December 1 - 6, 2024
Boston, Massachusetts
Symposium Supporters
2024 MRS Fall Meeting & Exhibit
CH01.03.03

ALD-Fabricated MgO-Overcoats to Control Sintering of Model Pt Nanoparticle Catalysts—The Power of Synchrotron X-Ray Scattering Tools

When and Where

Dec 3, 2024
9:15am - 9:30am
Sheraton, Third Floor, Hampton

Presenter(s)

Co-Author(s)

Kinanti Aliyah1,Matthias Filez1,Zhiwei Zhang1,Eduardo Solano2,Christophe Detavernier1,Jolien Dendooven1

Ghent University1,ALBA Synchrotron2

Abstract

Kinanti Aliyah1,Matthias Filez1,Zhiwei Zhang1,Eduardo Solano2,Christophe Detavernier1,Jolien Dendooven1

Ghent University1,ALBA Synchrotron2
Nanoparticle sintering is a prime mechanism of catalyst deactivation.[1] During sintering, nanoparticle growth decreases the amount of active surface area for catalytic reaction, leading to performance losses. Amongst the explored design strategies to prevent nanoparticle sintering, partial overcoating of the catalyst surface presents a viable route. Recently, we demonstrated the application of atomic layer deposition (ALD) to deposit sub-monolayer MgO overcoats on model SiO2-supported Pt nanoparticle catalysts to physically prevent sintering, while keeping controlled fractions of the Pt surface available for reaction.[2] The deposited MgO layer can range from sub-monolayers to nm-range and has been proven to exhibit an increase in the onset temperature of sintering.

Herein, we explore synchrotron-based X-ray scattering and diffraction tools to monitor the structural evolution of ALD-fabricated, MgO-overcoated Pt nanoparticles in situ during gas treatments which stimulate sintering. In particular, the MgO-overcoated Pt nanoparticles are subjected to propane dehydrogenation reaction and O2 regeneration cycles at 6000C and compared to their overcoat-free Pt analogues. The real-time Pt nanocrystal size and orientation are respectively probed by complementary in situ grazing-incidence small-angle X-ray scattering (GISAXS)[2, 3] and wide-angle X-ray scattering (GIWAXS)[4] (ALBA synchrotron). In situ GISAXS evidences that the MgO-overcoat leads to a decreased rate of nanoparticle sintering. Surprisingly, complementary GIWAXS data shows that the crystallographic evolution of nanoparticles, and in particular their orientation on the SiO2 support, is strongly influenced by the MgO-overcoat. We therefore anticipate that ALD-tailored partial overcoats not only form a technology to control the sintering rate of nanoparticles, but can also be instrumentalized to direct crystal orientation under harsh post-synthesis processing conditions.

References:
[1] Dai, Y. Q.; Lu, P.; Cao, Z. M.; Campbell, C. T.; Xia, Y. N. The Physical Chemistry and Materials Science Behind Sinter-Resistant Catalysts. Chem Soc Rev 2018, 47 (12), 4314-4331. DOI: 10.1039/c7cs00650k.
[2] Zhang, Z. W.; Filez, M.; Solano, E.; Poonkottil, N.; Li, J.; Minjauw, M. M.; Poelman, H.; Rosenthal, M.; Brüner, P.; Galvita, V. V.; et al. Controlling Pt Nanoparticle Sintering by Sub-Monolayer MgO ALD Thin Films. Nanoscale 2024, 16 (10), 5362-5373. DOI: 10.1039/d3nr05884k.
[3] Dendooven, J.; Ramachandran, R. K.; Solano, E.; Kurttepeli, M.; Geerts, L.; Heremans, G.; Rongé, J.; Minjauw, M. M.; Dobbelaere, T.; Devloo-Casier, K.; et al. Independent Tuning of Size and Coverage of Supported Pt Nanoparticles using Atomic Layer Deposition. Nat Commun 2017, 8. DOI: 10.1038/s41467-017-01140-z.
[4] Solano, E.; Dendooven, J.; Deduytsche, D.; Poonkottil, N.; Feng, J. Y.; Roeffaers, M. B. J.; Detavernier, C.; Filez, M. Metal Nanocatalyst Sintering Interrogated at Complementary Length Scales. Small 2023, 19 (5). DOI: 10.1002/smll.202205217.

Keywords

atomic layer deposition | in situ | nanostructure

Symposium Organizers

Jolien Dendooven, Ghent University
Masaru Hori, Nagoya University
David Munoz-Rojas, LMGP Grenoble INP/CNRS
Christophe Vallee, University at Albany, State University of New York

Session Chairs

Agnes Granier
Tsutsumi Takayoshi

In this Session