UNSW scientists say they have key to unlock low-cost green hydrogen

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Australian scientists say a new green hydrogen production technique could slash costs by avoiding the need for expensive metals.

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Research from Australian scientists appears to have unlocked new techniques for the production of renewable hydrogen from electrolysis, that they believe could lead to significantly reduced costs.

In a paper published in the journal Nature Communications, researchers from UNSW, Griffith University and the Swinburne University of Technology have invented a new method of coating electrodes used in the electrolysis process to produce hydrogen.

Using electrolysis, hydrogen can be extracted by water using electricity, with the electricity working to split the hydrogen atoms in water from the oxygen atoms to which are bonded.

Electricity is passed through water using electrodes which have been traditionally consisted of precious metals like platinum and iridium, which allow for high energy efficiencies in the electrolysis process but are hugely expensive.

The research led by scientists at the UNSW found that it was possible to achieve improvements in energy efficiency while using common, low-cost, metals like iron and nickel as the electrolysis catalysts. These materials are thousands of times cheaper than materials like platinum, and their use could contribute to driving down the costs of hydrogen production.

The research team has invented a process to coat the electrodes with a nano-material, which establishes an interface at the nano-scale between the electrodes and the water, which facilitates the splitting of water into hydrogen and oxygen while requiring significantly less energy.

“What we do is we coat the electrodes with our catalyst to reduce energy consumption,” UNSW’s professor Chuan Zhao said.

“On this catalyst there is a tiny nano-scale interface where the iron and nickel meet at the atomic level, which becomes an active site for splitting water. This is where hydrogen can be split from oxygen and captured as fuel, and the oxygen can be released as an environmentally friendly waste.

“The nanoscale interface fundamentally changes the property of these materials,” Zhao added. “Our results show the nickel-iron catalyst can be as active as the platinum one for hydrogen generation.

“An additional benefit is that our nickel-iron electrode can catalyse both the hydrogen and oxygen generation, so not only could we slash the production costs by using Earth-abundant elements, but also the costs of manufacturing one catalyst instead of two.”

When the electrolysis process is powered using renewable electricity, it offers a source of zero-emissions hydrogen that can then be used as a transport fuel, stored as a backup supply of energy or as a source of thermal heat used in industrial processes.

“At the moment in our fossil fuel economy, we have this huge incentive to move to a hydrogen economy so that we can be using hydrogen as a clean energy carrier which is abundant on Earth,” professor Zhao said.

“We’ve been talking about the hydrogen economy for ages, but this time it looks as though it’s really coming.”

Last month, Australia’s chief scientist Dr Alan Finkel delivered the National Hydrogen Strategy to the COAG Energy Council, that both Finkel and the energy ministers hope will provide a pathway to Australia seizing the multi-billion dollar potential that a hydrogen production industry could provided to Australia.

“We’re hoping our research can be used by stations like these to make their own hydrogen using sustainable sources such as water, solar and these low cost, yet efficient, catalysts,” Zhao added.

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8 Comments
  1. GlennM 1 week ago

    and what is the efficiency of the splitting process ??

  2. riley222 1 week ago

    83.7%, according to the abstract of the published paper.

  3. Arnold Garnsey 1 week ago

    83%conversion can be thought of as a conversion loss of 17% which would be comparable to ‘basket’ of battery losses.
    There are several other conversions before the round trip is completed depending on the intended end use but getting the cost and life from earth abundant materials is critical.
    I wouldn’t pretend to follow the physics of catalysis but understand that the nano (quantum effect) technology’s library is nascent which suggests prospects for greater efficiencies are high.
    A lot of concern about the life expectancy from the (noble metal) catalysts with variable or intermittent energy source as from R.E. oversupply.

    • Ren Stimpy 1 week ago

      A nascent library might suggest but doesn’t necessarily translate into any prospects.

      Right now, well proven far beyond the ‘prospect’ stage is the lithium ion battery. That is something solid that storage production investment can hang their hat on. There are three large markets for it ffs.

  4. Honest Mike 1 week ago

    high efficiency electrolysers have been around for more than a decade so not sure what is new here. I approached members of the qld government about 8years ago and at the time they were so excited about the electrolysers that Energex/Ergon were talking about procuring their own electrolysers and therefore creating their own green hydrogen business/department/division, which isnt exactly in line with their core business or supporting the commercialization of innovation in private enterprise…. in short, the technical challenges of green hydrogen have been resolved for several years and the largest impediment is state government public service agencies protecting themselves by making disingenuous arguments about reducing carbon emission through “direct action”. Its a government failure. time for public servants to step aside and advertise for a “free market” to address the government failure

  5. Geoff Little 1 week ago

    What is the theoretical energy required for breakng the water molecular bond? Is the simple answer, the equivalent value of the energy released by re-forming the bond? The difference is the relative efficiency of each of the processes surely. If we can achieve a 41% te with a fuel cell, an equivalent on the other side of the equation, that would be useful. Dont know, way above my paygrade, but not inconceivable that either incremental or breakthrough in approaching the theoretical limit will be discovered for both breaking and reforming the molecular bond. Either that or pipe the hydrogen from Jupiter.

  6. Daniel Williams 1 week ago

    Another important aspect is variable electricity pricing. By combining a gas network connection and an electric grid connection (which usually will have significant capacity constraints), a low price for electricity provided to electrolysers can be achieved. This is what is planned in the Netherlands at the moment. It means a €40/MWh electricity price equates to €20/MWh off-peak. The electricity price going to the grid is higher; but half (possibly) the cost of a renewables plant is the electricity infrastructure. So you have no problems, and a stable output, regulated by the use of electrolysers. Its really simple but I think this is the only way to achieve a low hydrogen price. The difficulty lies with what to do with the hydrogen. A hydrogen gas grid is really the answer here, but thats some way off. I’d say industry, or gas turbines.

    The point is that really low hydrogen prices can be achieved.

  7. Ant.. 1 week ago

    In Australia the holy grail for every class of generator is storage. The AEMO reports that at full demand we currently have approximately 23% surplus capacity that represents a loss of opportunity cost.

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