Science Buddies: "Ask an Expert"

I have been researching fuel cells for my science project. I have seen fuel cell kits for sale on the internet. My experiment is to test if copper, stainless steel or aluminum would make good anode and cathode materials for PEM fuel cells. Would I be able to test this with the kits? Is it very difficult to build a fuel cell myself?

Hello and welcome to the forums.

Your project seems quite doable. Do you have specific fuel cell kits you are looking at? As long as the kit allows you to exchange the anode and cathode easily and you have the candidate materials (e.g . copper, stainless steel, or aluminium) ready, you should be ready to go.

It seems your focus is on the effect of different materials. Then, you probably want to keep other variables (e.g. shape and size of the anode and cathode, etc.) the same. It might be a good idea to research a bit about how the PEM fuel cell works and what makes a good anode and cathode.

JChang

I have a Horizon fuel cell kit. I can take it apart and substitute my own anode/cathode material. My question now, can I use stainless steel screen? The cathode/anode appear to be a mesh type metal perhaps to allow gas flow. I have checked to hardware stores for aluminum, copper and stainless steel screen material and they carry it.

Hi Adriana,

I read a bit about the "Horizon fuel cell kit." The way I understand it, you will first conduct the electrolysis of water to generate some hydrogen and then use the hydrogen to power the fuel cell. For the fuel cell to work, the hydrogen is delivered to the anode side and is catalytically split into protons and electrons.

According to wikipedia (http://en.wikipedia.org/wiki/Proton_exc ... _fuel_cell),
"Splitting of the hydrogen molecule is relatively easy by using a platinum catalyst. ... One promising catalyst that uses far less expensive materials—iron, nitrogen, and carbon—has long been known to promote the necessary reactions, but at rates that are far too slow to be practical."

So, it looks like that the anode has to be able to catalyze the hydrogen, and not all materials will work. Your experiment will help you understand what materials work.

Also, remember to follow lab safety rules and read all the safety instructions that come with the fuel cell kit to make sure it is safe to open up the fuel cell and replace the anode and cathode. Make sure to have an adult supervise you, too.

JChang

JC,

I have contacted Horizon and they told me I cannot take the fuel cell apart. I am thinking of doing the experiment with coiled wire in water and running a current through it. I know this will split water into hydrogen and oxygen. I have seen this experiment with platinum wire. I will test it with copper, aluminum and stainless steel wire. Right after splitting the water and disconnecting the current, I will test for any current with a voltmeter to see if the reaction works in reverse. Build a fuel cell on my own proved to be expensive and difficult.