In situsimultaneous Raman/high-resolution X-ray powder diffraction study of transformations occurring in materials at non-ambient conditions

Abstract

Materials containing disordered moieties and/or amorphous or liquid-like phases or showing surface-or defect-related phenomena constitute a problem with respect to their characterization using X-ray powder diffraction (XRPD), and in many cases Raman spectroscopy can provide useful complementary information. A novel experimental setup has been designed and realized for simultaneous in situ Raman/high-resolution XRPD experiments, to take full advantage of the complementarities of the two techniques in investigating solidstate transformations under non-ambient conditions. The added value of the proposed experiment is the perfect synchronization of the two probes with the reaction coordinate and the elimination of possible bias caused by different sample holders and conditioning modes used in 'in situ but separate' approaches. The setup was tested on three solid-state transformations: (i) the kinetics of the fluorene-TCNQ solid-state synthesis, (ii) the thermal swelling and degradation of stearate-hydrotalcite, and (iii) the photoinduced (2 + 2)-cyclization of (E)furylidenoxindole. These experiments demonstrated that, even though the simultaneous Raman/XRPD experiment is more challenging than separate procedures, high-resolution XRPD and Raman data can be collected. A gas blower allows studies from room temperature to 700 K, and 100 K can be reached using a nitrogen cryostream. The flexibility of the experimental setup allows the addition of ancillary devices, such as a UV lamp used to study photoreactivity. research papers J. Appl. Cryst. (2007). 40, 684-693 Enrico Boccaleri et al. Transformations at non-ambient conditions 685 research papers 686 Enrico Boccaleri et al. Transformations at non-ambient conditions

A combined synchrotron powder diffraction and vibrational study of the thermal treatment of palygorskite–indigo to produce Maya blue

“…The large increase in intensity of the 110 peak upon dehydration is due to the enhancement of the electron density contrast as the tUlmels become empty [33]. In fact, if one supposes that water is lost at approximately the same rate from the two zeolitic sites, as suggested in Ref.…”

“…The temperature ramp was set to 1°C/min. More details and the Raman/XRD experimental setup and on the data collection strategy are reported elsewhere [33].…”

“…11id-infrared (MlR) and near-infrared (NIR) spectroscopies as well as porosity measurements are employed to study the rehy dration of MB. Beyond the specifics of the indigo-paly gorskite interaction, this study belongs to a broader effort in understanding the formation and properties of hybrid organic-inorganic materials involving layered structures [33].…”

Applying Dynamic and Synchronous DRIFTS/EXAFS to the Structural Reactive Behaviour of Dilute (≤1 wt%) Supported Rh/Al2O3 Catalysts using Quick and Energy Dispersive EXAFS

“…Synchronously applied combinations of structurally direct X-ray based techniques, such as EXAFS, XRD, and SAXS/WAXS, together with vibrational spectroscopies (such as Raman [2][3][4][5] and infrared spectroscopies [6][7][8][9][10][11][12]), and techniques that give a global overview of catalytic performance (such as mass spectrometry and gas chromatography), are particularly attractive. A number of these types of experiments [2][3][4][5][6][7][8][9][10][11][12] have now been demonstrated, and it seems certain that they will become ever more powerful as the process of refining them, and developing M. A. Newton (&) The European Synchrotron Radiation Facility, 6 Rue Jules Horowitz, BP-220, Grenoble 38043, France e-mail: newton@esrf.fr new ones, continues in response to the ever increasing desires of the catalysis, chemistry, and wider material science communities.…”

A flexible gas flow reaction cell for in situ x-ray absorption spectroscopy studies

“…the structure of the catalysts can be determined simultaneously with the measurement of the catalytic performance using mass spectrometry (MS). Other techniques that can be combined with the XAS are XRD 1, 2 , UV-visible and Raman spectroscopy 3, , XRD with Raman spectroscopy 4 , Raman/UV-visible combined with Small Angle X-ray Scattering (SAXS) and Wide Angle X-ray Scattering (WAXS) developed by Beale 5 , Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS) and Mass Spectroscopy (MS) 6 .…”