Divergence Between Activity Metrics and Mechanistic Interpretability in Anchored Molecular Electrocatalysts

Abstract

Anchoring molecular electrocatalysts to conductive supports can preserve nominal molecular identity while modifying interfacial behaviour. As a result, commonly reported activity metrics do not necessarily reflect the operative molecular state after immobilization. Here, we analyse 157 reported base-metal systems spanning hydrogen evolution, oxygen evolution, and photoelectrochemical reactions to examine how catalytic activity relates to interfacial effects and the completeness of reported characterization. The analysis shows that systems with similar electrochemical performance can differ substantially in mechanistic interpretability. These variations are a consequence of anchoring-induced perturbations and the completeness of reported characterization. The trends are observed across reductive, oxidative, and photochemical regimes. This work provides a practical basis for evaluating when reported activity can be reliably associated with molecularlevel behaviour in anchored electrocatalysts.