Scientists at UNSW Sydney have developed a technique to analyse hydrogen fuel cell stability and are working on ways to improve the efficiency and cost of hydrogen fuel cells.
UNSW School of Chemistry Professor Chuan Zhao, Dr Quentin Meyer and Shiyang Liu are included in the group of scientists trying to increase the commercial viability of hydrogen fuel cells.
Despite playing a huge role in decarbonisation, the commercialisation of hydrogen has been slow.
Some of the causes of this can be accredited to the cost and resources of some of the key elements that make up a hydrogen fuel cell.
This includes platinum, which is commonly used as the catalyst to activate the process.
Therefore, UNSW researchers are looking to create alternatives to these platinum catalysts, which costs between $45,000 to $100,000 per kilogram.
Professor Zhao stated that platinum is always going to be expensive due to how scarce it is.
“We need to explore alternatives, whilst also providing a quick and easy way to measure how well these new materials are working in hydrogen fuel cells,” said Professor Zhao.
Researcher Shiyang Liu has suggested that one approach would be to use alternatives like iron, which costs 10 cents per kilogram — he added that a particularly promising material would include iron-nitrogen-carbon.
Unfortunately, many of these new alternatives are not as widely available as they lack stability when compared to platinum and tend to break down at a faster rate in hydrogen fuel cells.
Dr Quentin Meyer said “While platinum-based fuel cells can last up to 40,000 hours (about four and a half years), the iron-nitrogen-carbon materials can only run up to 300 hours (about two weeks), in a best-case-scenario.
“Progress in the field has been slow, as finding alternatives and testing their durability is a lengthy and expensive process. “For instance, creating a new hydrogen fuel cell catalyst can take up to a year, and then even longer to understand exactly what’s happening using expensive equipment that is hard to access,” said Dr Meyer.
The team at UNSW Sydney is currently trying to develop a method that allows scientist to understand why some catalyst materials are not as stable as platinum.
“Using three novel methods that we tested in the lab, we can quickly figure out how stable our platinum-free fuel cell is and most importantly understand why. This approach can be easily adopted by scientists in other labs to gain quick and accurate insights into the efficiency of their fuel cells and catalysts,” said Professor Zhao.
The team discovered that up to 75 per cent of the iron-based active sites become inactive within the first 10 hours of running the fuel cell because of the loss of iron-active sites.
Carbon corrosion was then shown to take place as it became the predominant degradation mechanism.
“This is particularly significant as we can pinpoint exactly what is happening and when it is happening. If we develop a material that has more stable active sites, we should see a slower decay in the first 10 hours, while carbon corrosion may have a similar trend.
“By allowing precise tracking of the degradation mechanisms, we expect that the research field will be able to make new materials targeting these stability issues. As a result, we believe our approach will help improve the stability of platinum-free catalysts and give this field a brighter future,” said Dr Meyer.
The research team is also prioritising ways to increase the scalability of the affordable platinum-free hydrogen fuel cell catalyst from the lab to a product that can eventually be used as a power source in the future.
Hydrogen is considered to be a clean and sustainable source of energy as it only produces water as a by-product.
Hydrogen fuel cells use chemical reactions to break hydrogen into protons and electrons, which produces electricity and water.
The difference between hydrogen fuel cell technology and batteries is that the fuel cells do not need to be charged up.
