The oxygen evolution reaction (OER) is a chemical process that leads to the generation of molecular oxygen. This reaction is of key importance for the development of clean energy technologies, including water electrolyzers, regenerative fuel cells and rechargeable metal-air batteries.

The extent to which this reaction occurs has so far been limited in many materials, which has restricted the conversion efficiency of some types of energy technologies. Materials scientists have thus been trying to identify alternative materials, including metals, metal oxides and hydroxides, that could be used as electrocatalysts to fuel this reaction. The materials identified so far, however, are far from ideal for large-scale implementation, as they are either not particularly resistant or too expensive.

A class of materials widely investigated as possible electrocatalysts for the OER are metal-organic frameworks (MOFs), hybrid and crystalline compounds that consist of a regular array of positively charged metal ions surrounded by organic molecules. While these materials have promising catalytic properties, scientists have yet to identify optimal strategies to enhance their performance.