Diamond Light Source - Annual Review 2022/23

40 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 2 / 2 3 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 2 / 2 3 Imaging andMicroscopy Group Paul Quinn, Science Group Leader T he Imaging and Microscopy Group brings together eight experimental facilities (I08, I08-1, DIAD, I12, I13-1, I13-2, I14 and ePSIC) which use electrons and X-rays to image samples under different experimental conditions across a diverse range of length scales and time scales. The DIAD beamline for Dual Imaging and Diffraction offers two X-ray techniques, full-field radiography/tomography and micro-diffraction, used on the same sample quasi-synchronously. This setup enables in-situ characterisation of the 3D microstructure of the material at the same time as its crystallographic phase and/or strain state. X-rays from a 10-pole wiggler are split into two independent beams and then combined at the sample position. Imaging beam can be operated in either pink or monochromatic mode; diffraction is conducted withmonochromatic mode. Both beam energies can be chosen independently of each other in an energy range of 8-38 keV. DIAD expects the delivery of a dedicated mechanical test rig with integrated tomography capabilities which will be an integral part of the end station and enable a variety of scientific experiments in engineering, materials science, biomaterials and hard tissues, geology and mineralogy. DIAD is part-funded by the University of Birmingham. The Scanning X-ray Microscopy (SXM) beamline (I08) is for morphological, elemental and chemical speciation on a broad range of organic-inorganic interactions in a 250 - 4400 eV photon energy range, and sample investigations under ambient or cryogenic conditions. I08 has a range of applications including biological and biomedical sciences, earth and environmental science, geochemistry, andmaterials science. I08 improved and partially automated and simplified User operation. The new soft X-ray spectro- and tomo-ptychography branchline will provide a step change in imaging and spectro-microscopic performance for soft X-ray imaging at Diamond. The branchline is growing in capabilities and has been enthusiastically received by initial users (I08-1 took first users in Oct 2020) with clear benefits for experiments for many experiments transitioning from I08 to I08-1. Key developments for I08-1, such as providing access to the carbon edge for ptychographic studies are well under way and developments to deliver tomographic and cryogenic capabilities are also planned for the next year. Applications for user experiments are now accepted through our standard call. The Joint Engineering, Environmental and Processing (JEEP) beamline (I12) uses a 4.2 T superconducting wiggler to provide polychromatic and monochromatic X-rays in the energy range 53 to 150 keV. These high photon energies provide good penetration through large or dense samples. The beamline offers beam sizes ranging from 50 x 50 μm 2 for diffraction, up to 90 x 25 mm 2 for imaging and tomography. Static objects larger than the available beam can be tomographically imaged using special scanning protocols. The beam characteristics enable the study of macroscale samples that are representative of bulk materials and processes. Another feature of I12 is the ability to use complex, enclosed sample environments without unacceptable attenuation of the beam. X-ray techniques available are radiography, tomography, energy-dispersive diffraction, monochromatic 2D diffraction and scattering. Radiography and tomography are performed predominantly with monochromatic X-rays. Polychromatic beam is reserved for energy-dispersive diffraction or non-routine special requests. I12 has a diverse user community (materials science & engineering; chemical processing; biomedical engineering; geoscience; environmental science; physics; palaeontology) who make full use of the beamline’s capabilities. The beamline’s two flexible experimental hutches allow users to bring their own rigs and sample chambers. I12 continues to support a wide range of in situ , time resolved experiments, notably in additive manufacturing, materials property testing and chemical processing. It is common for users to combine imaging and diffraction in the same experiment. Almost all tomography scanning is done with constant speed stage rotation, to reduce scan times. The I13 Imaging and Coherence beamline is for multi-scale imaging in the energy range of 6 -30 keV. The achievable resolution ranges fromseveral microns to some tens of nanometers with two branchlines operating independently for this purpose. The DiamondManchester Imaging branchline performs mainly in- line phase contrast tomography with a strong emphasis on dedicated sample environments. A full-fieldmicroscope using Zernike phase contrast imaging over a field of viewof 50-100 μmand a resolution of 50 - 100 nm is in operation, with a growing user community, allowing us to identify nano-sized structures under dynamic conditions. A broad set of user groups are now exploiting the robot arm facility for static samples and high-throughput studies. The highest spatial resolution, of 30 nm, is achieved on the coherence branch with ptychographic imaging. Ptycho-tomography scans can be performed on a time scales of hours and this is enabling new spectroscopic and dynamic experiments. Bragg- CDI and new developments in Bragg Ptychography provide complementary experimental capabilities for studying nano-crystalline structures . I14, the Hard X-ray Nanoprobe beamline, offers a beam of 50 nm for high resolution imaging. I14 has expanded the core 2D techniques of X-ray fluorescence, diffraction, X-ray Absorption Near Edge Structure (XANES), differential phase contrast and ptychography for mapping inhomogeneities in a wide range of samples to include tomography for volume imaging of elemental, structural and chemical states. A wider range of complex in-situ experiments in a range of conditions such as electrochemistry, liquid and gas environments have been enabled by dedicated effort to expand the sample cells available and optimise the measurement conditions. . The electron Physical Science Imaging Centre (ePSIC) at Diamond consists of two transmission electronmicroscopes, a JEOL ARM200 and a JEOL GRAND ARM 300, which were brought to Diamond through a collaboration with Johnson Matthey and the University of Oxford respectively. The ARM 200 is a state-of- the-art probe-corrected analytical microscope capable of atomic resolution electron energy loss and X-ray spectroscopy. The ARM 300 is a dedicated imaging instrument aligned across a wide range of accelerating voltages (30 - 300 keV) and is equipped with an Oxford Instruments X-Max 100 EDX detector. It is both probe- and imaging-corrected and has numerous detectors, including a small pixel array (512 x 512) fast direct electron detector for low voltage work and a newly installed large pixel array (4K x 4K) fast direct electron detector for high voltage imaging. These combined capabilities make this a unique resource for electronmicroscopywithin the UK.With in situ sample holders, users at ePSIC can perform variable temperature measurements from 100 to 1600 K, apply electrical bias to samples during imaging and transfer samples anaerobically into the microscope. For TEM sample preparation ePSIC runs a JEOL 4700F focused ion beam microscope with in-situ lift out and anaerobic transfer capability. The state-of-the-art instrumentation available at ePSIC attracts both established electron microscopists looking to develop new techniques, and scientists with limited previous electronmicroscopy experience interested in the atomic structure of their samples. ePSIC is moving to a 3-month peer review cycle to be able to respond more quickly to science needs and to also provide a mechanism to improve correlative experiments, enabled by the unique co- location of ePSIC at Diamond. ePSIC is moving to a 3-month peer review cycle to be able to respondmore quickly to science needs and to also provide amechanism to improve correlative experiments, enabled by the unique co-location of ePSIC at Diamond Figure1: The I14 team in the experimental hutch Figure 2: I12 team and support staff on the beamline (experimental hutch 1 and 2).