A mechanical, high surface area and solvent-free 'powder-to-electrode' fabrication method for screening OER catalysts

The screening of new OER materials routinely involves fabricating electrodes from powders using methods which are often time consuming and may involve using solvents and/or conductive materials that can alter the OER activity of the powder. Herein, a new mechanical, solvent-free method for fabricating electrodes for OER is described in which a electroactive material under test, mixed with a small amount of PTFE powder (ca. 10 wt%), is pressed onto Pt powder to create a permanent, robust electrode that can be used in a rotating disc electrode set-up. This new method of fabricating electrodes is compared to the well-known dropcast on Glassy Carbon (GC) method, using commercially available materials: RuO2, Co3O4 and NiO. The results show that the mechanical route produces much better OER performances, in terms of overpotential and stability, for the commercial metal oxide on the pressed discs when compared to the dropcast GC method. Finally, it is shown that this mechanical, high surface area, solvent-free electrode fabrication technique can also be achieved using silver, rather than platinum, as the conducting, support material.