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UH Researchers Report New, More Efficient Catalyst for Water Splitting
- 24gttghh 9y agoAny idea what this catalyst actually is, perhaps a link to a paper, or even just an actual abstract?
- deleted 9y ago[deleted]
- Aaron1011 9y ago> The catalyst, composed of ferrous metaphosphate grown on a conductive nickel foam platform, is far more efficient than previous catalysts, as well as less expensive to produce.
- 24gttghh 9y agoMy skim-fu was weak. Thanks for pointing that out.
- pjreddie 9y agoI think this is the paper: http://pubs.rsc.org/en/content/articlepdf/2016/ta/c6ta02876d http://pubs.rsc.org/en/content/articlepdf/2016/ta/c6ta02876d Highly active and durable self-standing WS2/graphene hybrid catalysts for the hydrogen evolution reaction
- fudged71 9y agoFull Text: https://sci-hub.cc/10.1039/C6TA02876D https://sci-hub.cc/10.1039/C6TA02876D
- AdamTReineke 9y agoIs it this paper? https://scholar.google.com/citations?view_op=view_citation&hl=en&user=uVxFD-sAAAAJ&sortby=pubdate&citation_for_view=uVxFD-sAAAAJ:KqnX2w3egDsC https://scholar.google.com/citations?view_op=view_citation&h... Direct PDF link: https://www.researchgate.net/profile/Zhenhuan_Zhao/publication/315612407_A_TiO2FeMnP_CoreShell_Nanorod_Array_Photoanode_for_Efficient_Photoelectrochemical_Oxygen_Evolution/links/58da73c6a6fdccca1c53f8f3/A-TiO2-FeMnP-Core-Shell-Nanorod-Array-Photoanode-for-Efficient-Photoelectrochemical-Oxygen-Evolution.pdf https://www.researchgate.net/profile/Zhenhuan_Zhao/publicati... Abstract: A variety of catalysts have recently been developed for electrocatalytic oxygen evolution, but very few of them can be readily integrated with semiconducting light absorbers for photoelectrochemical or photocatalytic water splitting. Here, we demonstrate an efficient core/shell photoanode with a highly active oxygen evolution electrocatalyst shell (FeMnP) and semiconductor core (rutile TiO2) for photoelectrochemical oxygen evolution reaction. Metal−organic chemical vapor deposition from a singlesource precursor was used to ensure good contact between the FeMnP and the TiO2. The TiO2/FeMnP core/shell photoanode reaches the theoretical photocurrent density for rutile TiO2 of 1.8 mA cm−2 at 1.23 V vs reversible hydrogen electrode under simulated 100 mW cm−2 (1 sun) irradiation. The dramatic enhancement is a result of the synergistic effects of the high oxygen evolution reaction activity of FeMnP (delivering an overpotential of 300 mV with a Tafel slope of 65 mV dec−1 in 1 M KOH) and the conductive interlayer between the surface active sites and semiconductor core which boosts the interfacial charge transfer and photocarrier collection. The facile fabrication of the TiO2/FeMnP core/shell nanorod array photoanode offers a compelling strategy for preparing highly efficient photoelectrochemical solar energy conversion devices.
- pjreddie 9y agoI don't think so, Haiqing Zhou is not on that paper. Zhifeng Ren has a number of papers in this space.
- ksenzee 9y agoThe paper is at http://www.pnas.org/content/early/2017/05/10/1701562114 http://www.pnas.org/content/early/2017/05/10/1701562114: "Highly active catalyst derived from a 3D foam of Fe(PO3)2/Ni2P for extremely efficient water oxidation".
- kylehotchkiss 9y agoSome total n00b questions: Could this also be used in desalination? Turn into hydrogen, burn to convert back to water, feed it catalyst material like a fuel? (I'm not really sure how these catalysts work, do you like push water through them? and out comes gases?)
- astrodust 9y agoYou can do that already with electrolysis, but why would you? It's way more expensive than approaches like reverse osmosis.
- ars 9y agoIf you electrolyze salt water you will generate chlorine and hydrogen gas (instead of oxygen and hydrogen). The water will also contain lye from the leftover sodium.
- yomly 9y agoGCSE Chemistry :)
- kylehotchkiss 9y agoDOH (to me). This was the answer I needed to see. Thanks for saving me from this tangent!
- mmagin 9y agoSo, uh, do catalysts like this reduce the waste heat you get when electrolyzing water with a cruder setup? Because there's nothing but a specific minimum energy input that's going to break the bonds between hydrogen and oxygen.
- jkghsdjklsdgjkl 9y agoa catalyst by definition reduces the minimum energy input required for a chemical reaction to occur
- russdill 9y agoTo calculate the actual minimum energy, you also need to account for the H₂ bond and the O₂ bond.
- webkike 9y agoCould most uses of natural gas be replaced with hydrogen gas?
- maxerickson 9y agoWorst case you can convert the hydrogen to natural gas. There are a lot of processes that use methane for the hydrogen though.
- astrodust 9y agoAs soon as we can convert CO2 into hydrocarbons using solar or wind power in a way that's cost-competitive with conventional extraction we'll have turned an important corner in developing as a society.
- maxerickson 9y agoI wonder if that is more of a technological problem or more of a social problem (recognizing the costs of conventional extraction).
- astrodust 9y agoIf you can discover a way to cost-effectively synthesize hydrocarbons (CH chains) from CO2 and H2O, which contain all of the necessary components, you're pretty much guaranteed a Nobel prize. So far the process to do this involves a lot of messy intermediate steps, like hundreds of millions of years and enormous pressure in the mantle of the Earth.
- maxerickson 9y agoThere are pilot projects: http://www.audi.com/corporate/en/corporate-responsibility/we-live-responsibility/product/audi-e-gas-project.html http://www.audi.com/corporate/en/corporate-responsibility/we... (mentioned on https://en.wikipedia.org/wiki/Sabatier_reaction https://en.wikipedia.org/wiki/Sabatier_reaction) Who knows what the economics really are, but they don't sound dire.
- voicedYoda 9y agoI emailed Jeannie and she sent me the paper. I'm an idiot about finding a place to post it or host it (or find it), but the title of the paper is: "Highly active catalyst derived from a 3D foam of Fe(PO3)2/Ni2P for extremely efficient water oxidation" Searched for that and got this: http://www.pnas.org/content/early/2017/05/10/1701562114.abstract http://www.pnas.org/content/early/2017/05/10/1701562114.abst...
- JumpCrisscross 9y agoHow much more efficient is this than existing catalysts? Any obvious scaling impediments?
- drewbuschhorn 9y agoAs a former chemist in another but related field, this phrase is telling and part of why it is not in a higher impact journal: "We find that this catalyst, which may be associated with the in situ generated nickel–iron oxide/hydroxide and iron oxyhydroxide catalysts at the surface". This is generally code for "we're getting some sort of nano surface effect we're not 100% sure we understand or can replicate." I can't access the full paper, but the downfall of catalysts are usually: cost, durability, or unreproduciblity\creation cost. Getting nano surfaces to grow properly at industrial (10s of grams scale as one researcher said to me) is still more of an art than a science, with maybe one guy in a 10 person group able to get the substrate to perform. Not super aimed at this particular paper, but those are probably the reasons you don't see fireworks going off over inorganic labs around the country about this paper.
- gjem97 9y agoWhat are the key metrics for catalysts? Obviously cost is one. Round-trip energy efficiency? How does this measure up to existing commercial alternatives? How about against no-catalyst electrolysis?
- deleted 9y ago[deleted]
- marcosdumay 9y agoNot round trip efficiency. The reasonable metric is electrolysis-only efficiency. Longevity is another good one.
- giltleaf 9y agoHow much water would this process need to make enough energy for this to have an impact? Presuming we wouldn't use up our fresh water resources for this and that it would come from the ocean, but would this process create potential threats to the marine habitat as the mineral/chemical concentrations of the ocean water shifted?
- AnimalMuppet 9y agoWe wouldn't "use up" water at all for this. When you burn the hydrogen (to get the energy from it), it combines with oxygen and forms water. (Unless you're "burning" the hydrogen in a fusion reactor. But that takes much less hydrogen...)
- foota 9y agoCombustion of hydrogen produces water.
- mcphage 9y agoDON'T DROP IT IN THE OCEAN
- vmarsy 9y agomods, the original title should be preserved, currently it is : "U of Houston discovers catalyst that splits water into hydrogen and oxygen" But the original title is : "UH Researchers Report New, More Efficient Catalyst for Water Splitting" catalyst for water splitting aren't new. the article even says it : >The catalyst, composed of ferrous metaphosphate grown on a conductive nickel foam platform, is far more efficient than previous catalysts, as well as less expensive to produce.
- dang 9y agoYes. Thanks. Submitters: please don't rewrite titles unless they are misleading or linkbait. This is in the site rules: https://news.ycombinator.com/newsguidelines.html https://news.ycombinator.com/newsguidelines.html.
- weston 9y agoHi Dang, I submitted the article. I was trying to use the r/futurology article title which was, "University of Houston physicists have discovered a catalyst that can split water into hydrogen and oxygen, composed of easily available, low-cost materials and operating far more efficiently than previous catalysts, reported in the Proceedings of the Natural Academy of Sciences." HN has an 80 character limit for titles so I had to cut it down drastically from that.
- molyss 9y agoWhen I see anything related to splitting water into hydrogen, I'm worried that we're going to use water for energy on top of using to hydrate people. Still today, over 10% of the world population don't have access to clean water. I'm also curious on how clean the water needs to be to be used with this catalyst. AFAIK, most catalyst conversion need pretty pure water, in which case, we would not only use water, but use _clean_ water, which is even more scare than "dirty" water...
- maxerickson 9y agoThat aspect of it is a big meh. Reverse osmosis uses a great deal less energy than hydrolysis, so if you have so much energy that you are using a meaningful amount of water you also have so much energy that you can just make clean water.
- ThatGeoGuy 9y agoWouldn't that be a good thing in general though? If we use Hydrogen as our storage format, then you can do the following: Sea Water (H2O + sea junk) -> H2 Then later when generating electricity: 2 * (H2) + O2 -> H2O (fresh) + energy Naturally, the resultant H2O can be moved and recycled. I think a catalyst that splits water points towards a potential where we have more fresh water, not less.
- stale2002 9y agoHuman consumption of water is miniscule compared to other uses of water. If you are worried about water shortages, the place to fight that is water intensive farming, on luxury crops.
- deleted 9y ago[deleted]
- forgotpwagain 9y agoYou regenerate the water when H2 and O2 are recombined to produce electricity. Dan Nocera ( http://nocera.harvard.edu http://nocera.harvard.edu ) is very prominent in the water splitting field and has done a calculation in which a volume of an olympic sized pool would need to be split every second to replace all power sources on earth ( https://poptech.org/blog/daniel_nocera_on_personalized_energy https://poptech.org/blog/daniel_nocera_on_personalized_energ... ). It seems like a lot, but it would presumably be decentralized across many many locations. Additionally, you don't need 24 * 60 * 60 * olympic pool volumes -- you can cycle the same amount of water into/out of a fuel cell in a closed system.
- mabbo 9y ago> That would solve one of the primary hurdles remaining in using water to produce hydrogen, one of the most promising sources of clean energy. What? No. Hydrogen is not a source of energy, it's a storage format. A more efficient catalyst will certainly help with losses when storing the energy, but there's no net gain.
- pm90 9y agoYeah, this doesn't make sense. Also the problem isn't getting hydrogen, its to burn the hydrogen for energy efficiently and safely, which we currently have not found a way to do ... yet.
- maxerickson 9y agoYou can buy an H2 Toyota. https://ssl.toyota.com/mirai/fcv.html https://ssl.toyota.com/mirai/fcv.html There are also house scale fuel cells (that reform natural gas).
- marcosdumay 9y agoGot any reference on the efficiency and longevity of their fuel cells? Hydrogen fuel cells have a sweat spot at around 30% efficiency lasting for several years, and another at around 50% efficiency lasting for a few months. I have never seen anybody get a different set of numbers.
- maxerickson 9y agoNo idea. 30% is competitive with an internal combustion engine though. (and for a heated house you'd get better effective efficiency because the waste heat can be utilized)
- marcosdumay 9y agoThey are competing with batteries, not combustion engines. That's because the hydrogen must be generated somehow (and stored). If you go and generate the hydrogen from natural gas (so you have a natgas powered car, not much gain) you'll have to multiply those by a 40% to 50% conversion efficiency. If you generate it from water and electricity, your equivalent battery will have that 30% efficiency multiplied by another ~30% efficiency of electrolysis.
- knowaveragejoe 9y agoAnyone know what some "bigger picture" uses of this would be? It seems significant, but I'm not a chemist. Energy sources, desalination, etc?
- maxerickson 9y agoShort term it doesn't matter. Long term it makes it more viable to replace oil and other hydrocarbons used in industrial processes with energy, air and water.
- badosu 9y agoOne direct application would be more efficient ways to generate fuel for Hydrogen vehicles [0]. It would also be essential for mining fuel from asteroids or gas giant's moons as ice is not so rare, improving the sustainability of space operations. Hydrogen itself has a pretty big specific impulse, it's just not used more often than Kerosene for rockets due to safety issues. If you could achieve Metallic Hydrogen [1][2] then you would have the perfect fuel for navigating the solar system. [0]: https://en.wikipedia.org/wiki/Hydrogen_vehicle https://en.wikipedia.org/wiki/Hydrogen_vehicle [1]: https://en.wikipedia.org/wiki/Metallic_hydrogen https://en.wikipedia.org/wiki/Metallic_hydrogen [2]: http://iopscience.iop.org/article/10.1088/1742-6596/215/1/012194/meta http://iopscience.iop.org/article/10.1088/1742-6596/215/1/01...
- EvanAnderson 9y agoI am really miffed at this quote: "Hydrogen is the cleanest primary energy source we have on earth,” said Paul C. W. Chu, TLL Temple Chair of Science and founding director and chief scientist of the Texas Center for Superconductivity at UH. This seems like sensationalism and poor science communication to me. Hydrogen isn't a primary energy source.
- akiselev 9y agoPrimary in the sense that we can utilize hydrogen directly for energy (terrestrial fusion and fuel cell) just like with coal and other fossil fuels It has nothing to do with market share
- EvanAnderson 9y ago"Primary energy source" is a term with a specific meaning. I'm not talking about market share. Primary energy sources do not require any type of conversion. Fossil fuels, nuclear, wind, and solar are all primary energy sources. Free hydrogen isn't found in nature. It can be made by splitting water using energy from a primary source. The catalyst described in this press release makes that process more efficient, but it still takes energy from a primary source to create hydrogen. Reference: https://en.wikipedia.org/wiki/Primary_energy https://en.wikipedia.org/wiki/Primary_energy
- derefr 9y ago> Free hydrogen isn't found in nature. Sure it is; you just have to go kind of far out of the solar system before you'll start running into it. Molecular clouds of hydrogen are what makes those pretty Hubble pictures of nebulae. :)
- EvanAnderson 9y agoHeh heh... you're bringing back memories of "Fuel Scoops" in Elite on my C64!
- 9y ago
- subnaught 9y agoSome background and context from someone tangentially related to the field: 1. The overall idea here is to take an intermittent energy source (e.g. solar power) and "store" it as chemical fuel, in this case hydrogen and oxygen. This is what plants do, and we can also view fossil fuels as resulting from the "storage" of millions of years of solar energy. Note also that you get the water back when you burn the hydrogen, so there is no net consumption of water, it's just a carrier. 2. While you can split water without a catalyst, most of the energy gets wasted as heat, so this is not a great way to go if you're trying to do energy storage. 3. Efficient catalysts exist for this reaction, but they are based on rare and expensive metals, typically Pd, Pt, and Ir. As a result, there has been a search for catalysts involving "first-row" metals such as Fe, Co, Ni, etc. 4. There are variety of metrics for an electrocatalyst (efficiency, stability, cost, etc), but it's a fair bet that if this were significantly better than state-of-the-art, it would be in Science or Nature rather than PNAS.
- dnautics 9y agoBeyond the expensive of the metals another problem is duty cycles. Most transition metal catalysis is oxygen sensitive, and it seems like for some reason the first step of splitting water is creating oxygen. Plants go through great lengths to separate oxygen synthesis (photosystem II) from electron consumption. Most hydrogen production in lower organisms (like e coli) occurs entirely in anoxic conditions. Engineered systems for generating hydrogen via algae typically are temporally segregated (harvest light during day, produce hydrogen at night) which defeats the purpose and is also chemically steppy (carbohydrate intermediates).
- philipkglass 9y agoI am (was) a chemist but I find this research area somewhat puzzling. Electrolytic hydrogen production has been industrialized for more than a century. Put nickel electrodes in an aqueous solution of potassium hydroxide. Separate anode and cathode with a porous diaphragm. Run direct current through it. Get pure hydrogen. "Simple" alkaline electrolysis is only ~50% efficient, but that means there's only a factor of two efficiency gain possible no matter how good your catalyst. Large commercial electrolyzers from a decade ago reached ~70%. Why so much research on further marginal efficiency gains from new catalysts? Are there other costs that fall faster-than-linearly with improved efficiency?
- epistasis 9y ago>“Cost-wise, it is much lower and performance-wise, much better,” Having lower catalyst costs may allow for more installations that are used only intermittently. I know very little about the research in this particular field, but am not surprised that it's seeing more attention. As intermittent renewable electricity generation continues to get cheaper and replace fossil fuel sources, there's going to be a massive interest in using the large amounts of curtailed energy in someway. California is currently curtailing GWh per day of solar, and there's still a fairly low amount of renewable penetration. The question isn't necessarily about storing hours of energy, but perhaps weeks or maybe even months. Power to gas to electricity is currently only about 1/3 efficient, but depending on the cost curve of various battery technologies, there could be a big case for generating and storing a few months worth of methane mixed with hydrogen for winter months in the northern hemisphere. I bet there are likely to be far more research into combining electrolysis with methanation (perhaps with CO2 that's already dissolved in the water) or even chains of carbon. CNG automobiles, fueled with methane made from surplus renewable energy, might be a way for natural gas to be used in the future. We'll see if its ever economical, but there may be some great use cases for it.
- philipkglass 9y agoI agree that cheap-but-intermittent renewable electricity calls for differently optimized electrolyzer designs. Optimize for "cheap to manufacture and maintain" so you can afford to use them at a low duty cycle. If that is the underlying objective for this research, it's great, but doesn't come through clearly in the linked report. They mention efficiency in the headline, efficiency 7 times more in the body, and cost only twice, only in the body.
- ChuckMcM 9y agoWSU in 2016: https://news.wsu.edu/2016/10/25/better-water-splitting-catalyst/ https://news.wsu.edu/2016/10/25/better-water-splitting-catal... Missouri U: http://onlinelibrary.wiley.com/doi/10.1002/cssc.201601631/abstract;jsessionid=0CBBE4F0EBB05A15864081DE3851C125.f02t02 http://onlinelibrary.wiley.com/doi/10.1002/cssc.201601631/ab... Stanford: http://science.sciencemag.org/content/353/6303/1011.full http://science.sciencemag.org/content/353/6303/1011.full Lots and lots and lots of research going on in this space. So far nothing that can be used to produce hydrogen at scale.
- xupybd 9y ago>And unlike solar power, wind power and other “clean” energy, hydrogen can be easily stored Sure it's easier than other forms, but it's my understanding that there are some significant challenges in storing hydrogen?
- reacweb 9y agoNot that easy. There are always leaks. This causes safety concerns.
- jgamman 9y agohydrogen makes metals brittle and there can be catastrophic failure of valves, regulators etc. there are only 3 significant problems with hydrogen as an energy carrier to solve before it becomes ubiquitous: 1. how to make it 2. how to store it & transport it 3. how to use it IMO there was a time in the late 80s, early 90s when there was a chance it could be useful but the battery tech development over the last 25 years has nailed the coffin shut - hydrogen research persists because people with jobs know how to research hydrogen production.