Abstract
Small-angle X-ray scattering (SAXS) is a well-established, versatile technique for the analysis of nanoscale structures and dimensions, e.g., in liquid dispersions, thin solid objects or powder samples. When combined with wide-angle X-ray scattering (WAXS), complementary information about the atomic structure can be obtained. SAXS experiments traditionally require dedicated instruments to achieve the desired angular resolution, sensitivity, stability, and speed of measurement. Here we demonstrate how a multi-functional laboratory goniometer platform, as widely being used for powder X-ray diffraction and for a variety of related techniques, can be configured with pre-aligned X-ray modules that enable advanced SAXS/WAXS experiments, without compromising the exceptional versatility of the instrument. Line and point collimation setups, as well as quick and easy switching between them, are readily possible. Key components are a detachable, evacuated beam path and a high-resolution, low-noise hybrid pixel area detector, in combination with a hardware interface design that allows to configure the instrument with different X-ray modules without the need for re-alignment. Software for SAXS data reduction and analysis was developed. The good SAXS/WAXS performance and the derived analytical results were verified on various test samples, such as gold nanoparticles, colloidal silica, liposomes, dilute protein solutions, and solid polymer samples. It is believed that this novel approach to SAXS/WAXS instrumentation will help to make this powerful structure analysis technique more widely accessible and affordable for multi-user laboratories.
Highlights
From the required instrumentation point of view, the Small-angle X-ray scattering (SAXS) technique is challenging
It was shown by Bolze et al.8 and Bota et al.9 that basic SAXS and wide-angle X-ray scattering (WAXS) measurements are possible on a typical, goniometer-based X-ray diffraction instrument by making use of suitable X-ray optics and dedicated attachments
We describe the details of the experimental setup for SAXS and WAXS and demonstrate its good performance on a variety of test samples
Summary
From the required instrumentation point of view, the SAXS technique is challenging. The intensity of X-rays that is scattered by a given sample must be measured as a function of the scattering angle 2θ, in very close proximity to the direct beam, with a 2θmin < 0.1◦ [or qmin < 0.08 nm−1, where q denotes the scattering vector q = 4π λ−1 sin(θ), and λ denotes the wavelength of radiation]. In-house SAXS/WAXS instruments enable measurements once a sample is freshly prepared and in many cases yield a high data quality that may already be sufficient for the given purpose It was shown by Bolze et al. and Bota et al. that basic SAXS and WAXS measurements are possible on a typical, goniometer-based X-ray diffraction instrument by making use of suitable X-ray optics and dedicated attachments. Such an experimental approach could achieve a remarkably good small-angle resolution with a 2θmin of 0.08◦ (qmin = 0.06 nm−1) or even below, as well as a low level of background scattering. We describe the details of the experimental setup for SAXS and WAXS and demonstrate its good performance on a variety of test samples
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
