The organic molecule Quinone has been altered to enable Cobalt based catalysis of clean hydrogen fuel. The new method has yet to rival the output of contemporary fuel cells but has managed to reduce the cost for output that it can generate.
Fruther efforts to improve the output could eventually lead to the replacement of platinum based catalysis, changing the way companies like Amazon and Home Depot run their warehouses to support a more environmentally positive approach
Published in the journal “Joule” the study was conducted by professor Shannon Stahl and Thatcher Root from the University of Wisconsin-Madison
In Hydrogen fuel cells electrons and protons are transported from one electrode to another. During which they combine with Oxygen atoms in the air to create water (Hydrogen DiOxide). When atoms fuse or detach they release chemical energy that can be harnessed by electrodes to create electricity.
However in order for this to work properly the reactions must reach a certain critical speed, so a chemical catalyst is used to speed up the process- special molecules that are capable of hastening a particular reaction. Different catalysts are used for different reactions. In this case platinum is the best catalyst, unfortunately platinum is very expensive, which is why there aren’t very many hydrogen fuel cells. Furthermore, less expensive catalytic metals can only be used in large quantity
“The problem is, when you attach too much of a catalyst to an electrode, the material becomes less effective,” he says, “leading to a loss of energy efficiency.”
So what they did instead was fill a nearby reactor with some inexpensive cobalt and then by shuttling particles back and forth between the new reactor and the old fuel cell they were able to circumvent the previous load limit. A strategy of compartmentalization to prevent the cobalt from over-loading electrodes.
In order to accomplish that they needed to find a carrier molecule for the electrons and protons to hitch a ride on. So they decided to try out a completely organic ultra-stable quinone derivative. Quinone would otherwise deteriorate after only a few cycles but the team was able to modify it’s structure to endure 100 times more, making the new method a viable alternative to platinum catalysis.
“While it isn’t the final solution, our concept introduces a new approach to address the problems in this field,” says Stahl.
The new design has an output that reaches about 20 percent of whats possible with contemporary hydrogen fuel cells. Though it has yet to compete with traditional forms of hydrogen based energy extraction it is still 100 times more effective than any other bio-fuel cell.
Next they will search for a way to improve Quinone shuttle molecules so that they match conventional fuel cells at a cheaper price.
“The ultimate goal for this project is to give industry carbon-free options for creating electricity,” says Colin Anson, a postdoctoral researcher in the Stahl lab and publication co-author. “The objective is to find out what industry needs and create a fuel cell that fills that hole.”
“In spite of major obstacles, the hydrogen economy seems to be growing,” adds Stahl, “one step at a time.”