Scientists Successfully Split Seawater To Produce Green Hydrogen

An multinational team lead by Professor Shizhang Qiao from the University of Adelaide and Associate Professor Yao Zheng from the School of Chemical Engineering effectively divided saltwater without pre-treatment to generate green hydrogen.

Professor Qiao stated, "We have electrolyzed natural seawater to make green hydrogen with approximately 100% efficiency, using a non-precious and inexpensive catalyst in a commercial electrolyser."

Cobalt oxide is a common non-precious catalyst that has chromium oxide on the surface.

We utilized saltwater as a feedstock without requiring any pre-treatment procedures, such as reverse osmosis desolation, purification, or alkalization, Associate Professor Zheng said. A commercial electrolyser using our catalysts performs almost as well in saltwater as one using platinum/iridium catalysts with a feedstock of deionized water that has undergone extreme purification.

"Current electrolysers are operated with exceptionally pure water electrolyte," Professor Zheng continued. Freshwater supplies are becoming increasingly scarce, and increased demand for hydrogen to partially or completely replace energy produced by fossil fuels will dramatically worsen this situation.

Seawater is regarded as a natural feedstock electrolyte and is a nearly limitless supply. This makes more sense in areas with extensive coasts and lots of sunshine. It cannot be used in areas with limited access to saltwater, though.

Due to corrosion caused by employing saltwater and electrode side reactions, seawater electrolysis is still in its infancy when compared to pure water electrolysis.

According to Zheng, "traditional electrolysers, including desalination and deionization, always need the treatment of unclean water to a degree of water purity, which raises the operating and maintenance costs of the processes." "Our study offers a way to directly utilize saltwater without the need for pre-treatment systems and alkali addition, which displays equivalent performance to that of the existing metal-based mature pure water electrolyser."

The group will seek to scale up the system using a bigger electrolyzer so that it may be utilized in industrial operations like ammonia synthesis and hydrogen production for fuel cells.


If this research is replicated and is successful, it will be a breakthrough. There are no pricey precious metals used. Cobalt, however, is not that uncommon but is far from plentiful and is frequently obtained from ore that is gathered by young children. As a result, predicting the future of cobalt is quite difficult. Should this study be successful, cobalt prices would rise dramatically and demand would skyrocket. There is cobalt to be gotten; it's only hidden behind "not in my backyard" and the legal restrictions put up by environmental green organizations, which significantly clog up politics.

The absence of discussion of the power source is the second issue. The input vs. product computation isn't demonstrated or addressed, despite the fact that the energy input is unquestionably electric and the claim of efficiency is close to 100%.

However, there is a lot of excitement about the idea of a far lower water supply cost and the avoidance of precious metals. A hearty congratulations to the group is due. Let's hope the next phases can be completed with little expense and without needing years of political wrangling.

By Brian Westenhaus via New Energy and Fuel