Contemporary alchemy: conferring noble-metal reactivity on cheap elements by ligand design

Samenvatting

Catalysis plays a key role in the conversion of raw materials to the products that we use in our daily life. A large part of catalytic processes used in industry rely on precious (or 'noble') metals that are scarce, expensive and raise concerns due to toxicity when retained in the final product. Replacing these elements with base metals or main group elements that are more abundant and benign is thus highly desirable: successful implementation has the potential to completely reshape the catalysis landscape.

The prevalence of catalysts based on precious metals is due to their versatile electronic properties that allow redox-reactions in discrete 2-electron steps. Base metals, on the other hand, generally prefer 1-electron (radical) chemistry that lacks selectivity. For main group elements, reactions that involve redox chemistry are uncommon because these often have only one accessible oxidation state. A primary challenge in catalysis is therefore: how can the favourable catalytic properties of precious metals be replicated to cheap elements?

In response to this challenge my research program aims to develop a strategy that confers noble-metal reactivity on cheap and abundant elements by making use of ligands that are redox-active: i.e., the organic ligand framework participates in redox-reactions.

This proposal is built on my recent discovery of formazanates as easily accessible redox-active ligands. I will use an integrated synthetic and computational approach to develop catalysts based on non-scarce elements that use the tunable redox-chemistry of formazanate ligands to emulate noble-metal properties. The proposal is comprised of two parallel and complementary strands:

- Efficient base metal catalysts for CO2 reduction at low overpotentials

- Main group catalysts that perform oxidative addition / reductive elimination reactions

The overall goal of this project is to replace precious metals by earth-abundant and inexpensive elements, thereby contributing to greener catalysis and a sustainable society.

Producten

Wetenschappelijk artikel

Kenmerken

Projectnummer

723.014.004

Hoofdaanvrager

Dr. E. Otten

Verbonden aan

Rijksuniversiteit Groningen, Faculteit B├Ętawetenschappen en Technologie (FBT), Stratingh Instituut voor Chemie

Uitvoerders

F. Milocco, R. Mondol MSc, Dr. E. Otten

Looptijd

01/09/2015 tot 01/09/2020