Cheaper catalytic converter

Ni is a cheap catalyst

Catalytic converters change harmful substances in a car’s exhaust gasses, such as carbon monoxide, nitric oxide, nitrogen dioxide and hydrocarbons, into less harmful substances like carbon dioxide and water vapour by means of chemical reactions.

A three-way catalytic converter has three simultaneous functions: Reduction of nitrogen oxides into elemental nitrogen and oxygen: NOx→Nx+Ox. Oxidation of carbon monoxide to carbon dioxide: CO+O2→CO2. Oxidation of hydrocarbons into carbon dioxide and water: CxH4x+2xO2→xCO2+2xH2O.15 Aug 2020

All this magic is produced by the face centred cubic metal.  The most expensive and which is rhodium.

Price

RHODIUM USD/Oz 20000.00

So rhodium.  A platinum metal is massively expensive!  Titanium would work as well - but you still not cheap.

The cheapest easily accessible FCC metal is Nickle.

Conversion Nickel Price Price

1 Ton = 1,000 Kilograms Nickel Price Per 1 Kilogram 28.80 USD

Wow what price difference!  And they chemical actions will be just the same.  Catalysing the oxidation of the undesirable chemicals!, Conveting nitrous oxide, into nitrogen and oxygen.  Carbon monoxide into carbon dioxide - you get the idea!

The other, and metallurgical structure is the face centred cubic, which does not catalyse such reactions.

So Nickle is a very very cheap.  And will have the same chemical action as platinum metals!  Today 2022, the first of catalytic converters is a growing problem!  As the rhodium is so expensive.

But we can easily change over to a Nickle honeycomb.  And it may even be more effective!  As we can use more of the metal, and more surface area is a greater catalytic effect.  The Nickle is easily heat tolerant enough for our purposes.