Producing 'Green' Hydrogen Through Seawater Split

Researchers have successfully split seawater without pre-treatment to produce green hydrogen. "We used seawater as a feedstock without the need for any pre-treatment processes like reverse osmosis desolation, purification, or alkalization," said Associate Professor Zheng. The team published their research in the journal Nature Energy.

The international team was led by the University of Adelaide’s Professor Shizhang Qiao and Associate Professor Yao Zheng from the School of Chemical Engineering. “We have split natural seawater into oxygen and hydrogen with nearly 100 per cent efficiency, to produce green hydrogen by electrolysis, using a non-precious and cheap catalyst in a commercial electrolyser,” said Professor Qiao.

A typical non-precious catalyst is cobalt oxide with chromium oxide on its surface. “Current electrolysers are operated with highly purified water electrolyte. Increased demand for hydrogen to partially or totally replace energy generated by fossil fuels will significantly increase scarcity of increasingly limited freshwater resources,” said Associate Professor Zheng.

Seawater is an almost infinite resource and is considered a natural feedstock electrolyte. This is more practical for regions with long coastlines and abundant sunlight. However, it isn’t practical for regions where seawater is scarce.