Hard X‐ray Nanotomography of Catalytic Solids at Work

Gonzalez-Jimenez, Ines D.; Cats, Korneel H.; Davidian, Thomas; Ruitenbeek, Matthijs; Meirer, Florian; Liu, Yijin; Nelson, Johanna; Andrews, Joy C.; Pianetta, P.; Groot, Frank M. F. de; Weckhuysen, Bert M.

doi:10.1002/anie.201204930

Cited by 98 publications

(64 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…X-ray absorption near edge structure (XANES) has provided a new insight into chemical environment of biominerals and mineralised tissues [25][26][27][28][29][30].While XAS studies provide a very high energy resolution, the spatial resolution is not adequate to resolve features below 15nm [31][32][33]. Although the average sized crystal platelets (100nm long, 50nm wide, 5nm thick [34,35]) could be examined, investigation of smaller (5-10nm) features such as intercrystal spaces, grain boundaries and protein-mineral interfaces is below the spatial resolution limit of XAS.…”

Section: Introductionmentioning

confidence: 99%

Probing carbonate in bone forming minerals on the nanometre scale

et al. 2015

View full text Add to dashboard Cite

To devise new strategies to treat bone disease in an ageing society, a more detailed characterisation of the process by which bone mineralises is needed. In vitro studies have suggested that carbonated mineral might be a precursor for deposition of bone apatite. Increased carbonate content in bone may also have significant implications in altering the mechanical properties, for example in diseased bone. However, information about the chemistry and coordination environment of bone mineral, and their spatial distribution within healthy and diseased tissues, is lacking. Spatially resolved analytical transmission electron microscopy is the only method available to probe this information at the length scale of the collagen fibrils in bone. In this study, scanning transmission electron microscopy combined with electron energy-loss spectroscopy (STEM-EELS) was used to differentiate between calcium-containing biominerals (hydroxyapatite, carbonated hydroxyapatite, beta-tricalcium phosphate and calcite). A carbon K-edge peak at 290 eV is a direct marker of the presence of carbonate. We found that the oxygen K-edge structure changed most significantly between minerals allowing discrimination between calcium phosphates and calcium carbonates. The presence of carbonate in carbonated HA (CHA) was confirmed by the formation of peak at 533 eV in the oxygen K-edge. These observations were confirmed by simulations using density functional theory. Finally, we show that this method can be utilised to map carbonate from the crystallites in bone. We propose that our calibration library of EELS spectra could be extended to provide spatially resolved information about the coordination environment within bioceramic implants to stimulate the development of structural biomaterials.

show abstract

Section: Introductionmentioning

confidence: 99%

Probing carbonate in bone forming minerals on the nanometre scale

et al. 2015

View full text Add to dashboard Cite

show abstract

“…46 The latter report showed that hard X-ray TXM is particularly suited to the study of hierarchical structures in functional materials such as battery electrodes due to the strong X-ray penetration and depth of focus, enabling the study of large areas in 2D and 3D. 47–49 …”

Section: Introductionmentioning

confidence: 99%

Mesoscale Phase Distribution in Single Particles of LiFePO₄ following Lithium Deintercalation

et al. 2013

Self Cite

View full text Add to dashboard Cite

The chemical phase distribution in hydrothermally grown micrometric single crystals LiFePO4 following partial chemical delithiation was investigated. Full field and scanning X-ray microscopy were combined with X-ray absorption spectroscopy at the Fe K- and O K-edges, respectively, to produce maps with high chemical and spatial resolution. The resulting information was compared to morphological insight into the mechanics of the transformation by scanning transmission electron microscopy. This study revealed the interplay at the mesocale between microstructure and phase distribution during the redox process, as morphological defects were found to kinetically determine the progress of the reaction. Lithium deintercalation was also found to induce severe mechanical damage in the crystals, presumably due to the lattice mismatch between LiFePO4 and FePO4. Our results lead to the conclusion that rational design of intercalation-based electrode materials, such as LiFePO4, with optimized utilization and life requires the tailoring of particles that minimize kinetic barriers and mechanical strain. Coupling TXM-XANES with TEM can provide unique insight into the behavior of electrode materials during operation, at scales spanning from nanoparticles to ensembles and complex architectures.

show abstract

“…HP-XPS (highpressure X-ray spectroscopy), EXAFS (extended X-ray absorption fine structure) and NEXAFS (near edge X-ray absorption fine structures) spectroscopy measurements detect the oxidation state, coordination number, and composition of catalysts [45,46]. High spatial resolution XRD (X-ray diffraction) and EXAFS microspectroscopy along with X-ray tomography measurements tracked the dynamic changes in the structure and composition of catalysts [47][48][49][50]. These in situ measurements demonstrated that the catalytic surface is dynamic and its structure, composition, and electronic properties can be widely modified under reaction conditions.…”

Section: Advanced Instrumentation For In Situ Characterization Of Catmentioning

confidence: 99%

Molecular catalysis science: Nanoparticle synthesis and instrument development for studies under reaction conditions

Gross

Somorjai

2015

Journal of Catalysis

View full text Add to dashboard Cite

a b s t r a c tThe synthesis of architecturally designed catalytic nanostructures and their in situ characterization under reaction conditions enable the development of catalysts with improved stability, reactivity, and product selectivity. Throughout this review paper, we will explore three recent reports that demonstrate the invaluable synergetic impact of combining synthesis, catalysis, and in situ spectroscopy for catalysts development. In the first example, product selectivity in 1,3 butadiene hydrogenation reaction was tuned by employing size-selected Pt nanoparticles as catalysts. SFG vibrational spectroscopy measurements uncovered the mechanism that induced the size-dependent selectivity. The important role of metal/ metal-oxide interface during CO oxidation reaction is demonstrated in the second part of this review paper. In situ synchrotron-sourced X-ray spectroscopy correlated between the oxidation state of the metal-oxide support and its impact on the catalytic reactivity of supported Pt nanoparticles. In the third example, dendrimer-encapsulated Au nanoparticles were used as catalyst for cascade reactions, which were previously catalyzed by homogeneous catalysts. Reactants into product evolution and the oxidation state of catalytically active Au nanoparticles within the flow reactor were mapped with micrometer-sized IR and X-ray beams. These three examples demonstrate the important role of colloidal synthesis and in situ spectroscopy measurements for in-depth analysis of structure-reactivity correlations.

show abstract

Hard X‐ray Nanotomography of Catalytic Solids at Work

Cited by 98 publications

References 31 publications

Probing carbonate in bone forming minerals on the nanometre scale

Probing carbonate in bone forming minerals on the nanometre scale

Mesoscale Phase Distribution in Single Particles of LiFePO₄ following Lithium Deintercalation

Molecular catalysis science: Nanoparticle synthesis and instrument development for studies under reaction conditions

Contact Info

Product

Resources

About

Hard X‐ray Nanotomography of Catalytic Solids at Work

Cited by 98 publications

References 31 publications

Probing carbonate in bone forming minerals on the nanometre scale

Probing carbonate in bone forming minerals on the nanometre scale

Mesoscale Phase Distribution in Single Particles of LiFePO4 following Lithium Deintercalation

Molecular catalysis science: Nanoparticle synthesis and instrument development for studies under reaction conditions

Contact Info

Product

Resources

About

Mesoscale Phase Distribution in Single Particles of LiFePO₄ following Lithium Deintercalation