Measuring reaction rates for heterogeneous catalysis

Heterogeneous catalysis on solid surfaces provides high value chemicals and is involved in a large fraction of the world’s economic productivity, yet our understanding of this important class of processes remains limited. Thermal reaction rates obtained from experiments on model cata-lysts provide quantitative data that can reveal reaction mechanisms and provide benchmarks for computational simulations of catalytic processes. This perspective describes a critical ad-vance in measuring these rates: Velocity Resolved Kinetics (VRK). VRK delivers absolute rates for elementary surface reactions that are of sufficient accuracy that they may be meaningfully com-pared to theoretical rate predictions, creating a powerful synergy between theory and experi-ment. It is now routinely possible to derive fundamental thermochemical quantities including: desorption and adsorption energies, reaction barrier heights, diffusion barrier heights and lateral adsorbate interaction energies. Reaction mechanisms can also be revealed and reaction interme-diates directly detected. The high time resolution of VRK allows study of catalytic reactions at the high temperatures typical of conditions present in real catalytic reactors. Current work exploit-ing the newest and by far most powerful variant of VRK has only scratched the surface of what is possible, signifying a promising future for researchers in this field.