Researchers have successfully split seawater into green hydrogen without pretreatment.
The international team was led by Professor Shizhang Qiao from the University of Adelaide and Associate Professor Yao Zheng from the Department of Chemical Engineering.
“We split natural seawater into oxygen and hydrogen with nearly 100% efficiency, and produced green hydrogen by electrolysis using non-precious and inexpensive catalysts in commercial electrolyzers,” said Professor Qiao. said.
A typical non-noble metal catalyst is cobalt oxide with chromium oxide on the surface.
“We used seawater as a raw material without the need for pretreatment processes such as reverse osmosis devastation, purification, and alkalinization,” said Associate Professor Zheng.
“The performance of commercial electrolysers using our catalysts operating in seawater approaches the performance of platinum/iridium catalysts operating with highly purified deionized water feedstock.
Our work provides solutions that utilize seawater directly without pretreatment systems or alkali additions. It exhibits similar performance to existing metal-based mature pure water electrolysers.Yao Zheng, associate professor and chemical engineering researcher at the University of Adelaide.
The team published the study in the journal natural energy.
“Current electrolysers operate with highly purified water electrolytes. It greatly increases the scarcity of resources.”
Seawater is an almost unlimited resource and is considered a natural raw electrolyte. This is more practical in areas with long coastlines and abundant sunlight. However, it is not practical in areas where seawater is scarce.
Seawater electrolysis is still underdeveloped compared to pure water electrolysis due to electrode side reactions and corrosion resulting from the complexity of using seawater.
“It is always necessary to treat impure water to the water purity level of traditional electrolyzers, including desalination and deionization, which increases the cost of operating and maintaining the process,” said Zheng. .
“Our work provides a solution that utilizes seawater directly without pretreatment systems or alkali additions, which performs similarly to existing metal-based mature pure water electrolysers.”
The team is working to scale up the system with a larger electrolyser for use in commercial processes such as hydrogen production in fuel cells and ammonia synthesis.
Original: Generating Green Hydrogen by Decomposing Seawater
Than: University of Adelaide
