Transition metal oxide nanoparticle electrocatalysts for the oxygen evolution reaction (OER) - Challenges in synthesis and shape control

The increasing demand of renewable energy, and the desire to reduce atmospheric levels of CO2, require efficient catalysts for energy conversion processes. Electrochemical water splitting to generate O2 and H2 – where the goal is to use the released electrons to drive CO2 electroreduction – offers a path to a closed “net-zero” emission cycle. Amongst the most active catalysts for the sluggish anode half reaction, the oxygen evolution reaction (OER), are binary combinations of mixed Ni-Fe electrocatalysts. The OER activity on well-defined oxide surfaces such as Ni-Fe nanoparticles have so far not been extensively explored. Here we present a path to highly crystalline Ni-Fe nanocatalysts extended to the series of 3dtransition metals.