Tuning the Catalytic Activity of Oxide-Supported Nanoparticles via Plasma-Assisted Synthesis
- Alina Vlad (Synchrotron SOLEIL, France)
- Wednesday 1 April 2020
- Hotel NH Noordwijk Conference Centre Leeuwenhorst
Rational design of tomorrow’s catalytic nanomaterials requires the knowledge of “atomic construction rules”, i.e., how catalyst structures are linked to optimized activity and selectivity for a particular reaction. An approach to find this mapping is to use model systems whose complexity approaches to that of real catalysts, both in terms of structure and working environment, yet are amenable for controlled experimental testing and verification. Metal nanoparticles supported on well-defined oxide surfaces are one of such prototype systems, as they mimic real catalysts at the nanoscale. The activity of the nanocatalysts is related to their size, shape, composition, dispersion, and the nature of the supporting oxide substrate.
In this work, we have prepared 3 and 5 nm Pd nanoparticles supported on oxide substrates using micelle nanolithography, i.e., a self-assembly technique that makes use of reverse micelles and plasma exposure in order to produce ordered arrays of supported-nanoparticles with controllable size and interparticle distance. Using the diffraction-compatible flow reactor (Leiden Probe Microscopy, The Netherlands) at the SixS beamline (Synchrotron SOLEIL, France), we have investigated the structure - activity relationships of Pd nanoparticles during the CO oxidation reaction and C2H4 hydrogenation via operando grazing incidence x-ray scattering coupled with mass spectrometry measurements. In addition, we have performed systematic in situ studies of the oxidation and reduction behavior of the nanoparticles. Our experimental results show that by a rational change of the synthesis procedure, we can control the reactivity of the nanoparticles.
Synchrotron SOLEIL, L’Orme des Merisiers, Saint-Aubin, F-91192 Gif-sur Yvette, France