Given the rarity and value of the PGM’s used in catalytic converters, has anything been done to find a cheaper solution?

Platinum group metals are some of the rarest minerals on earth, with high resistance to heat and properties of incredible strength that makes them key components for the making of catalytic converters.
Unfortunately, nothing has been done to find a cheaper solution, which makes the recovery of PGM’s even more important.

Lombong platinum