ME4OER · Mechanism Engineering of the Oxygen Evolution Reaction

I propose innovative strategies to elucidate and engineer the electrocatalytic mechanism of earth-abundant transition metal oxides with the aim of enhancing the low efficiency of the oxygen evolution reaction (OER). Mastering multi-electron reactions such as the OER is critical for the transition from dwindling fossil fuels to ecologically and economically sustainable fuels based on renewable energy. Water is the most abundant source of hydrogen bonds on earth and fuels based on these bonds have the highest energy densities, which makes water an attractive resource for sustainable fuels production. However, the production of any hydrogen-based fuel from water is currently thwarted by the low efficiency of the OER. Improved catalysts are presently designed by optimizing a single step in the reaction sequence. In contrast, I target the low efficiency of the OER by engineering multiple steps of the mechanism to (i) control the number of electron transfers before the limiting step; and (ii) enforce a reaction path close to the thermodynamic limit. Combining these two strategies increases the catalytic current of transition metal oxides at typical overpotentials by a factor of 100,000. Rational design of the mechanism on this fundamental level calls for unprecedented insight into the active state of electrocatalysts. My team will achieve this firstly by novel approaches to prepare catalytically limiting states for their elucidation by synchrotron-based X-ray spectroscopy and secondly by studying transitions between these states in pioneering time-resolved experiments. Both the required breakthroughs in method development and the innovative scientific strategies are generalizable to other multi-electron reactions, which opens the door for industrial catalysts that store energy sustainably in hydrogen-based fuels on a global scale.