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>150 ± 20 nmol s−1 cm−2

Isn't this miniscule? Is this commercially viable?

Edit: The molecular mass of nitrogen is 28, so 1 mol is 28 grams, so 150 nmol is 28 x150 nano grams = 4.2 micro grams. How much gas is this?

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Incorrect in multiple respects. The molar mass of N is 14.006747 g/mol, while ammonia is 17.03052 g/mol. Gas expands to fill the container, so it's only worth discussing in mass terms.

It's rate of production over the area of the catalyst. Put another way, that's 1.5 ± 0.2 mmol/m²s or 25.5 ± 3.4 mg/m²s.

24 hours of production over a catalyst with an area of 1000 m² would create 25 ± 3.4 t. That's about the product weight of a typical full cold / cool towed trailer tank sent to large-scale customers. A commercial ammonia refinery would need many multiples of this area to be economically viable.

https://alliancetruckandtank.com/products/transport-trailers...

Any idea how tightly can these cells likely be packed in 3d? Is 1000 m² likely to be 1 m³ or 1000 m³?

For hydrogen electrolysis they typically quote around 1 A/cm^2 current. One Coulomb is ~6e18 charges, whereas one mole is 6e23 molecules, so that makes about 1e-5 H atoms per cm per second. Of course making one molecule of ammonia needs 4 H atoms, so it works out to something like 16x lower productivity. I assume it's not competitive as is.

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