Trioctylphosphine oxide (TOPO) is an organophosphorus compound with the formula OP(C8H17)3. Frequently referred to as TOPO, this compound is used as an extraction or stabilizing agent. It is an air-stable white solid at room temperature.

Tri-n-octylphosphine oxide is a solvent used in the extraction of metals, especially uranium, zirconium and hafnium. It is also used as an auxiliary reagent in the solvent extraction of metals. It is also used to extract hydrogen bonding organic compounds.

It has also been used in the laboratory in the synthesis of nanoparticles. It can function both as a solvent for the reaction mixture and as a coordinating agent to stabilize the surface of the particles. It can also coordinate with metal ions, change the form of metal precursor and affect the formation kinetics of nanoparticles during the synthesis.

Oleylamine is an organic compound with a molecular formula C₁₈H₃₅NH₂. It is an unsaturated fatty amine related to the fatty acid oleic acid. The pure compound is a clear and colorless liquid.

TRI N OCTYLPHOSPHINE OXIDE AR