Study of the mechanism of nucleation of platinum nanoparticles through X-ray absorption spectroscopy using a continuous flow microfluidic device

Authors: Sylvia Britto (Diamond Light Source) , Christopher Parlett (Diamond Light Source; The University of Manchester at Harwell) , Stuart Bartlett (Diamond Light Source) , Konstantin Ignatyev (Diamond Light Source) , Sven L. Schroeder (Diamond Light Source; University of Leeds)
Co-authored by industrial partner: No

Type: Conference Paper
Conference: XAFS2021
Peer Reviewed: No

State: Published (Approved)
Published: July 2021

Abstract: Platinum nanoparticles exhibit unique catalytic properties and have a number of important applications: as an industrial catalyst for fuel cells, in the synthesis of nitric acid, as well as in the reduction of exhaust gases from vehicles. While there have been many studies demonstrating size and morphology control of platinum nanoparticles, a molecular level understanding of the nucleation and growth mechanisms underlying nanoparticle formation, which is crucial for efficient optimization of size controlled synthesis, is lacking in the literature. Structurally incisive experimental in situ probes with enough spatial and temporal resolution are needed to monitor nucleation and growth processes. Here we use operando X-ray Absorption Spectroscopy (XAS) coupled with continuous flow microfluidics to study the mechanisms of platinum nanoparticle formation by reduction of H2PtCl6 using ethylene glycol as a reducing agent. In contrast to a batch synthesis, a continuous flow device allows for rapid and efficient mixing of precursors and fine control over the synthesis parameters such as concentration, flow rate and temperature. The XAS results capture the intermediate stages of nanoparticle formation through to complete reduction to Pt nanoparticles. The setup described here can, in principle, be used to study nanoparticle nucleation and growth mechanisms of a wide range of nanoparticles that occur at fast (microsecond) timescales.

Subject Areas: Materials, Chemistry

Instruments: I18-Microfocus Spectroscopy

Added On: 09/08/2021 13:27

Discipline Tags:

Physical Chemistry Catalysis Chemistry Materials Science Nanoscience/Nanotechnology

Technical Tags:

Spectroscopy X-ray Absorption Spectroscopy (XAS)