Hydrogen Fuel Cells
PGMs are excellent catalysts that make chemical reactions take place at higher speed, at a lower temperature, and at higher rates of conversion. One key growth area of PGM catalysts as we shift towards a post carbon technologies, is in fuel cells.
Fuel cells produce electricity by combining hydrogen fuel with ambient oxygen over a catalyst. The high efficiency of fuel cells make them suitable for powering vehicles, but also as back up power generators to produce electricity during electricity grid failure. Fuel-cells operate silently like batteries because they have no moving parts and are inherently more efficient than combustion engines, by using an electrochemical reaction to generate power. They require no recharging and will run indefinitely when supplied with fuel.
The most researched type of fuel cell is the proton exchange membrane (PEM) fuel cell, which uses PGM-containing catalysts in their electrodes - namely Platinum and Ruthenium.
The porous catalyst is coated with platinum nanoparticles to maximise the surface area which will come into contact with hydrogen and oxygen, and a small amount of Ruthenium protects the catalyst from poisoning by trace carbon monoxide in hydrogen fuel.
Although hydrogen fuel can be produced via various technical processes, currently electrolysis seems the most promising option, which uses electricity to split water into hydrogen and oxygen in an electrolyser. For hydrogen fuel cell technology to be truly sustainable, this electricity used to produce hydrogen fuel should come from renewable sources, such as wind power.