fuel cycle is considered a potential alternative. Thorium-232 can be converted into the fissile isotope uranium-233 by neutron capture, which can be used in nuclear reactors.

2. Research and medicine: Thorium nitrate can be used as a radiotracer to play a role in scientific research as well as in medical imaging and treatment. For example, it can be used to track the flow of substances through the environment or to study metabolic processes within an organism.

3. Catalysts: Thorium nitrate or its derivatives can be used as catalysts in certain chemical reactions, such as in the petrochemical industry for the production of certain chemicals.

4. Electronic components: The high melting point and special electrochemical properties of thorium nitrate make it useful in the production of some electronic components, although this use may be less.

5. Radioactive source: Thorium nitrate can be used as a radioactive source in industrial, medical, and research fields, such as in radiometering, industrial flaw detection, and medical radiotherapy.