The new materials processing beamline at the SRS Daresbury, MPW6.2

Abstract

A new beamline (MPW6.2) has been designed and built for the study of materials during processing where three synchrotron techniques, SAXS, WAXS and XAS, are available simultaneously. It has been demonstrated that Rietveld refinable data can be collected from silicon SRM 640b over a 60 degrees range in a time scale of 1 s. The data have been refined to a chi(2) of 2.4, the peaks fitting best to a Pearson VII function or with fundamental parameters. The peak halfwidths have been found to be approximately constant at 0.06 degrees over a 120 degrees angular range indicating that the instrumental resolution function has matched its design specification. A quantitative comparison of data sets collected on the same isotactic polypropylene system on MPW6.2 and DUBBLE at the ESRF shows a 17% improvement in angular resolution and a 1.8 improvement in peak-to-background ratio with the RAPID2 system; the ESRF data vary more smoothly across detector channels. The time-dependent wide-angle XRD was tested by comparing a hydration reaction of gypsum-bassanite-anhydrite with energy-dispersive data collected on the same system on the same time scale. Three sample data sets from the reaction were selected for analysis and gave an average chi(2) of 3.8. The Rietveld-refined lattice parameters are a good match with published values and the corresponding errors show a mean value of 3.3 x 10(-4). The data have also been analysed by the Pawley decomposition phase-modelling technique demonstrating the ability of the station to quickly and accurately identify new phases. The combined SAXS/WAXS capability of the station was tested with the crystallization and spinodal decomposition of a very dilute polymer system. Our measurements show that the crystallization of a high-density co-polymer (E76B38) as low as 0.5% by weight can be observed in solution in hexane. The WAXS and SAXS data sets were collected on the same time scale. The SAXS detector was calibrated using a collagen sample that gave 30 orders of diffraction in 1 s of data collection. The combined XRD and XAS measurement capability of the station was tested by observing the collapse and re-crystallization of zinc-exchanged zeolite A (zeolite Zn/Na-A). Previous studies of this material on station 9.3 at the SRS were compared with those from the new station. A time improvement of 38 was observed with better quality counting statistics. The improved angular resolution from the WAXS detector enabled new peaks to be identified.

An Explanation for the Very Large Breathing Effect of a Metal–Organic Framework during CO2 Adsorption

“…In Situ Experiments: First, in situ synchrotron powder diffraction experiments were carried out with the RAPID2 [11] powder diffraction detector (material-processing beamline MPW6.2 [12]) at the Synchrotron Radiation Source (Daresbury, UK). A furnace and a capillary gas delivery system, developed at Birkbeck College [23], were used to obtain, in situ, the required starting material-dehydrated MIL-53(Cr)-and to apply smooth gradual changes in CO 2 pressure.…”

“…S1). Next, a set of in situ powder patterns were collected by using a rapid powder diffraction detector (RAPID2, [11] beamline MPW6.2 [12] at Daresbury, UK) under CO 2 pressure. The data indicates that at 2 bar the resulting solid, MIL-53LP (where LP denotes low pressure) exhibited a similar diffraction pattern to MIL-53LT.…”

Cell for Simultaneous Synchrotron Radiation X-ray and Electrochemical Corrosion Measurements on Cultural Heritage Metals and Other Materials

“…Nevertheless, the fact remains that the X-ray data come from a relatively small area of the surface, while the electrochemical data are averaged over the whole. Clearly, this is a feature of the experiments that needs to be addressed in future, for example, by using a faster sampling station such as 6.2 at SRS, 37 and integrating X-ray measurements from different regions of the surface.…”

Time-Resolved in Situ Synchrotron X-ray Diffraction Studies of Type 1 Silicon Clathrate Formation

“…The mixture was placed in a Ta crucible and heated in a steel autoclave at 600 °C for 24 hours. In situ time-resolved X-ray diffraction experiments were carried out at station 6.2 37 of the synchrotron radiation source (SRS) at Daresbury, UK using an incident beam energy of 8.856 keV ( = 1.42λ Å). The RAPID2 38 position-sensitive detector enabled medium-high angular resolution data (Δ(2θ) ~ 0.06°) to be collected on a timescale of a few seconds at each temperature using the high-T (high temperature) in situ cell.…”