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Scientists at Stanford develop water splitter that runs on ordinary AAA battery

news.stanford.edu

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Re: Scientists at Stanford develop water splitter that runs on ordinary AAA battery

#11

Post by Crito »

lutorm wrote: post #6

... and not a single word about how the necessary electricity needed to make this "zero emission fuel" is supposed to be produced. Plus, all I know about hydrogen points to it not being anything close to "an ideal fuel for powering vehicles, buildings and storing renewable energy". It has very low density, requires cryogenic storage or very heavy pressure vessels, migrates through materials, and is explosive when mix…

Even when cryogenic (and hydrogen needs to be deeply cryogenic to remain liquid. 20K compared to liquid nitrogen's 77K) it is not particularly dense. It barely makes sense to use it in rockets since it has such poor density, causes embrittlement, and requires a great deal of insulation if you want to store it for any reasonable amount of time.

If it is a chore to use the stuff for rocket science, I don't see it becoming a reasonable power source in more casual applications.

If I am factually incorrect about anything here, I honestly do want to be told so.

Re: Scientists at Stanford develop water splitter that runs on ordinary AAA battery

#12

Post by nardi »

I'm amazed at the ignorance in these comments.

First, yes this is cool new science. No one imagined nickel would work as a water-splitting electrocatalyst. This is very surprising, and awesome.

Second, the point of water-splitting is obviously not power generation. It's power storage, just like a battery, but with better transport and storage characteristics.

Re: Scientists at Stanford develop water splitter that runs on ordinary AAA battery

#13

Post by jostmey »

partacus wrote: post #2

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

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!

Re: Scientists at Stanford develop water splitter that runs on ordinary AAA battery

#14

Post by kstenerud »

sirdogealot wrote: post #9

This isn't news. "The researchers also plan to develop a water splitter than runs on electricity produced by solar energy." Unfortunately that approach would be less efficient that simply transferring the electrical energy to an electric motor. Light > Electricity > Hydrogen > Electricity > Electric Motor is longer than Light > Electricity > Electric Motor

For a motor vehicle, you need Energy > Storage > Motor, so Light > Electricity > Electric Motor won't work in this case.

Re: Scientists at Stanford develop water splitter that runs on ordinary AAA battery

#15

Post by nardi »

lutorm wrote: post #6

... and not a single word about how the necessary electricity needed to make this "zero emission fuel" is supposed to be produced. Plus, all I know about hydrogen points to it not being anything close to "an ideal fuel for powering vehicles, buildings and storing renewable energy". It has very low density, requires cryogenic storage or very heavy pressure vessels, migrates through materials, and is explosive when mix…

This is like commenting on a battery tech article with, "Yes, but how are we going to charge all of those batteries?!" Or power grid technology, "Great, but where is the electricity going to come from?!?!"

Re: Scientists at Stanford develop water splitter that runs on ordinary AAA battery

#17

Post by aidenn0 »

nardi wrote: post #15
lutorm wrote: post #6

... and not a single word about how the necessary electricity needed to make this "zero emission fuel" is supposed to be produced. Plus, all I know about hydrogen points to it not being anything close to "an ideal fuel for powering vehicles, buildings and storing renewable energy". It has very low density, requires cryogenic storage or very heavy pressure vessels, migrates through materials, and is explosive when mix…

This is like commenting on a battery tech article with, "Yes, but how are we going to charge all of those batteries?!" Or power grid technology, "Great, but where is the electricity going to come from ?!?!"

There is no mention of efficiency either; the efficiency of hydrolysis is often around 50% which means that almost anywhere you live it would be better from a CO2 standpoint to just put gas in your car.

Re: Scientists at Stanford develop water splitter that runs on ordinary AAA battery

#18

Post by alex_duf »

nardi wrote: post #12

I'm amazed at the ignorance in these comments. First, yes this is cool new science. No one imagined nickel would work as a water-splitting electrocatalyst. This is very surprising, and awesome. Second, the point of water-splitting is obviously not power generation . It's power storage , just like a battery, but with better transport and storage characteristics.

right, but using a AAA battery which is already storing energy doesn't serve any purpose.

But I agree with you, efficient-cheap catalyst is needed indeed. I'd like to know the efficiency of the system though...

Re: Scientists at Stanford develop water splitter that runs on ordinary AAA battery

#20

Post by mikexstudios »

nardi wrote: post #12

I'm amazed at the ignorance in these comments. First, yes this is cool new science. No one imagined nickel would work as a water-splitting electrocatalyst. This is very surprising, and awesome. Second, the point of water-splitting is obviously not power generation . It's power storage , just like a battery, but with better transport and storage characteristics.

"No one imagined nickel would work as a water-splitting electrocatalyst."

Not true. It has been known since the 1950s (and likely earlier) that Ni oxides can function as water splitting catalysts (both for hydrogen evolution and oxygen evolution half reactions).

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