Turbo-XAS: dispersive XAS using sequential acquisition

Abstract

A new experimental technique for time-resolved X-ray absorption studies in the sub-second range has been successfully tested on the dispersive XAS beamline (ID24) at the ESRF. It consists of a sequential acquisition of energy points using the dispersive optics scheme installed on the beamline. Turbo-XAS takes full advantage of the properties of third-generation radiation sources, overcoming many of the problems encountered in the classical dispersive XAS mode, based on position-sensitive detectors. The new technique bene®ts from the basic assets of the dispersive set-up, i.e. the absence of movement of the optics and the extremely small and stable horizontal focal spot. In addition, it features simultaneous recording of I 0 and I 1 and the possibility of performing¯uorescence and electron detection.

μXANES study of iron redox state in serpentine during oceanic serpentinization

“…Only one of the three undulators was used to prevent heat-load of the optics. Point analysis and hyperspectral XANES micro-mapping were collected using a pindiode fluorescence detector positioned at 90°from the incident X-ray beam (see Muñoz et al, 2006Muñoz et al, , 2008, and in the Turbo-XAS setup (Pascarelli et al, 1999. The position of the sample, perpendicular to the X-ray beam, allows minimizing self-absorption (Pfalzer et al, 1999).…”

The Time-resolved and Extreme-conditions XAS (TEXAS) facility at the European Synchrotron Radiation Facility: the energy-dispersive X-ray absorption spectroscopy beamline ID24

“…The micro-XAS station for two-dimensional hyperspectral mapping. A micro-XAS station optimized for twodimensional hyperspectral mapping of heterogeneous samples in transmission mode or in fluorescence mode using sequential acquisition (Pascarelli et al, 1999) is available in EDXAS_S. This facility (shown in Fig.…”

Advancing Time-resolved Methods in Monitoring and Characterization of Catalysts

“…However, due to the aberration of the focussed beam, energy dispersive measurements require that the sample is very homogeneous, which is a severe problem in the case of polycrystalline, real catalyst samples [8]. Furthermore, DEXAFS cannot make direct use of fluorescence detection, which is important in the case of dilute catalytically active species, unless a sequential QEXAFS-like acquisition approach is used [9]. The QEX-AFS method, however, can conveniently be applied to samples used for standard XAFS experiments and offers excellent time resolution.…”