Grazing Incidence Small Angle X-Ray Scattering as a Tool for In- Situ Time-Resolved Studies

Abstract

With the advent of third-generation synchrotron sources and the development of fast two-dimensional X-ray detectors, X-ray scattering has become an invaluable tool for insitu time-resolved experiments. In the case of thin films, grazing incidence small angle X-ray scattering (GISAXS) constitutes a powerful technique to extract morphological information not only of the thin film surface but also of buried structures with statistical relevance. Thus, recently in-situ GISAXS experiments with subsecond time resolution have enabled investigating the self-assembly processes during vacuum deposition of metallic and organic thin films as well as the structural changes of polymer and colloidal thin films in the course of wet deposition. Moreover, processing of thin films has also been investigated in-situ employing GISAXS. In this chapter, we review the current trends of time-resolved GISAXS studies. After an introduction to the GISAXS technique, we present exemplary results of metallic and organic thin film preparation, wet deposition of polymer thin films and self-assembly of colloidal thin films, as well as examples of thin film modification in, e.g., microfluidic channels and within working devices. Finally, an overview of the future perspectives in the field is provided.

Material properties particularly suited to be measured with helium scattering: selected examples from 2D materials, van der Waals heterostructures, glassy materials, catalytic substrates, topological insulators and superconducting radio frequency materials

“…107 In a study of highly proton-ordered water structures on oxygen pre-covered Ru(0001) it could be shown that the atomic oxygen and the oxygen from water form a (2 Â 2) surface reconstruction, which however, is broken by the hydrogen to give a (2 Â 4) surface reconstruction: while LEED measured a (2 Â 2), HAS measured a (2 Â 4) superstructure. 108 3.6 HeSE: a unique tool for studying surface dynamics Helium spin-echo (HeSE) is a recent variation on the HAS technique 109,110 which adds manipulation of the helium wavepackets using the nuclear spin of 3 He atoms, to enable dynamical measurements to be obtained in a completely different way. Essentially, each helium wavepacket is split into two spin-components, which are separated by a time, t SE , using a magnetic field, before they scatter in turn from the surface being studied.…”

“…The top inset shows a typical measurement with the linewidth caused by a small Doppler broadening upon scattering from moving adsorbates and thus corresponding to the timescale of the molecular movement. 111 Since the process is based on self-interference of each 3 He atom, the polarisation loss depends only on the change in energy and not the beam energy itself. 109 Fig.…”

“…The penetration depth is determined by the interaction potential between the scattering probe and the sample in combination with the probe energy: electrons, X-rays and neutrons all scatter off the electronic cloud of the atomic cores and atomic nuclei in the sample, and always have a certain penetration into the bulk. Specific methods have been developed to enhance the surface sensitivity of the techniques: low energy electron diffraction, 1 grazing incidence wide angle X-ray scattering, 2 grazing incidence small-angle X-ray scattering 3 and grazing incidence small-angle neutron scattering, 4 but a certain penetration always remains for these probes.…”

Grazing Incidence Small-Angle Neutron Scattering: Background Determination and Optimization for Soft Matter Samples

“…According to Ref. [29] the diffuse scattered intensity (that accompanies the specular reflection) coming from lateral scattering length density fluctuations with intensity:…”

Operando monitoring the nanometric morphological evolution of TiO2 nanoparticles in a Na-ion battery

“…In the last decade, in-situ and operando Small-Angle X-Ray Scattering (SAXS), either in transmission or grazing incidence geometries, has become a very powerful tool for the characterization of nanoscale phenomena during material preparation and processing as well as on working devices [22, 23] with a time resolution in the millisecond regime [24]. These experiments have facilitated a deeper understanding of, e.g., the underlying kinetics of drying colloidal droplets [25, 26] and nanoparticle formation [27, 28], the morphological evolution during thin film preparation and processing [29–32] or the correlation between polymer solar cell efficiencies and morphology [33].…”