The concept of single-site or single-atom catalysis is often referred to as systems where individual hetero-atoms are immobilized on a given substrate surface and rightly finds itself at the intersection of proper homogeneous catalysis and proper heterogeneous catalysis seeking to combine the advantages of both fields while addressing their drawbacks.
In this project, we apply the concept of heterogeneous single-metal-site catalysis to the contemporary challenges of heterogeneous photocatalysis by controllable modification of photocatalyst surface with atomically sized co-catalyst species, understanding the interaction with the support and unraveling their performance towards photocatalytic water splitting and CO2-to-fuel reactions.
Our work on the design of noble-metal-free co-catalysts (see section above) further serves as a platform for developing the concept of single-site photocatalysis: to this end, we employ the so-called site-isolation strategy and develop adsorption-limited impregnation protocols aiming to downscale the co-catalyst species exemplifying the most promising earth-abundant Cu and Ni as well as noble Pt and Au systems. Our first publication , opens an external URL in a new windowdemonstrates a strong impact of the substrate surface modification (e.g. with inorganic acids) on the co-catalyst deposition and structure and reveals a strong increase of HER TOF values – corresponding to more single, isolated sites – when lower co-catalyst loadings are used.