Award Lecture, Invited / Award Lecture

Mechanistic insights into the formation of Cu nanocrystals pave the way towards better catalysts to reduce CO2

R. Buonsanti1
1Department of Chemical Sciences and Engineering, École Polytechnique Fédérale de Lausanne, CH-1950 Sion

The chemistry of non-noble metal nanocrystals (NCs) is far less advanced compared to noble metals. Yet, tuning their composition, size and shape is important for various applications, spanning from plasmonics to catalysis.

In this talk, I will present our recent group efforts towards the synthesis via colloidal chemistry of Cu NCs and Cu-based NCs.

First of all, I will focus on our studies on nucleation and growth. A fundamental understanding of the formation mechanisms is indeed crucial to rationally approach the design of new or underexplored classes of materials. Here, in-situ investigations by X-Ray spectroscopies and scattering allowed us to identify the key reaction intermediates and to direct the growth towards shaped-controlled Cu NCs.

I will then illustrate how these NCs can help to identify selectivity rules at the branching nodes which lead to C1 and C2+reduction products in the challenging electrochemical CO2 reduction reaction. I will conclude by sharing our latest results which illustrate that the above discussed catalysts are not only model systems but can be implemented in a gas-fed electrolyzer and sustain the same selectivity at technologically relevant conditions with currents up to 300 mA/cm2.