The new research comes from Stanford University. In a trial for the new technology, the scientists were able to generate hydrogen fuel using a combination of solar power, electrodes and saltwater drawn from the San Francisco Bay.
Hydrogen offers a clean energy solution, where power is produced by splitting water into hydrogen and oxygen. Hydrogen fuel is a zero-emission fuel when burned with oxygen. The fuel can be used for several processes, such as for electrochemical cells or internal combustion engines to power vehicles or electric devices.
The new process offers a more environmentally-friendly alternative to fossil fuels. However, most processes rely on the use of water that has gone through a purification process, which is necessary to remove salts. The process of water purification is expensive and the process itself can have an environmental impact. For this reason, the research team looked at the use of seawater, which can be collected and processes without the need for pre-treatment.
The reason why the process could not be attempted before was because negatively charged chloride in seawater salt can corrode the positive end of an electrode (the anode), which limits the lifespan of nay hydrogen generation system.
The researchers overcame the electrode issue by coating the anode with special layers of material rich in negative charges (nickel-iron hydroxide). These layers were shown to repel chloride and to slow down the decay of the underlying metal, making the electrodes last for long periods time. This means that the new technology has the potential for scale-up.
Through the process, the science group were able to conduct up to ten-times more electricity through the new multi-layer device, meaning the generation of hydrogen from seawater occurred at a faster rate and that greater quantities of seawater could be processed through the prototype.
The new research has been published in the journal of the Proceedings of the National Academy of Sciences. The research paper is titled “Solar-driven, highly sustained splitting of seawater into hydrogen and oxygen fuels.”
