Mapping the Pore Architecture of Structured Catalyst Monoliths from Nanometer to Centimeter Scale with Electron and X-ray Tomographies

Johannes Becher, Thomas L. Sheppard*, Yakub Fam, Sina Baier, Wu Wang, Di Wang, Satishkumar Kulkarni, Thomas F. Keller, Mikhail Lyubomirskiy, Dennis Brueckner, Maik Kahnt, Andreas Schropp, Christian G. Schroer, Jan-Dierk Grunwaldt

*Corresponding author for this work

Research output: Contribution to journalJournal articleResearchpeer-review

Abstract

The hierarchicalpore systems of Pt/Al2O3 exhaust gas aftertreatment catalysts were analyzed with a collection of correlative imaging techniques to monitor changes induced by hydrothermal aging. Synergistic imaging with laboratory X-ray microtomography, synchrotron radiation ptychographic X-ray computed nanotomography, and electron tomography allowed quantitative observation of the catalyst pore architecture from centimeter to nanometer scale. Thermal aging at 750 °C in air and hydrothermal aging at 1050 °C in 10% H2O/air caused increasing structural degradation, which manifested as widespread sintering of Pt particles, increased volumeand quantity of macropores (>20 nm), and reduction in effectivesurfacearea coupled with decreasing volume and frequency of mesopores (2–20nm) and micropores (<2 nm). Electron tomography unraveled the three-dimensional (3D) structure with high resolution allowing visualization of meso- and macropores but with samples of maximum 300 nm thickness. To complement this, hard X-ray ptychographic tomography produced quantitative 3D electron density maps of 5 μm diameter samples with spatial resolution <50 nm, effectively filling the resolution gap between electron tomography and hard X-ray microtomography. The obtained 3D volumes are an essential input for future computational modeling of fluid dynamics, mass transport, or diffusion properties and may readily complement bulk onedimensional porosimetry measurements or simulated porosity.
Original languageEnglish
JournalJournal of Physical Chemistry C
Volume123
Issue number41
Pages (from-to)25197-25208
Number of pages12
ISSN1932-7447
DOIs
Publication statusPublished - 2019

Cite this

Becher, Johannes ; Sheppard, Thomas L. ; Fam, Yakub ; Baier, Sina ; Wang, Wu ; Wang, Di ; Kulkarni, Satishkumar ; Keller, Thomas F. ; Lyubomirskiy, Mikhail ; Brueckner, Dennis ; Kahnt, Maik ; Schropp, Andreas ; Schroer, Christian G. ; Grunwaldt, Jan-Dierk. / Mapping the Pore Architecture of Structured Catalyst Monoliths from Nanometer to Centimeter Scale with Electron and X-ray Tomographies. In: Journal of Physical Chemistry C. 2019 ; Vol. 123, No. 41. pp. 25197-25208.
@article{f9557df316184f4cb4fa386ef5562a45,
title = "Mapping the Pore Architecture of Structured Catalyst Monoliths from Nanometer to Centimeter Scale with Electron and X-ray Tomographies",
abstract = "The hierarchicalpore systems of Pt/Al2O3 exhaust gas aftertreatment catalysts were analyzed with a collection of correlative imaging techniques to monitor changes induced by hydrothermal aging. Synergistic imaging with laboratory X-ray microtomography, synchrotron radiation ptychographic X-ray computed nanotomography, and electron tomography allowed quantitative observation of the catalyst pore architecture from centimeter to nanometer scale. Thermal aging at 750 °C in air and hydrothermal aging at 1050 °C in 10{\%} H2O/air caused increasing structural degradation, which manifested as widespread sintering of Pt particles, increased volumeand quantity of macropores (>20 nm), and reduction in effectivesurfacearea coupled with decreasing volume and frequency of mesopores (2–20nm) and micropores (<2 nm). Electron tomography unraveled the three-dimensional (3D) structure with high resolution allowing visualization of meso- and macropores but with samples of maximum 300 nm thickness. To complement this, hard X-ray ptychographic tomography produced quantitative 3D electron density maps of 5 μm diameter samples with spatial resolution <50 nm, effectively filling the resolution gap between electron tomography and hard X-ray microtomography. The obtained 3D volumes are an essential input for future computational modeling of fluid dynamics, mass transport, or diffusion properties and may readily complement bulk onedimensional porosimetry measurements or simulated porosity.",
author = "Johannes Becher and Sheppard, {Thomas L.} and Yakub Fam and Sina Baier and Wu Wang and Di Wang and Satishkumar Kulkarni and Keller, {Thomas F.} and Mikhail Lyubomirskiy and Dennis Brueckner and Maik Kahnt and Andreas Schropp and Schroer, {Christian G.} and Jan-Dierk Grunwaldt",
year = "2019",
doi = "10.1021/acs.jpcc.9b06541",
language = "English",
volume = "123",
pages = "25197--25208",
journal = "The Journal of Physical Chemistry Part C",
issn = "1932-7447",
publisher = "American Chemical Society",
number = "41",

}

Becher, J, Sheppard, TL, Fam, Y, Baier, S, Wang, W, Wang, D, Kulkarni, S, Keller, TF, Lyubomirskiy, M, Brueckner, D, Kahnt, M, Schropp, A, Schroer, CG & Grunwaldt, J-D 2019, 'Mapping the Pore Architecture of Structured Catalyst Monoliths from Nanometer to Centimeter Scale with Electron and X-ray Tomographies', Journal of Physical Chemistry C, vol. 123, no. 41, pp. 25197-25208. https://doi.org/10.1021/acs.jpcc.9b06541

Mapping the Pore Architecture of Structured Catalyst Monoliths from Nanometer to Centimeter Scale with Electron and X-ray Tomographies. / Becher, Johannes; Sheppard, Thomas L.; Fam, Yakub; Baier, Sina; Wang, Wu; Wang, Di; Kulkarni, Satishkumar; Keller, Thomas F.; Lyubomirskiy, Mikhail; Brueckner, Dennis; Kahnt, Maik; Schropp, Andreas; Schroer, Christian G.; Grunwaldt, Jan-Dierk.

In: Journal of Physical Chemistry C, Vol. 123, No. 41, 2019, p. 25197-25208.

Research output: Contribution to journalJournal articleResearchpeer-review

TY - JOUR

T1 - Mapping the Pore Architecture of Structured Catalyst Monoliths from Nanometer to Centimeter Scale with Electron and X-ray Tomographies

AU - Becher, Johannes

AU - Sheppard, Thomas L.

AU - Fam, Yakub

AU - Baier, Sina

AU - Wang, Wu

AU - Wang, Di

AU - Kulkarni, Satishkumar

AU - Keller, Thomas F.

AU - Lyubomirskiy, Mikhail

AU - Brueckner, Dennis

AU - Kahnt, Maik

AU - Schropp, Andreas

AU - Schroer, Christian G.

AU - Grunwaldt, Jan-Dierk

PY - 2019

Y1 - 2019

N2 - The hierarchicalpore systems of Pt/Al2O3 exhaust gas aftertreatment catalysts were analyzed with a collection of correlative imaging techniques to monitor changes induced by hydrothermal aging. Synergistic imaging with laboratory X-ray microtomography, synchrotron radiation ptychographic X-ray computed nanotomography, and electron tomography allowed quantitative observation of the catalyst pore architecture from centimeter to nanometer scale. Thermal aging at 750 °C in air and hydrothermal aging at 1050 °C in 10% H2O/air caused increasing structural degradation, which manifested as widespread sintering of Pt particles, increased volumeand quantity of macropores (>20 nm), and reduction in effectivesurfacearea coupled with decreasing volume and frequency of mesopores (2–20nm) and micropores (<2 nm). Electron tomography unraveled the three-dimensional (3D) structure with high resolution allowing visualization of meso- and macropores but with samples of maximum 300 nm thickness. To complement this, hard X-ray ptychographic tomography produced quantitative 3D electron density maps of 5 μm diameter samples with spatial resolution <50 nm, effectively filling the resolution gap between electron tomography and hard X-ray microtomography. The obtained 3D volumes are an essential input for future computational modeling of fluid dynamics, mass transport, or diffusion properties and may readily complement bulk onedimensional porosimetry measurements or simulated porosity.

AB - The hierarchicalpore systems of Pt/Al2O3 exhaust gas aftertreatment catalysts were analyzed with a collection of correlative imaging techniques to monitor changes induced by hydrothermal aging. Synergistic imaging with laboratory X-ray microtomography, synchrotron radiation ptychographic X-ray computed nanotomography, and electron tomography allowed quantitative observation of the catalyst pore architecture from centimeter to nanometer scale. Thermal aging at 750 °C in air and hydrothermal aging at 1050 °C in 10% H2O/air caused increasing structural degradation, which manifested as widespread sintering of Pt particles, increased volumeand quantity of macropores (>20 nm), and reduction in effectivesurfacearea coupled with decreasing volume and frequency of mesopores (2–20nm) and micropores (<2 nm). Electron tomography unraveled the three-dimensional (3D) structure with high resolution allowing visualization of meso- and macropores but with samples of maximum 300 nm thickness. To complement this, hard X-ray ptychographic tomography produced quantitative 3D electron density maps of 5 μm diameter samples with spatial resolution <50 nm, effectively filling the resolution gap between electron tomography and hard X-ray microtomography. The obtained 3D volumes are an essential input for future computational modeling of fluid dynamics, mass transport, or diffusion properties and may readily complement bulk onedimensional porosimetry measurements or simulated porosity.

U2 - 10.1021/acs.jpcc.9b06541

DO - 10.1021/acs.jpcc.9b06541

M3 - Journal article

VL - 123

SP - 25197

EP - 25208

JO - The Journal of Physical Chemistry Part C

JF - The Journal of Physical Chemistry Part C

SN - 1932-7447

IS - 41

ER -