[westurner]

teal hydrogen: electrolytic catalysis, renewable feedstocks

turquoise hydrogen: high-temp pyrolysis of methane

So e.g. [1] is turquoise hydrogen.

[1] "Production of hydrogen and carbon nanotubes from methane using a multi-pass floating catalyst chemical vapour deposition reactor with process gas recycling" (2025) https://www.nature.com/articles/s41560-025-01925-3

A renewable feedstock process that yields Hydrogen and O-CNT would be yielding teal hydrogen.

A natural gas process that yields Hydrogen and O-CNT would be yielding turquoise hydrogen.