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Comment by partacus | Hacker News Reader

How is this a story? Did someone at Stanford open up a grade 10 Chemistry textbook?

From the article: "Using nickel and iron, which are cheap materials, we were able to make the electrocatalysts active enough to split water at room temperature with a single 1.5-volt battery. This is the first time anyone has used non-precious metal catalysts to split water at a voltage that low. It's quite remarkable, because normally you need expensive metals, like platinum or iridium, to achieve that voltage."

But it really isn't. The only thing of minor note here is room temperature vs doing it at 60 deg C.

At scale, that's a good bit of energy, I would assume. But I had the same reaction as you did. "My 7th grade science class did that..."

They're overselling the science. This is certainly not the first time anyone has used non-precious metals to split water at low voltages. Both Ni oxide and Ni-Fe oxide systems that they use in their paper are well known in the literature. Ni oxides have been published back in the 1950s while Ni-Fe oxide catalysts were introduced in the 1980s. However, they do claim that their NiO/Ni/CNT system is novel, which may be true.

In their experimental setup, they target 20 mA/cm2 current density. To achieve that, they can just increase the amount of catalyst they use. The geometric area (cm2) will remain the same, but the surface area will increase which will correspondingly raise current density. For example, one can stack sheets of carbon aerogel to achieve the same current density.

"But scientists have yet to develop an affordable, active water splitter with catalysts capable of working at industrial scales." "The nickel/nickel-oxide catalyst significantly lowers the voltage required to split water, which could eventually save hydrogen producers billions of dollars in electricity cost"

Making it more plausible I suppose. The only thing I have a problem with is that they used a battery, which required electricity to be initially charged. The electricity had to be generated somehow. If we plan to use <insert renewable energy here> to charge the batteries to split the water to generate the hydrogen to power our cars, I think very few people will be driving.

You wouldn't actually use a battery. It just makes a neat demo.

Article seems to be a bit dumbed down. Many people are familiar with the school experiment where you do electrolysis using a battery (A water splitter from an ordinary AAA battery!!!)

Article links to the paper. Unfortunately only the abstract is free. Seems like the advance is making it more efficient. Electrolysis at a usable level with just AAA-level voltage.

Agreed! I remember doing something similar for my science fair. Unless these scientist at Stanford have devised a way to dramatically improve the efficiency of the process then this is not a discovery at all!

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