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Power Science

New Catalyst Is Better At Splitting Water Into Hydrogen And Oxygen (phys.org) 133

schwit1 shared an article from Phys.org: Splitting water into hydrogen and oxygen to produce clean energy can be simplified with a single catalyst developed by scientists at Rice University and the University of Houston. The electrolytic film produced at Rice and tested at Houston is a three-layer structure of nickel, graphene and a compound of iron, manganese and phosphorus. The foamy nickel gives the film a large surface, the conductive graphene protects the nickel from degrading and the metal phosphide carries out the reaction... Rice chemist Kenton Whitmire and Houston electrical and computer engineer Jiming Bao and their labs developed the film to overcome barriers that usually make a catalyst good for producing either oxygen or hydrogen, but not both simultaneously... Whitmire said the material is scalable and should find use in industries that produce hydrogen and oxygen or by solar- and wind-powered facilities that can use electrocatalysis to store off-peak energy.
In a comment on the original submission, Slashdot reader Martin S. opines, "If we can crack H20 and C02 we could make fuel to run existing vehicles with existing infrastructure and that fuel could be carbon neutral by using off peak renewable energy from wind farms and solar."
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New Catalyst Is Better At Splitting Water Into Hydrogen And Oxygen

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  • For passenger vehicles. And they always will be

  • After all, we'll always have enough water [wikipedia.org], right?

  • Which is that?

    Do current combustion motors run on hydrogen? Not really.

    Are current cars able to contain hydrogen? Not really.

    Are current tankers able to transport hydrogen gas? Not really, they're made for a liquid.

    Are current gas stations able to dispense hydrogen? Nope, a station's storage, machinery and dispenser nozzle sure as hell aren't made for a gas.

    So I'm not seeing much reuse potential here. Now the end-game would look kinda similar to a gasoline infrastructure on the surface, except for the part

    • by fahrbot-bot ( 874524 ) on Sunday August 06, 2017 @06:37PM (#54952815)

      I think the implication is that with abundant, easily generated H + O + C one could make hydrocarbon fuels, like gasoline.

      • by drinkypoo ( 153816 ) <martin.espinoza@gmail.com> on Sunday August 06, 2017 @06:44PM (#54952869) Homepage Journal

        I think the implication is that with abundant, easily generated H + O + C one could make hydrocarbon fuels, like gasoline.

        There are pilot hydrogen fuel stations with on-site electrolysis, the idea being that you use off-peak power to fill the tanks, and don't have to transport hydrogen. Then you feed this into a FCEV. There is hydrogen fueling infrastructure in California, and more will be coming whether it makes sense or not.

        • The problem with this idea is that simply charging a battery is about twice as efficient. And it can already mostly take place in numerous garages. There's still significant extra expenses for the hydrogen route.
          • The problem with this idea is that simply charging a battery is about twice as efficient. And it can already mostly take place in numerous garages.

            After the fuel cell, the hydrogen storage tank is the most expensive component of a HFCV. It's not realistic to put those in people's houses. Even if you only produce H2 when the vehicle is connected (at night, presumably) the compressor system needed to store the H2 is very expensive. Even the compressor for CNG costs substantially more than a charging station.

            The ideal low-emissions (water vapor is an emission, however benign) combination IMO is a plug-in hybrid with a hydrogen fuel cell as a range extend

    • This 'fuel' is a relatively stable metal powder.
    • Or the hydrogen could be used to generate electricity for the grid to charge electric cars to which we are moving to. So if someone wants to charge their car at night the electricity that was generated during the day could have been converted to H2 gas, stored until needed, and then a plant somewhere on the grid could use the H2 gas to produce electricity and send it onto the grid.

      No need to haul H2 gas everywhere or for cars to carry it. A plant would take the excess electricity off the grid to convert wat

      • As long as creating H2 gas is less efficient then charging a Li battery, this will never happen. Batteries are more efficient and less dangerous. When used vehicle batteries start showing up in a few years time - availability will no longer be a problem.
        • I was just pointing out that there was no need to carry H2 gas around on every car and changing the whole infrastructure wasn't required like the person I was originally responding to assumed. Just like I wouldn't assume that a Li battery is the most efficient or cost effective storage in a large scale grid storage system. I haven't looked it up. Elon Musk has proposed using Li batteries but then he would as he is in the business of selling Li batteries.

    • Do this and you create methane, which you can further react into larger hydrocarbons to create synthetic gasoline.

      But I doubt this will happen. The technology for electric vehicles is moving apace, will soon become less expensive than the high-level engineering required to produce an internal combustion drivetrain, and it is much more convenient and cheaper to run. The writing is on the wall for the internal combustion engine.

      • by ceoyoyo ( 59147 )

        We'll use synthetic fuel in airplanes. It's going to require some major technological breakthroughs before battery powered airliners are practical.

        Hydrogen and synthetic hydrocarbons are also handy in rockets, as a storage medium for solar and wind power, and as a convenient method of moving electricity long distances.

    • by jezwel ( 2451108 ) on Sunday August 06, 2017 @10:42PM (#54953843)
      You could potentially convert the hydrogen, oxygen, plus atmospheric carbon (CO, CO2) into a synthetic fuel using one of the already in use processes:
      https://en.wikipedia.org/wiki/... [wikipedia.org]

      The rest of the storage, distribution and usage infrastructure is already in place, so the challenge is creating an efficient factory that takes in air + water, splits it up, and cranks out gas as an output.

      • The rest of the storage, distribution and usage infrastructure is already in place, so the challenge is creating an efficient factory that takes in air + water, splits it up, and cranks out gas as an output.

        And quite the challenge it is. I saw no mention of the water used, so I am assuming it is fresh. So either saline water will have to be desalinated before use, creating disposal issues or local hypersalinization ocean conditions, or fresh water will be used, creating yet another pressure upon the ecosystem. This means the source will be erratic. We are to the point in the northeast where trees are falling over because the soil is saturated, but that isn't always the case. But even we have had droughts, and

        • "And quite the challenge it is."

          It needs to be nuclear-thermal and noone's willing to invest in that kind of tech (yet)

    • by Kazymyr ( 190114 )

      The most efficient way to store hydrogen in a way that would make refueling a car currently is not as liquid hydrogen, but as metal hydrides. One of the most efficient, and which has been used for quite some time (though we don't really think of it as a hydrogen-storing device) is an alloy of nickel and lanthanum - the devices using it are NiMH batteries.
      The way efficient refueling of a hydrogen car would work is: the fuel tank is removable, and contains NiMH. Once it is spent, it can be taken off at a fuel

    • by Whuffo ( 1043790 )
      It's worse than that. The energy released by burning hydrogen is less than the energy used to electrolyte it. Rather than take a loss in the conversion, just use that electricity to run an electric car. No need for fancy electrolysis cells ans high pressure hydrogen storage.
      • by Bengie ( 1121981 )
        Unless you plan on having a cable attached to the car, you still need to charge a battery, which will result in a loss of energy. Assuming both have similar holistic inefficiencies, what are the pro/cons for each approach?
    • by MobyDisk ( 75490 )

      It might also be helpful in making jet fuel from electricity [slashdot.org], which the US Navy would like to do to make aircraft carriers more sustainable.

  • Rice chemist Kenton Whitmire and Houston electrical and computer engineer Jiming Bao and their labs developed the film to overcome barriers that usually make a catalyst good for producing either oxygen or hydrogen, but not both simultaneously. "Regular metals sometimes oxidize during catalysis," Whitmire said. "Normally, a hydrogen evolution reaction is done in acid and an oxygen evolution reaction is done in base. We have one material that is stable whether it's in an acidic or basic solution."

    So, they have a catalyzer which is good for both oxygen and hydrogen production, but not both simultaneous at the same time?

    • Haven't read the article, but I presume one atom/molecule is released, and the other is bound to the catalyst or the media in which the reaction takes place.

    • One catalyst to rule them all ... and in the darkness, bind them.

    • by Rutulian ( 171771 ) on Monday August 07, 2017 @07:54AM (#54955281)

      Basically, there is no such thing as a "perfect" catalyst. All catalysts eventually undergo some sort of degradation process as a side reaction and fail. So the trick is usually not finding a catalyst that can promote a particular chemical reaction (the reaction mechanisms for most of these things have been known for decades), but a combination of catalyst+stabilizer+reaction conditions that provide decent yields at reasonable costs.

      In this particular case, electrolysis of water takes place as two half reactions: a hydrogen evolution reaction (HER) and an oxygen evolution reaction (OER). While the reactions must take place simultaneously, they are nonetheless fundamentally different reactions that take place at the cathode and anode, respectively. The HER is relatively facile, but the OER is much more thermodynamically unfavorable. Different catalysts are used at the cathode and anode to promote these two half reactions, but the problem usually resides with the OER. To get good OER catalysis using cost-effective materials, you usually need to perform the reaction under alkaline conditions. But under alkaline conditions the HER takes a major hit, both uncatalyzed and using common catalysts, such as platinum. A nice review here,
      http://onlinelibrary.wiley.com... [wiley.com]

      So there you go, that's the basic problem that this group is trying to solve. Haven't looked at the article carefully, but looks promising.

  • so you just fill your tank with water, turn on an electric water pump and this H20 cracker gadet and soon you have both hydrogen and oxygen to feed an internal combustion engine and the exhaust is just hot humid air with a little steam and some water droplets dripping out of your tail pipe = clean engery
  • Night? Any time solar is available is, like, time to use power? I for one don't sleep that much when the sun is up...

    • Morning. Peak electricity use typically doesn't start until closer to noon.

      And that's assuming photovoltaic solar. Solar thermal has other options.

    • Night? Any time solar is available is, like, time to use power? I for one don't sleep that much when the sun is up...

      Off-peak solar means solar produced in excess of peak demand.

  • Making Hydrogen isn't hard at all. The problem is safely bottling it up, transporting it to a useful location, filling a vehicle tank with it, making that tank safe for standard DOT highway compliant vehicles, and then converting the stored chemical power into electricity without needing a half kilo of platinum per vehicle.
    • There are three big problems with electrolysis of water for hydrogen. One, catalyst durability. Two, availability of sufficiently clean feed stock. Three, low efficiency of the process, both overall (see point two) and at the actual point of electrolysis.

      These researchers claim to have solved problem one and addressed problem three, though I did skim the article and I don't recall seeing any specific percentage improvements mentioned... nope, I read it again, there's nothing like that in there. I'll wait fo

  • Plug Power rec'd backing for several hundred millions from Amazon and Walmart for fuel cells for warehouse forklifts. More specialized use cases like a forklift may offer better potential near term since vehicles operate around a central location. Later the storage , transport costs which appear high for suburban homes may not need for personal use. Instead focus on fleet vehicles where economies of scale more practical. Modest technological advances like catalysts will help but a ways off for wide spread
    • Warehouse fork lifts are ideal cases for batteries, because you're in an environment where battery swaps are realistic and because you don't want flammable gases inside of warehouses if you can avoid it. Also, all that heat and water vapor has to go somewhere. Maybe if that warehouse were a greenhouse...

  • Yet another stupid idea that places cars in direct competition with the human food chain. Remember what happened when Ethanol was advocated for saving the environment? Food prices sky rocketed as cars began consuming the same food as humans. Poor people starved to death in the thousands. On top of it, Ethanol was a highly inefficiency gas doomed to failure.

    So yeah, please don't develop technologies that have cars consuming anything that human beings rely on. It won't be a pretty sight.

    • Food prices sky rocketed as cars began consuming the same food as humans.
      On which planet?
      Poor people starved to death in the thousands.
      On which planet?

      • by Anonymous Coward

        Earth. Just because you don't want to believe something doesn't mean it's not true.

        http://www.globalwarming.org/2013/01/09/ethanol-mandates-cause-hunger-and-child-malnutrition-in-guatemala/

    • Remember what happened when Ethanol was advocated for saving the environment? Food prices sky rocketed as cars began consuming the same food as humans.

      That's not how distilled water works. It takes energy as input no matter what purpose you put it to. If we don't have fuel then we don't go and then we don't have food, either. So if you're making fuel with water instead of putting it into humans, well, it's still part of being able to put food into humans.

      It is daft to use farmland to produce fuel, but we could be building algae raceway ponds in the desert and stirring them with solar paddlewheels, then making the algae into biofuel; centrifuge out the lip

    • Food prices sky rocketed

      I seriously, don't think you understand the sheer amount of corn that is grown in the US. [usda.gov] To think that the small amount of ethanol that we produce actually affects the price of corn (and everything that relies on it) is seriously laughable. Business people are always looking for scapegoats to jack up the prices dude. That's like US economics 101. War in Iraq? Hell, raise the price of gasoline. Flood in Japan? Raise the price of Kraft cheese singles. Brexit? Might as well add $3 for everything made

  • It still (and always will) takes more energy to split water into H2 and O2 than is released putting it back together. It is an efficient way to store energy, but it doesn't make energy, it uses it. This is a battery, not a power source.
  • If we can crack H20 and C02 we could make fuel

    And if we could find us a Maxwell's Demon [wikipedia.org] or two, we wouldn't even need to do that...

  • Enough with these nay-sayers already! They don't seem to have even basic reading comprehension skills and even less knowledge of the materials sciences that goes into developing new catalysts.

    Finding a way to close the fuel cycle for fuel cells is the key to creating a usable power source for transportation and for storing energy while also controlling the "carbon dioxide (CO2) cycle" that releases too much excessive carbon dioxide into the atmosphere.

    And the Trump comments are just morons being moronic.

  • I've never been a fan of cracking water to separate the H and O and then burning it. Sure, it's clean, but the cool thing about water is it doesn't go away. Wanna really see the environment get f---ed, start permanently removing water from Earth so we can have clean smelling tail pipes but the whole planet turns into a desert. Now, if we can find ways to add water to the planet from outside such as mining asteroids and comets, great. Break that stuff down and burn!

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