Complex oxide catalysts are commonly employed in many important catalytic reactions. However, determining how different structural motifs affect the activity and selectivity is difficult to decipher under realistic reaction conditions, leading to a need for model studies. Here we employ a simple sublimation of oxides to deposit monodispersed (MgO)1 monomers and (MoO3)3 trimers on anatase TiO2(101) and prepare well-defined model systems with different acid-base and redox properties. A combination of atomically resolved imaging, surface-sensitive spectroscopies, and theoretical calculations is used to characterize the cluster structure and binding as a function of coverage and deposition and annealing temperatures. While (MgO)1 monomers are readily immobilized at room temperature, (MoO3)3 diffuse and agglomerate. The mobility of (MoO3)3 allows for the formation of an ordered overlayer on TiO2(101). Both types of clusters are thermally stable making them ideal for model reactivity studies. At elevated temperatures, (MgO)1 diffuses into the TiO2 bulk, while (MoO3)3 remains on the surface, but becomes reduced and disordered. To probe the acid/base and redox properties of such systems we use small aliphatic alcohols to follow the competition between the dehydration and dehydrogenation channels as a function of alkyl chain length and number. Such well-defined systems allow us to uncover how different structural motifs control catalytic activity.

Monodispersed (MgO)1 and (MoO3)3 clusters on anatase TiO2(101) for model catalytic studies

Macromolecular Chemistry: The Second Century

[Author Benefits](https://scimeetings.acs.org/?utm_source=pubs_content_marketing&utm_medium=website&utm_campaign=0320_MCF_NPI_Launch_Spring_Homepage&ref=pubs_content_marketing)

[How to use SciMeetings](https://storage.googleapis.com/dl.morressier.com/acs/SciMeetings-ACSSpring2020-HowToGuide_M3020-Final.pdf)

[Frequently Asked Questions](https://storage.googleapis.com/dl.morressier.com/acs/SciMtng_ACSNMSp2020_FAQ_M3120_Final.pdf)

ACS Spring 2020 National Meeting & Expo

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.