Metal quantum clusters: a novel paradigm in catalysis beyond nanomaterials

Sou a: Inici / Actualitat / AGENDA / Esdeveniments Públics d'ALBA / Metal quantum clusters: a novel paradigm in catalysis beyond nanomaterials
Prof. M. Arturo López–Quintela. Research Technological Institute, NANOMAG. University of Santiago de Compostela
Què
events
Quan
Nov 04, 2016
de 15:30 a 16:30 (Europe/Madrid / UTC100)
On
ALBA Synchrotron, Maxwell Auditorium
Nom de contacte
Telèfon de contacte
+34 93 592 43 89
Assistents
If you are interested in attending and you are not ALBA staff, please contact Inma Hernández (ihernandez@cells.es ) with your Identity Card number and name to obtain the ALBA access.
URL de l'esdeveniment
Lloc web relacionat
Afegeix un esdeveniment al calendari
iCal

Abstract

Metal atomic quantum clusters (AQCs), formed by a small number of metal (0) atoms ( < 100-150 atoms), and with sizes below ≈ 1-2 nm, represent a novel state of matter located between classical bulk (or nanoparticles) and single atoms. Due to the strong quantum confinement, they present new and fascinating properties like luminescence, magnetism, circular dichroism, etc. One of the key properties of AQCs is the presence of a band gap at the Fermi level, so they can be considered to be a completely new type of atomic level semiconductors (SCs). Moreover, the value and position of the band gap (HOMO-LUMO gap) can be fine tuned just by changing the cluster size and the metal, opening unprecedented possibilities in the SC area.

In the last decade, a large number of chemical methods have been developed to synthesize AQCs, mainly based on the use of protecting ligands, being thiols the most used ones. However, for many applications, such as catalysis, clusters can be poisoned by the presence of such capping ligands. In the last years we have developed simple techniques, based on kinetic control, to synthesize small AQCs without any surfactant or capping agents. In this talk we will explain the background of such techniques and their application to prepare AQCs with sizes down to 2 or 3 atoms. We will then explain the reasons for the surprisinglylarge stability of clusters and discuss the main advantages of using such clusters in different fields, like catalysis, sensors and biomedical applications. Special emphasis will be given to the different chemistry, which seems to appear at this nanometric/sub-nanometric range of the matter.

References

Y. Attia et al. Gold nanorod synthesis catalysed by Au clusters Faraday  Discuss. 2016, 191, 205-213.

S. Huseyinova et al. Synthesis of highly stable surfactant-free Cu5 clusters in water J. Phys.Chem.C, 2016, 120, 15902-15908.

M. Cuerva et al. Self-Assembly of Silver Metal Clusters of Small Atomicity on Cyclic Peptide NanotubesACS Nano2015, 9, 10834-10843.

D. Buceta et al. Ag2 and Ag3 clusters: synthesis, characterization and interaction with DNAAngew. Chem. Int. Ed. 2015, 54, 7612-6.

N. Vilar-Vidal et al. Green Emitter Copper Clusters as Highly Efficient and Reusable Visible Degradation Photocatalysts.Small 2014, 10, 3632-3636.

Y. A. Attia et al. Structure-Directing and High-Efficiency Photocatalytic Hydrogen Production by Ag Clusters. J. Am.Chem.Soc. 2014, 136, 11821185.

A. Corma et al. Exceptional oxidation activity with size-controlled supported gold clusters of low atomicityNat. Chem. 2013, 5, 775–781.

arxivat sota: