Rhodium is a chemical element represented by the chemical symbol Rh and the atomic number 45. It is a hard silvery-white metal and is classified as a transition metal from the platinum group. It is a rare element that is only found in platinum ore or nickel ore, from which it is obtained commercially. It is extremely resistant to corrosion and this characteristic makes it viable for a number of different applications.
Uses of rhodium
The largest use of rhodium, about 80% of the world’s production, is as a catalyst in three-way catalytic converters. A catalytic converter is a device fitted to vehicle to convert toxic exhaust emissions into safer substances.
Rhodium is also used in the jewelry industry where it is often electroplated onto platinum or white gold to produce a reflective white surface in a process called rhodium flashing. It is also used as a coating for sterling silver to reduce the chance of tarnishing. Plated rhodium is sometimes used for optical instruments.
It is also used in some alloys containing platinum and palladium for hardening and to provide increased corrosion resistance.
A specialist device called a rhodium neutron detector is used to measure the neutron flux level in nuclear reactors.
It can also be used as an electrical contact material.
Did you know?
A rhodium-plated disc was given to singer-songwriter Paul McCartney by the Guinness Book of World Records to commemorate his achievement of becoming the all-time best-selling songwriter and recording artist.