Diamond Annual Review 2023/24

41 D I A M O N D L I G H T S O U R C E A N N U A L R E V I E W 2 0 2 3 / 2 4 Revolutionising research: DIAD delves into dentistry Diamond is home to an ever-evolving array of beamlines and instruments, allowing scientists from a wide variety of disciplines to collect high-quality, high-resolution data for their groundbreaking research. In materials science, X-ray imaging and tomography experiments can determine the 3Dmicrostructure of samples, while X-ray diffraction techniques offer the phase composition and stress distribution. Most synchrotron beamlines are designed to offer one or the other, with a few that can do both – but not at the same time. Switching between the modes can be complicated and time consuming. Diamond’s Dual Imaging and Diffraction beamline (DIAD) provides both imaging and diffraction capabilities in one instrument. Its novel dual beam design operates with two independent beams meeting at the sample position, one setup for imaging and one for diffraction. By constantly switching between the two modes, DIAD enables in situ and in operando measurements and time- resolved studies. Synchrotron techniques are key to understanding the complex microstructure of tooth enamel. Understanding the complex structure of tooth enamel, the factors involved in its decay and potential strategies for its remineralisation exemplify some outstanding tasks in biomedical materials science that can benefit from the dual beamline approach. A group of researchers from the University of Oxford and the University of Birmingham (led by Professor Alexander Korsunsky) detail a proof-of-concept study that demonstrated how the unique capabilities of DIAD can be used to consider different options for remineralisation and to grade them in terms of how well they work. The team were able to achieve collocation and correlation between WAXS (wide-angle X-ray scattering), 2D (radiographic), and 3D (tomographic) imaging. X-ray imaging in 2D or 3D modes offers details of the sample microstructure, with X-ray scattering data adding nanoscale and ultrastructural information such as phase and preferred orientation (texture). Besnard, C. et al. DOI:10.1021/cbmi.3c00122 Carbon nanotubes allow next-gen semiconductor synthesis While indium selenide (In x Se y ) semiconductors have desirable properties that offer potential applications in photovoltaic and optoelectronic devices, these materials exhibit complex polymorphism, and different phases have different physical and chemical properties. Previous research has shown that confining indium selenide to two dimensions significantly alters its physical properties and could make it suitable for high-quality semiconducting components in future devices. In 2 Se 3 nanowires (measuring between 40 and 200 nm wide) maintained the intricate phase-change behaviour, high photosensitivity and rapid photoresponse, but lack some of the exciting properties of single-layer InxSey. However, creating 2D sheets of indium selenide is challenging, typically requiring liquid-phase or mechanical exfoliation. Researchers from the University of Nottingham synthesised In x Se y in single-walled carbon nanotubes (SWCNTs), which offer a unique environment for the templated growth of ultrathin nanomaterials. They used the electron Physical Science Imaging Centre (ePSIC) to demonstrate that aberration- corrected transmission electron microscopy (AC-TEM) allows identification of the phase of the encapsulatedmaterial. It allows them to see atoms, see where they were, and therefore checked what type of polymorph was created. Their study demonstrates a robust method for synthesising two different phases of ultrathin In x Se y nanoribbons, offering the potential for future production of bespoke and versatile nanoelectronic devices. Cull, W.J. et al. DOI:10.1021/acsnano.3c00670 Figure: (a) Structural model of monolayer InSe in the (110) orientation. (b) Three-part composite image of an InSe nanoribbon inside a SWCNT, consisting of an AC-TEM image (left), a simulated TEM image (center), and molecular model (right). (c, d) Electron density profile maps in red, generated from the red line superimposed over the experimental AC-TEM image in (b), and in blue, generated from the blue line superimposed over the simulated TEM image in (b), with calculated interatomic distances highlighted in nm. (e–h) The same as (a–d), respectively, but for the (001) orientation of the same nanoribbon. Figure: Graphical abstract of the publication.