RMIT Researchers Discover a Game-Changing Method for Producing Hydrogen From Seawater

Hydrogen is acclaimed as a clean fuel alternative to fossil fuels and therefore a potential solution to critical energy problems, especially in industries such as aviation, manufacturing, and shipping, where eliminating carbon dioxide emissions are a massive challenge. However, its high production costs and dependence on freshwater (or desalinated seawater) have hindered its widespread adoption. That is, until now.

RMIT University has developed a world-changing method for producing hydrogen that excels all other known methods in three major ways: it produces lower carbon dioxide emissions, requires less energy, and costs less financially.

Hydrogen can be produced by splitting water molecules into their components (hydrogen and oxygen) through electrolysis. Splitting fresh water (derived by desalinating seawater) is too financially expensive to be commercially viable, accounting for only 1% of the total global hydrogen produced. Splitting saltwater, however, produces massive amounts of toxic, eye-watering chlorine. At least, it used to.

RMIT’s multidisciplinary Materials for Clean Energy and Environment (MC2E) research group has developed a catalyst that works with seawater. PhD student Suraj Loomba’s research focuses on the production of efficient and stable catalysts that can be produced at a low financial cost. The group has filed a provisional patent application for the method.

According to lead researcher Dr. Nasir Mahmood, RMIT’s Vice-Chancellor Principal Researcher, “If we were to meet the world’s needs for hydrogen without solving this [chlorine production] problem first, we would produce...three or four times more than the world needs chlorine. Our process not only removes carbon dioxide, but also produces no chlorine.” Mahmood also emphasized that in order to be sustainable, hydrogen must be 100% free from carbon dioxide emissions throughout its production life and must not deplete the world’s ever-decreasing freshwater bodies.

RMIT’s groundbreaking method of producing hydrogen straight from seawater is simple, scalable, and far more cost-effective than any other known hydrogen production method. Mahmood claims that further development of this method could lead to a booming green hydrogen industry in Australia. “While other experimental catalysts have been developed for seawater splitting, they are complex and difficult to scale. Our approach focused on modifying the internal chemistry of the catalysts using a simple method that makes their large-scale fabrication relatively easy, so they can be easily synthesized on an industrial scale,” Mahmood reported.

The technology behind this new method promises to significantly reduce the cost of electrolyzers, and will likely contribute to the Australian government’s goal of sustainably producing hydrogen at $2 per kilogram. New research is pointing to a prototype electrolyzer that combines multiple catalysts to produce hydrogen at massive scale.

Reference paper: Suraj Loomba, Muhammad Waqas Khan, Muhammad Haris, Seyed Mahdi Mousavi, Ali Zavabeti, Kai Xu, Anton Tadich, Lars Thomsen, Christopher F. McConville, Yongxiang Li, Sumeet Walia, Nasir Mahmood. Nitrogen‐Doped Porous Nickel Molybdenum Phosphide Sheets for Efficient Seawater Splitting. Small, 2023; 2207310 DOI: 10.1002/smll.202207310

Source article: https://www.rmit.edu.au/news/all-news/2023/feb/hydrogen-seawater