Reactor for nano-focused x-ray diffraction and imaging under catalytic <i>in situ</i> conditions

Richard, Marie-Ingrid; Fernandez, Sylvie; Hofmann, Jan P.; Gao, Lu; Chahine, Gilbert; Leake, Steven; Djazouli, Hamid; Bortoli, Y. De; Petit, L.; Boesecke, Peter; Labat, S.; Hensen, Emiel J. M.; Thomas, O.; Schülli, Tobias U.

doi:10.1063/1.5000015

Cited by 7 publications

(3 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This resulted in a footprint of 520 nm along the beam for the employed incident angle of 18.75°. The diffraction patterns were recorded by a 2D MAXIPIX detector with 55 μm pixel size installed at a sample-to-detector distance of 0.68 m. The sample was mounted in a small flow cell equipped with a Be dome and a sample heater . Pure Ar and Ar/CO mixtures were introduced by a computer controlled gas cabinet at a constant total flow of 20 mL/min and a total pressure of 50 mbar (see section 3 of the Supporting Information).…”

Section: Experimental Sectionmentioning

confidence: 99%

Coherent X-ray Imaging of CO-Adsorption-Induced Structural Changes in Pt Nanoparticles: Implications for Catalysis

Abuín

Kim

Runge

et al. 2019

ACS Appl. Nano Mater.

View full text Add to dashboard Cite

Using coherent X-ray diffraction imaging (CXDI) as an in situ tool, we determined the shape and strain state of a platinum nanoparticle with ≈160 nm diameter supported by a strontium titanate substrate. The experiment was performed at a temperature of 400 K under continuous gas flow conditions of pure Ar and Ar/CO mixtures. The nanoparticle was preselected by scanning electron microscopy (SEM) and postanalyzed by atomic force microscopy (AFM). We obtain a very good agreement between the overall nanoparticle size, shape, and defect structure as determined by CXDI and AFM. In addition, we compare the strain state in the nanoparticle near surface region and its bulk: For pure Ar flow, we find a slight compressive strain in the nanoparticle bulk compared to an expansion in the near surface region. We ascribe the latter to the presence of high index vicinal surfaces. Our analysis suggests that under mixed Ar/CO flow at 400 K reshaping of the nanoparticle occurred. New high index facets developed, leading to a stronger lattice expansion, also propagating into the nanoparticle bulk. Our high-resolution experiments pave the way for future CXDI experiments under operando catalytic reaction conditions.

show abstract

Section: Experimental Sectionmentioning

confidence: 99%

Coherent X-ray Imaging of CO-Adsorption-Induced Structural Changes in Pt Nanoparticles: Implications for Catalysis

Abuín

Kim

Runge

et al. 2019

ACS Appl. Nano Mater.

View full text Add to dashboard Cite

show abstract

“…In particular, systems combining low or high temperatures with high electric fields and low sample-stage-induced current background in vacuum are not available. However, customized chambers for nearly every purpose can be designed individually (Richard et al, 2017). The electrical and simultaneous structural investigation represents the major application of this chamber.…”

Section: Introductionmentioning

confidence: 99%

Sample chamber for synchrotron based in-situ X-ray diffraction experiments under electric fields and temperatures between 100 K and 1250 K

Nentwich¹,

Weigel²,

Richter³

et al. 2021

J Synchrotron Radiat

View full text Add to dashboard Cite

Many scientific questions require X-ray experiments conducted at varying temperatures, sometimes combined with the application of electric fields. Here, a customized sample chamber developed for beamlines P23 and P24 of PETRA III at DESY to suit these demands is presented. The chamber body consists mainly of standard vacuum parts housing the heater/cooler assembly supplying a temperature range of 100 K to 1250 K and an xyz manipulator holding an electric contact needle for electric measurements at both high voltage and low current. The chamber is closed by an exchangeable hemispherical dome offering all degrees of freedom for single-crystal experiments within one hemisphere of solid angle. The currently available dome materials (PC, PS, PEEK polymers) differ in their absorption and scattering characteristics, with PEEK providing the best overall performance. The article further describes heating and cooling capabilities, electric characteristics, and plans for future upgrades of the chamber. Examples of applications are discussed.

show abstract

“…With the increased coherent flux provided by modern sources, BCDI has great potential for the study of smaller particles. In the case of catalytic or electrochemical reactions (Richard et al, 2017;Rochet et al, 2019;Bjö rling et al, 2019), particle sizes in the 1-10 nm range useful for industrially relevant reactions (Campbell et al, 2016) can be studied. The relative intensity between the Bragg peaks and the secondary maxima depends on the particle size; thus, the relative effect of Compton scattering will be more important for small particles.…”

Section: Introductionmentioning

confidence: 99%

On Compton scattering as a source of background in coherent diffraction imaging experiments

Bikondoa¹,

Carbone²

2021

J Synchrotron Radiat

View full text Add to dashboard Cite

Compton scattering is generally neglected in diffraction experiments because the incoherent radiation it generates does not give rise to interference effects and therefore is negligible at Bragg peaks. However, as the scattering volume is reduced, the difference between the Rayleigh (coherent) and Compton (incoherent) contributions at Bragg peaks diminishes and the incoherent part may become substantial. The consequences can be significant for coherent diffraction imaging at high scattering angles: the incoherent radiation produces background that smears out the secondary interference fringes, affecting thus the achievable resolution of the technique. Here, a criterion that relates the object shape and the resolution is introduced. The Compton contribution for several object shapes is quantified, and it is shown that the maximum achievable resolution along different directions has a strong dependence on the crystal shape and size.

show abstract

Reactor for nano-focused x-ray diffraction and imaging under catalytic in situ conditions

Cited by 7 publications

References 22 publications

Coherent X-ray Imaging of CO-Adsorption-Induced Structural Changes in Pt Nanoparticles: Implications for Catalysis

Coherent X-ray Imaging of CO-Adsorption-Induced Structural Changes in Pt Nanoparticles: Implications for Catalysis

Sample chamber for synchrotron based in-situ X-ray diffraction experiments under electric fields and temperatures between 100 K and 1250 K

On Compton scattering as a source of background in coherent diffraction imaging experiments

Contact Info

Product

Resources

About