Bimetallic electrocatalysts supported on TiO2 for PEM water electrolyzer

TiO2 was investigated as a support for several multi-metallic electrocatalysts. Particle size distribution from High Resolution Transmission Electron Microscopy (HRTEM) images showed less than 2 nm average particle sizes. For unsupported Ir-Ru, HRTEM images showed nanoparticles closer than supported Ir-Ru on anatase TiO2 that tend to agglomerate. The electrocatalysts supported on anatase TiO2 showed higher activity towards the oxygen evolution reaction (OER) than those supported on rutile TiO2. Overall, Ir-Ru had the highest current per gram of metal than other metal combinations studied and the optimum ratio was 1:1 Ir:Ru. For the unsupported case, the OER activity was about 41% lower than supported.