I am always suspicious of claims that something as high-tech as this is 'carbon neutral'. At a minimum, to be carbon neutral this hydrogen would have to be produced from ethanol which had no fossil-fuel inputs. That means non-mechanized, no-fertilizer farming for the grain the ethanol was made from, no trucking of the grain or ethanol, and only biomass to be used as fuel for the distillation.

It sounds unlikely.

Let's not even consider where the rhodium, palladium and cerium came from and how they were processed and fabricated into nanoparticles.