Time Resolved IR and X-Ray Simultaneous Spectroscopy: New Opportunities for the Analysis of Fast Chemical-Physical Phenomena in Materials Science

Abstract

New powerful sources and advanced analytical techniques have been considered in the last decade to face up the continuously increasing scientific demands, in particular, in materials science. As an example, nanoscience and nanotechnology researches are characterized by ultimate spatial resolution, fast and ultrafast time--resolved analysis, but the complexity of the investigated phenomena requires new analytical capabilities and new experimental techniques were introduced in the research arena. The availability all over the world of brilliant synchrotron radiation sources offers incredible opportunities. Many challenging experiments were made possible by these sources and understanding of many complex dynamical problems was obtained. Nevertheless, a strong demand of new analytical approaches, mainly based on concurrent and possibly simultaneous time-resolved experimental techniques, is emerging. Pioneering time resolved experiments combining X-ray and infrared radiation with a conventional source were performed more than a decade ago. Nowadays, many beamlines at third generation synchrotron radiation facilities are equipped with conventional sources to allow complementary techniques and the strategy of a concurrent analysis is mandatory in the investigation of many phenomena in frontier multidisciplinary researches. Moreover, new opportunities will be available by means of concurrent spectroscopic experiments investigating complex phenomena on a short timescale, from the sub-second to the microsecond time domain. We will present and discuss researches where the combination of IR and X-ray simultaneous experiments may return unique information on complex dynamical processes and phase transitions occurring in materials science. Finally, we will briefly describe the conceptual layout of a synchrotron radiation beamline to perform concurrent IR and X-ray experiments.

Chemical imaging of catalytic solids with synchrotron radiation

“…70 Alternatively and as has been recently proposed, a portion of the storage ring beam could be taken off at two points of a bending magnet to yield both IR and X-ray radiation which, if the associated technical challenges could be overcome, could be focussed to the same part of the sample, resulting in a very powerful technique combination for catalyst imaging purposes. 71,72 Following on from the last example are the combinations of X-rays with non-X-ray based techniques which normally requires the insertion of additional apparatus into the beamline. Whilst this is an already established field, from an imaging perspective it is only recently that such setups have been designed and commissioned.…”

IR and X-ray time-resolved simultaneous experiments: an opportunity to investigate the dynamics of complex systems and non-equilibrium phenomena using third-generation synchrotron radiation sources

“…The approach is certainly useful for following fast rate processes, detecting kinetic intermediates via complementary but independent observations. New time-resolved and concurrent approaches are required to characterize complex systems, and the combination of a concurrent/simultaneous analysis with a high time-resolution is a key issue to improving our understanding of phenomena evolving under non-equilibrium conditions (Bras et al, 1995;Marcelli et al, 2009a). At present, different radiation techniques are rarely carried out simultaneously mainly because of the impossibility of combining instruments and/or sources (Marcelli et al, 2009a).…”

New opportunity to investigate physico-chemical phenomena: time-resolved X-ray and IR concurrent analysis

“…This trend will be better exploited in the future when the next generation of light sources, such as the free electron lasers (FELs), will be available allowing the study and the characterization of phenomena occurring in the fs regime. The combination of a concurrent/simultaneous analysis with a high time resolution is one key issue to push forward researches and improve our understanding of complex systems and phenomena evolving under non-equilibrium conditions (Bras et al 1995;Marcelli et al 2009a). …”

“…In the real world, the atomic motion occurring at room temperature adds complexity to the structural determination of all systems, e.g., a liquid solution or a system out of equilibrium, for which it is almost impossible to obtain a complete electronic and structural characterization merely by means of a single spectroscopic method (Marcelli et al 2009a). In other words, a consistent structural and an electronic determination of a system is essentially determined by its dynamics and, a concurrent time-resolved structural characterization using X-rays and a molecular characterization using a vibrational spectroscopy appear mandatory.…”

“…In the past, time-resolved techniques have been typically performed independently. Indeed, different measurements are never carried out simultaneously because of the impossibility to combine different instruments and sources (Marcelli et al 2009a). Thanks to extremely high brilliance of the available SR sources, in particular in the X-ray region, and the availability of fast detectors, the combination of an intense X-ray beam with an IR beam to perform concurrent experiments on the same sample is now possible.…”