Yes, but if you read just a little further in that article: “The combustion of ammonia in air is very difficult in the absence of a catalyst” Practically speak

Yes, but if you read just a little further in that article: “The combustion of ammonia in air is very difficult in the absence of a catalyst” Practically speaking, NOx formation is difficult to avoid in combustion applications and would require safeguards/mitigations just as it is in Diesel engines. Another issue is that the whole concept of green ammonia relies on having sufficient green hydrogen feedstock to produce it with in the first place. I do recommend reading the Royal Society policy paper linked in the parent post!