Prof Richard Haverkamp, of Massey University, outlines the role of electrocatalysts in the production of hydrogen from water by electrolysis.
DR RICHARD HAVERKAMP
We’re looking at hydrogen as a new energy carrier, but in order to do that you have to be able to produce the hydrogen and you have to be able to use the hydrogen up. Producing hydrogen by water electrolysis is one way to do it from any electrical energy source. So you might have wave power or wind power, to produce the electricity and you can make hydrogen from water by putting two electrodes into it and putting some salt in there, potassium hydroxide, or sulphuric acid or whatever, and electrolyse it and make hydrogen and oxygen. Now that works perfectly well except that its not very efficient, so you waste a huge proportion of your energy doing it that way. A much better way to do it, is to do it in the cell where we have a catalyst. So rather than just on an electrode, you have a device set up where the reaction takes place on a catalyst and the catalyst enables the reaction to take place easily, without a lot of waste of energy. And this is an electrocatalyst because we‘re using electricity to drive the reaction. A greater proportion of the energy you’re putting in ends up as hydrogen. If you are doing it on a large scale you don't want to waste all your energy, you want to maximise the amount you turn into hydrogen. So we need to have a good electric catalyst for making hydrogen from water. And so we've been working on this material that helps water be converted into hydrogen using electricity in a very efficient way.