Experimental setup forin situX-ray SAXS/WAXS/PDF studies of the formation and growth of nanoparticles in near- and supercritical fluids

2010 ◽  
Vol 43 (4) ◽  
pp. 729-736 ◽  
Author(s):  
Jacob Becker ◽  
Martin Bremholm ◽  
Christoffer Tyrsted ◽  
Brian Pauw ◽  
Kirsten Marie Ø. Jensen ◽  
...  

The growing interest in inorganic nanoparticles for a wide range of applications is spurring a need for synthesis methods that allow a highly specific tailoring of material properties. Synthesis in supercritical fluids holds great promise for solving this problem, but so far the fundamental chemical processes taking place under these conditions are to a large extent unknown. Here the design, construction and application of a versatile experimental setup are reported; this setup enablesin situsynchrotron small-angle X-ray scattering/wide-angle X-ray scattering/pair distribution function (SAXS/WAXS/PDF) studies of the formation and growth of nanoparticles under supercritical fluid conditions.

2012 ◽  
Vol 18 (18) ◽  
pp. 5759-5766 ◽  
Author(s):  
Christoffer Tyrsted ◽  
Brian Richard Pauw ◽  
Kirsten Marie Ørnsbjerg Jensen ◽  
Jacob Becker ◽  
Mogens Christensen ◽  
...  

2014 ◽  
Vol 70 (a1) ◽  
pp. C1069-C1069
Author(s):  
Bo Iversen

Reactions in steel containers under solvo/hydrothermal conditions are widely used to produce crystalline nanoparticles. The solvo/hydrothermal approach often provides excellent control over nanoparticle characteristics such as size, size distribution, morphology and crystallinity. However, most progress in the solvothermal field is empirical in nature. Recent development of in situ X-ray scattering techniques now allow real time monitoring of the formation of nanoparticles under high pressure, high temperature conditions, and this opens up the possibility for synthesizing nanoparticles by design. We have developed unique in situ reactors for studies of reactions in sub- and supercritical fluids [1]. By means of Small Angle X-ray Scattering (SAXS), Wide Angle X-ray Scattering (WAXS), Total scattering and EXAFS we have obtained knowledge on the formation and growth of a range of important nanoparticles all the way from the precursor structures to the final crystalline product. In the talk recent examples will be discussed. [1] (a) Jensen et al., Angew. Chem. 2007, 46, 1113; (b) Bremholm et al., Angew Chem. 2009, 48, 4788; (c) Bremholm et al., Adv. Mater. 2009, 21, 3572; (d) Lock et al, Angew Chem. 2011, 50, 7045; (e) Jensen et al., J. Am. Chem. Soc. 2012, 134, 6785; (f) Tyrsted et al, Angew. Chem. 2012, 51, 9030; (g) Nørby et al., RSC Adv. 2013, 3, 15368; (h) Eltzholtz et al., Nanoscale 2013, 5, 2372


2019 ◽  
Author(s):  
Christian Prehal ◽  
Aleksej Samojlov ◽  
Manfred Nachtnebel ◽  
Manfred Kriechbaum ◽  
Heinz Amenitsch ◽  
...  

<b>Here we use in situ small and wide angle X-ray scattering to elucidate unexpected mechanistic insights of the O2 reduction mechanism in Li-O2 batteries.<br></b>


2019 ◽  
Author(s):  
Hao Wu ◽  
Jeffrey Ting ◽  
Siqi Meng ◽  
Matthew Tirrell

We have directly observed the <i>in situ</i> self-assembly kinetics of polyelectrolyte complex (PEC) micelles by synchrotron time-resolved small-angle X-ray scattering, equipped with a stopped-flow device that provides millisecond temporal resolution. This work has elucidated one general kinetic pathway for the process of PEC micelle formation, which provides useful physical insights for increasing our fundamental understanding of complexation and self-assembly dynamics driven by electrostatic interactions that occur on ultrafast timescales.


Author(s):  
Ilya V. Roslyakov ◽  
Andrei P. Chumakov ◽  
Andrei A. Eliseev ◽  
Alexey P. Leontiev ◽  
Oleg V. Konovalov ◽  
...  

Catalysts ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 730
Author(s):  
Erik Sarnello ◽  
Tao Li

Enzyme immobilization techniques are widely researched due to their wide range of applications. Polymer–protein core–shell nanoparticles (CSNPs) have emerged as a promising technique for enzyme/protein immobilization via a self-assembly process. Based on the desired application, different sizes and distribution of the polymer–protein CSNPs may be required. This work systematically studies the assembly process of poly(4-vinyl pyridine) and bovine serum albumin CSNPs. Average particle size was controlled by varying the concentrations of each reagent. Particle size and size distributions were monitored by dynamic light scattering, ultra-small-angle X-ray scattering, small-angle X-ray scattering and transmission electron microscopy. Results showed a wide range of CSNPs could be assembled ranging from an average radius as small as 52.3 nm, to particles above 1 µm by adjusting reagent concentrations. In situ X-ray scattering techniques monitored particle assembly as a function of time showing the initial particle growth followed by a decrease in particle size as they reach equilibrium. The results outline a general strategy that can be applied to other CSNP systems to better control particle size and distribution for various applications.


Polymers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1764
Author(s):  
Lison Rocher ◽  
Andrew S. Ylitalo ◽  
Tiziana Di Luccio ◽  
Riccardo Miscioscia ◽  
Giovanni De Filippo ◽  
...  

In situ synchrotron X-ray scattering was used to reveal the transient microstructure of poly(L-lactide) (PLLA)/tungsten disulfide inorganic nanotubes (WS2NTs) nanocomposites. This microstructure is formed during the blow molding process (“tube expansion”) of an extruded polymer tube, an important step in the manufacturing of PLLA-based bioresorbable vascular scaffolds (BVS). A fundamental understanding of how such a microstructure develops during processing is relevant to two unmet needs in PLLA-based BVS: increasing strength to enable thinner devices and improving radiopacity to enable imaging during implantation. Here, we focus on how the flow generated during tube expansion affects the orientation of the WS2NTs and the formation of polymer crystals by comparing neat PLLA and nanocomposite tubes under different expansion conditions. Surprisingly, the WS2NTs remain oriented along the extrusion direction despite significant strain in the transverse direction while the PLLA crystals (c-axis) form along the circumferential direction of the tube. Although WS2NTs promote the nucleation of PLLA crystals in nanocomposite tubes, crystallization proceeds with largely the same orientation as in neat PLLA tubes. We suggest that the reason for the unusual independence of the orientations of the nanotubes and polymer crystals stems from the favorable interaction between PLLA and WS2NTs. This favorable interaction leads WS2NTs to disperse well in PLLA and strongly orient along the axis of the PLLA tube during extrusion. As a consequence, the nanotubes are aligned orthogonally to the circumferential stretching direction, which appears to decouple the orientations of PLLA crystals and WS2NTs.


2019 ◽  
Vol 92 ◽  
pp. 01005
Author(s):  
Georgios Birmpilis ◽  
Reza Ahmadi-Naghadeh ◽  
Jelke Dijkstra

X-ray scattering is a promising non-invasive technique to study evolving nano- and micromechanics in clays. This study discusses the experimental considerations and a successful method to enable X-ray scattering to study clay samples at two extreme stages of consolidation. It is shown that the proposed sample environment comprising flat capillaries with a hydrophobic coating can be used for a wide range of voids ratios ranging from a clay suspension to consolidated clay samples, that are cut from larger specimens of reconstituted or natural clay. The initial X-ray scattering results using a laboratory instrument indicate that valuable information on, in principal evolving, clay fabric can be measured. Features such as characteristic distance between structural units and particle orientations are obtained for a slurry and a consolidated sample of kaolinite. Combined with other promising measurement techniques from Materials Science the proposed method will help advance the contemporary understanding on the behaviour of dense colloidal systems of clay, as it does not require detrimental sample preparation


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