Substitutes

Substitutes and Alternatives for Iridium

The availability of viable substitutes is a key factor in assessing Iridium's criticality. Across its 3 primary applications, substitution options range from commercially viable alternatives with performance trade-offs to applications where Iridium currently has no effective substitute.

Substitution Analysis by Application

The following table details available substitutes for Iridium across its primary applications, including the trade-offs involved:

Performance Trade-offs

In most applications, substituting Iridium involves measurable performance penalties. Iridium oxide is the only commercially proven anode catalyst for PEM electrolyzers; ruthenium can partially substitute but with lower stability; iridium loading reduction is a major research priority for green hydrogen economics. In high-performance applications such as spark plugs for aviation, these trade-offs can be particularly significant.

Research and Development

Active research programs are underway to develop improved substitutes and to reduce the amount of Iridium required per unit of product (thrifting). However, timelines for commercializing new alternatives typically span years to decades. The limited substitutability of Iridium is a primary driver of its high criticality rating, prompting government-funded substitution research programs.