Iridium and ruthenium are used together in several industrial chemical processes, including the manufacture of acetic acid, a key intermediate in the manufacture of other bulk chemicals.
Both metals are used together in electrode coatings able to withstand the very harsh operating environment of a wide range of electrochemical processes, including the production of bulk chemical intermediates chlorine and sodium hydroxide.
In the electrical sector, iridium’s high temperature stability and purity have led to the use of iridium crucibles in growing materials for light emitting diodes (LED) for energy efficient lighting and, more recently, materials for surface acoustic wave (SAW) filters, devices found in increasing quantity in all smartphones and numerous other devices. Some overcapacity has seen crucibles originally set for the LED industry repurposed for the SAW filter industry.
Iridium tips improve the performance of automotive spark plugs to improve the efficiency of the combustion process in gasoline engines, again relying on high temperature stability, and linking to the opportunities and threats experienced by the other PGMs in the automotive market.
Along with platinum, iridium is also used as a minor alloying component in some medical devices, notably guide wires and stents, by virtue of its biocompatibility and mechanical properties for micromachining complex tiny devices.
Iridium is beginning to play an important role in the developing hydrogen economy, as part of the catalyst package in combination with platinum in proton-exchange membrane (PEM) electrolysers for the production of hydrogen.
Information above provided by SFA (Oxford)