Colloidal nanocrystals to advance catalysis and energy technologies

Speakers: Professor Raffaella Buonsanti, École Polytechnique Fédérale de Lausanne

Affordable clean energy and climate action are two of the sustainable development goals set by the United Nations to be achieved by 2030. The vast majority of energy technologies relies on nanomaterials and their progress is strongly connected to the ability of material chemists to tune their property and function-dictating features (i.e. size, composition, composition, morphology).
In this talk, I will present our recent group efforts towards the synthesis via colloidal chemistry of atomically defined nanocrystals (NCs) with properties of interest for catalysis and energy conversion.
The first part will focus on our studies on the synthesis development and formation mechanism of Cu NCs. I will illustrate how these NCs with precisely tunable shapes, sizes and interfaces serve as ideal platforms to advance our current knowledge towards improved selectivity in the electrochemical CO2 reduction reaction. I will then share our results evidencing that these NCs can sustain their catalytic activity and selectivity at technologically relevant conditions, therefore might also offer practical solutions.
The second part will be dedicated to our colloidal atomic layer deposition (c-ALD) method to grow hybrid materials including NCs surrounded by an oxide shell embedding organic ligands. The oxide shells confer the NC with improved stability and enable further functionalization and post-processing. I will discuss the formation mechanism of the shell by sharing our insight into the surface chemistry. I will then present how we manipulated the growth process in order to incorporate photoactive ligands around semiconductor NCs to create funnel structures with potential applications as photocatalysts and sensitizers for incoherent photon conversion.