Materials chemistry

Electrocatalysts (HER, OER, ORR)

Study how surfaces accelerate hydrogen evolution, oxygen evolution, and oxygen reduction, and how activity descriptors, intermediates, stability, and benchmarking define electrocatalytic performance.

IntuitionMaking electron transfer efficient

The HER supplies H₂, the ORR consumes O₂ in many fuel cells, and the OER evolves O₂ in water splitting. The same electrode potential can give very different currents depending on the catalyst surface, its intermediates, and the available active area.

SchoolHalf-reactions and overpotential

HER proceeds through adsorbed hydrogen intermediates with pathways such as Volmer–Heyrovsky or Volmer–Tafel. In alkaline ORR, oxygen can follow four-electron or partial two-electron routes. OER requires sequential oxidation of water or hydroxide through surface oxygen species.

UndergraduateDescriptors and kinetics

A good HER catalyst binds H neither too weakly nor too strongly; ORR and OER depend on adsorption energies of OH, O, and OOH or related species. Scaling relations can link those energies. The rate-determining step depends on surface, electrolyte pH, and experimental conditions, so a single Tafel slope alone does not identify a mechanism universally.

AdvancedMicroscopic mechanism and active sites

Computed free-energy diagrams test intermediates at finite potential, while experiments probe rotating-disk currents, electrochemical impedance, isotope effects, and operando spectroscopy. Catalysts may reconstruct under bias; the measured active surface can differ from the synthesized structure, and stability or dissolution may cap practical lifetime.

ResearchResearch frontier