Léonard’s article about the mechanistic details of semiconductor–enzyme hybrid photosystems was published in Trends in Chemistry (read his paper here). The paper highlights exciting work from the Dukovic group at Boulder that examines the various competing electron transfer pathways in biophotocatalysts that are unobservable by direct means. Using kinetic modelling, the work shows how often overlooked pathways such as back electron transfer and reverse reactions are key for achieving a high activity (read original paper here).