People have been looking for more efficient ways to produce hydrogen for over 100 years, so when someone claims that they made a brake through that brakes the laws of physics it's common for it to be chalanged like was the case with Stan Meyers and in 1996, while it was still alive, he was found to be a fraud, but he also patented what he was doing, now patents are not proof that something works but are more so a copy right on an idea and a big part of patents is that they become part of public record and that they have to be clear enough that they can be reproduced by someone with an understanding in the area of the patented idea, in other words if you look up his patents you should be able to reproduce what he did, if of course you try to sell what you build then you are infringing on the patents, but you are free to build as many as you want for your self and your own use!
But the math says it doesn't work, reviews of what he did say it didn't work, laws of physics say it doesn't work and no one who has tried to reproduce what he did has been able to show proof that it does work.
Stanley Meyer's water fuel cell - Wikipedia, the free encyclopedia