Claims being made in the article are misleading and the research itself - which is actively being pushed on mutliple social media channels in a way that borders on the absurd - is massively overstated.

>“We have split natural seawater into oxygen and hydrogen with nearly 100 per cent efficiency

No, that's a BS claim. The process is not "nearly 100%" efficient. What they have actually done is that they achieved nearly the same efficiency as with conventional electrolysis using standard catalysts and pure water.

As per the abstract from the actual paper: >[...]and similar performance to a typical PEM electrolyser operating in high-purity water.

This whole thing - i.e. "we need to solve seawater electrolysis to make the hydrogen economy happen" is absolute BS, for the simple reason that the problem doesn't actually exist, because conventional electrolysis coupled with reverse osmosis (SWRO) is basically as efficient as it gets:

>Our analysis reveals there are limited economic and environmental incentives of pursuing R&D on today's nascent direct seawater electrolysis technology. As commercial water electrolysis requires a significant amount of energy compared to SWRO, the capital and operating costs of SWRO are found to be negligible. This leads to an insignificant increase in levelized cost of H2 (<0.1 $ per kg H2) and CO2 emissions (<0.1%) from a SWRO-PEM coupled process.

>https://pubs.rsc.org/en/content/articlelanding/2021/ee/d1ee00870f

"Direct electrolysis" results in insignificant gains. Purifying seawater is not what makes the process inefficient and not having to purify the water doesn't make it markedly more efficient let alone cost saving.

What's "preventing the hydrogen economy from happening" is not that we have to deal with seawater - it's that electrolysis itself takes massive amounts of energy and isn't efficient. You don't improve the underlying economic obstacles by slashing less then 10 cents from the price of a kg of hydrogen.

The "obstalce" is not seawater, it's the inefficiency of electrolysis. And the people pushing this research just told you that somebody has come with a way that's less efficient than regular electrolysis.