Monitoring Catalytic 2-Propanol Oxidation over Co3O4 Nanowires via In Situ Photoluminescence Spectroscopy

Spectroscopic methods enabling real-time monitoring of dynamic surface processes are a prerequisite for identifying how a catalyst triggers a chemical reaction. We present an in situ photoluminescence spectroscopy approach for probing the thermo-catalytic 2-propanol oxidation over mesostructured Co3O4 nanowires. Under oxidative conditions, a distinct blue emission at ~420 nm is detected that increases with temperature up to 280 °C, with an intermediate maximum at 150 °C. Catalytic data gained under comparable conditions show that this course of photoluminescence intensity precisely follows the conversion of 2-propanol and the production of acetone. The blue emission is assigned to the radiative recombination of unbound acetone molecules, the n - π* transition of which is selectively excited by a wavelength of 270 nm. These findings open a pathway for studying thermo-catalytic processes via in situ photoluminescence spectroscopy thereby gaining information about the performance of the catalyst and the formation of intermediate products.

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Chemical Reaction at Specific Sites and Reaction-Induced Self-Assembly as Observed by in Situ and Real Time SANS: Enzymatic Polymerization to Synthetic Cellulose

Biomacromolecules ◽

10.1021/bm0605255 ◽

2006 ◽

Vol 7 (9) ◽

pp. 2479-2482 ◽

Cited By ~ 10

Author(s):

Takeji Hashimoto ◽

Hirokazu Tanaka ◽

Satoshi Koizumi ◽

Kazuhiro Kurosaki ◽

Masashi Ohmae ◽

...

Keyword(s):

Real Time ◽

Chemical Reaction ◽

Self Assembly ◽

Enzymatic Polymerization

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In Situ Real-time Environmental High Resolution Electron Microscopy of Nanometer Size Novel Xerogel Catalysts for Hydrogenation Reactions in Nylon 6,6

Microscopy and Microanalysis ◽

10.1017/s1431927602000582 ◽

2000 ◽

Vol 6 (4) ◽

pp. 335-342 ◽

Cited By ~ 16

Author(s):

Pratibha L. Gai ◽

Kostantinos Kourtakis ◽

Stanislav Ziemecki

Keyword(s):

Electron Microscopy ◽

High Resolution ◽

Real Time ◽

High Resolution Electron Microscopy ◽

Dynamic Surface ◽

Nanometer Size ◽

Heterogeneous Catalytic ◽

Resolution Electron ◽

Nylon 6,6

AbstractIn situ real-time environmental high resolution electron microscopy (EHREM) under controlled reaction environments permits direct atomic resolution imaging of dynamic surface and sub-surface microstructures of reacting catalysts. Using the EHREM and complementary microscopy methods, we have investigated selective hydrogenation reaction mechanisms over novel xerogel catalysts of ruthenium and Ru with Co and Au promoters on titania supports, and report an alternative heterogeneous catalytic process for the hydrogenation of adiponitrile (ADN) in the manufacture of Nylon 6,6. The direct EHREM observations are supported by ultra-high resolution low voltage scanning electron microscope (SEM) of spatial distributions of the highly dispersed nanometer-size catalyst particles and parallel chemical studies. The results demonstrate the important role of in situ EHREM in the design of heterogeneous catalytic hydrogenation processes on the nanoscale.

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ION SCATTERING AND RECOILING SPECTROSCOPY FOR REAL TIME MONITORING OF SURFACE PROCESSES IN A GAS PHASE ATMOSPHERE

Surface Review and Letters ◽

10.1142/s0218625x00000725 ◽

2000 ◽

Vol 07 (05n06) ◽

pp. 657-659

Author(s):

T. FUJINO ◽

M. KATAYAMA ◽

Y. YAMAZAKI ◽

S. INOUE ◽

J.-T. RYU ◽

...

Keyword(s):

Real Time ◽

Film Growth ◽

Hydrogen Gas ◽

Surface Processes ◽

Ion Scattering ◽

Real Time Monitoring ◽

Si Substrates ◽

Pumping System ◽

Differential Pumping

Various surface processes, such as thin film growth or etching, are usually performed by introducing various gases into a vacuum chamber. In order to monitor such surface processes in situ, we have developed an ion scattering and recoiling spectroscopy apparatus equipped with a differential pumping system. The system was applied for real time monitoring of hydrogen-mediated growth of Ge films on Si substrates under a hydrogen gas pressure of 10-4 Torr.

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Single-Shot Multicontrast X-ray Imaging for In Situ Visualization of Chemical Reaction Products

Journal of Imaging ◽

10.3390/jimaging7110221 ◽

2021 ◽

Vol 7 (11) ◽

pp. 221

Author(s):

Margarita Zakharova ◽

Andrey Mikhaylov ◽

Vitor Vlnieska ◽

Danays Kunka

Keyword(s):

Real Time ◽

Chemical Reaction ◽

Single Shot ◽

Reaction Products ◽

Time Resolved ◽

X Ray ◽

X Ray Imaging ◽

In Situ Visualization ◽

Different Time Scales

We present the application of single-shot multicontrast X-ray imaging with an inverted Hartmann mask to the time-resolved in situ visualization of chemical reaction products. The real-time monitoring of an illustrative chemical reaction indicated the formation of the precipitate by the absorption, differential phase, and scattering contrast images obtained from a single projection. Through these contrast channels, the formation of the precipitate along the mixing line of the reagents, the border between the solid and the solution, and the presence of the scattering structures of 100–200 nm sizes were observed. The measurements were performed in a flexible and robust setup, which can be tailored to various imaging applications at different time scales.

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Dynamic surface properties of PEG-coated CuS nanoparticles alter their interaction with cells as revealed by surface-enhanced infrared spectroscopy

Nanoscale Advances ◽

10.1039/c9na00371a ◽

2019 ◽

Vol 1 (11) ◽

pp. 4268-4276

Author(s):

Fengjuan Cao ◽

Lie Wu ◽

Xiaofei Zhang ◽

Shanshan Li ◽

Chao Wang ◽

...

Keyword(s):

Infrared Spectroscopy ◽

Real Time ◽

Surface Properties ◽

Cell Interaction ◽

Label Free ◽

Dynamic Changes ◽

Dynamic Surface ◽

Surface Enhanced ◽

First Time

How the dynamic changes of the surface properties of nanoparticles affect the nano-cell interaction was revealed for the first time, by in situ real-time label-free SEIRA spectroscopy at the nanoscale.

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In Situ Real-time Environmental High Resolution Electron Microscopy of Nanometer Size Novel Xerogel Catalysts for Hydrogenation Reactions in Nylon 6,6

Microscopy and Microanalysis ◽

10.1007/s100050010038 ◽

2000 ◽

Vol 6 (4) ◽

pp. 335-342 ◽

Cited By ~ 1

Author(s):

Pratibha L. Gai ◽

Kostantinos Kourtakis ◽

Stanislav Ziemecki

Keyword(s):

Electron Microscopy ◽

High Resolution ◽

Real Time ◽

High Resolution Electron Microscopy ◽

Dynamic Surface ◽

Nanometer Size ◽

Heterogeneous Catalytic ◽

Resolution Electron ◽

Nylon 6,6

Abstract In situ real-time environmental high resolution electron microscopy (EHREM) under controlled reaction environments permits direct atomic resolution imaging of dynamic surface and sub-surface microstructures of reacting catalysts. Using the EHREM and complementary microscopy methods, we have investigated selective hydrogenation reaction mechanisms over novel xerogel catalysts of ruthenium and Ru with Co and Au promoters on titania supports, and report an alternative heterogeneous catalytic process for the hydrogenation of adiponitrile (ADN) in the manufacture of Nylon 6,6. The direct EHREM observations are supported by ultra-high resolution low voltage scanning electron microscope (SEM) of spatial distributions of the highly dispersed nanometer-size catalyst particles and parallel chemical studies. The results demonstrate the important role of in situ EHREM in the design of heterogeneous catalytic hydrogenation processes on the nanoscale.

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In situ microspectroscopic monitoring within a microfluidic reactor

RSC Advances ◽

10.1039/c4ra01650e ◽

2014 ◽

Vol 4 (28) ◽

pp. 14569-14572 ◽

Cited By ~ 6

Author(s):

Robert Zmijan ◽

Michele Carboni ◽

Lorenzo Capretto ◽

Eugen Stulz ◽

Xunli Zhang

Keyword(s):

Real Time ◽

Monitoring System ◽

Chemical Reaction ◽

Formation Process ◽

Reaction Progress ◽

Silver Nanoprisms ◽

Microfluidic Reactor ◽

Rapid Changes ◽

Short Section

A novel in situ microspectroscopic monitoring system has been developed for real time monitoring of chemical reaction progress within a microfluidic reactor by absorbance measurements. The formation process and rapid changes in size and shape of silver nanoprisms were successfully detected and reveal that these changes take place in a very short section of the microreactor.

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Probing the Dynamic Self-Assembly Behaviour of Photoswitchable Wormlike Micelles in Real Time

10.26434/chemrxiv.7098695 ◽

2018 ◽

Author(s):

Elaine A. Kelly ◽

Judith E. Houston ◽

Rachel Evans

Keyword(s):

Real Time ◽

Absorption Spectroscopy ◽

Self Assembly ◽

Uv Light ◽

Wormlike Micelles ◽

Tetraethylene Glycol ◽

Light Illumination ◽

First Time ◽

Dependent Processes

Understanding the dynamic self-assembly behaviour of azobenzene photosurfactants (AzoPS) is crucial to advance their use in controlled release applications such asdrug delivery and micellar catalysis. Currently, their behaviour in the equilibrium cis-and trans-photostationary states is more widely understood than during the photoisomerisation process itself. Here, we investigate the time-dependent self-assembly of the different photoisomers of a model neutral AzoPS, <a>tetraethylene glycol mono(4′,4-octyloxy,octyl-azobenzene) </a>(C8AzoOC8E4) using small-angle neutron scattering (SANS). We show that the incorporation of in-situUV-Vis absorption spectroscopy with SANS allows the scattering profile, and hence micelle shape, to be correlated with the extent of photoisomerisation in real-time. It was observed that C8AzoOC8E4could switch between wormlike micelles (transnative state) and fractal aggregates (under UV light), with changes in the self-assembled structure arising concurrently with changes in the absorption spectrum. Wormlike micelles could be recovered within 60 seconds of blue light illumination. To the best of our knowledge, this is the first time the degree of AzoPS photoisomerisation has been tracked in-situthrough combined UV-Vis absorption spectroscopy-SANS measurements. This technique could be widely used to gain mechanistic and kinetic insights into light-dependent processes that are reliant on self-assembly.

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