Diamond Annual Review 2025-26

Diamond-II will see the addition of a new beamline, SWIFT (Spectroscopy Within Fast Timescales). SWIFT will be a wiggler-based, quick-scanning EXAFS beamline dedicated to operando studies, also at micrometric scale. The three operational spectrometers are complementary in the energy ranges they cover, the size of their focused beam spots delivered to the sample, and the time resolutions they reach. This complementarity means that they can support research across many different scientific disciplines, from chemistry and catalysis through materials science, condensed matter physics, environmental and life science, energy materials and cultural heritage. The addition of SWIFT to the portfolio of beamlines will enhance the fast-scanning capabilities of the Spectroscopy Group, pushing the achievable time resolution towards the millisecond timescales. Understanding Parkinson’s Disease through gene silencing Parkinson’s disease is a progressive neurodegenerative disorder involving the loss of dopamine-producing neurons. One gene linked to a juvenile-onset form of the disease is ATP13A2, which helps cells transport ions. To investigate its role, researchers reduced ATP13A2 brain activity by using modified, neutralised viruses. This caused a 95% loss of ATP13A2 expression. The Spectroscopy Group consists of three operational beamlines: the Microfocus Spectroscopy beamline (I18), the Core Extended X-rayAbsorption Fine Structure beamline (B18), and the Versatile X-rayAbsorption Spectroscopy beamline (I20- Scanning). Spectroscopy Group After five months, they compared injected and control brain tissue. They found a 30% loss of neuron cells in the most affected region. To understand the cellular changes, they used X-ray fluorescence on the I18 Microfocus Spectroscopy beamline to map metals in thin sections of the substantia nigra, a brain region strongly affected in Parkinson’s. The results showed clear accumulation of iron and manganese in the treated brain samples, both linked to Parkinson’s-related changes. This pilot study suggests that ATP13A2 suppression can trigger early Parkinson’s- like molecular and cellular changes, although larger and longer studies are needed to confirm the findings. DOI: 10.1038/s41531-024-00757-4 Turning plastic waste into clean hydrogen Researchers are exploring a way to turn plastic waste into clean hydrogen fuel using sunlight. A study looked at combining two processes. First, common plastics such as polyethylene terephthalate, polyamides and polyurethanes are broken down using acid-catalysed depolymerisation. This turns long, stable polymer chains into smaller, more reactive molecules. These molecules are then fed into a photocatalytic system, where a light- absorbing catalyst uses solar energy to drive hydrogen production. Diamond’s B18 beamline was used for X-ray absorption spectroscopy, allowing researchers to study the catalyst during the reaction. The measurements showed that plastic-derived molecules donate electrons at the catalyst surface, while protons are reduced to form hydrogen gas. They also showed that the catalyst remained stable under reaction conditions. The work suggests a promising route to tackle two challenges at once: reducing plastic waste and producing lower- carbon hydrogen fuel. DOI: 10.1016/j.joule.2026.102347 How water unlocks hidden activity in iridium catalysts Iridium oxide is one of the best catalyst materials for proton exchange membrane water electrolysis, a technology used to produce green hydrogen. It is especially valuable because it can survive the acidic conditions inside commercial electrolysers. However, iridium is rare and expensive, so researchers need to understand how to make it work as efficiently as possible. Research conducted on the I18 beamline showed how water can “switch on” hidden activity in iridium oxide catalysts. It combined X-ray absorption spectroscopy with electrochemical measurements and compared different forms of iridium oxide under realistic operating conditions. Researchers found that water-rich, amorphous iridium oxide can be up to ten times more active than dry, crystalline forms. The water inside the material appears to help it adapt during the oxygen evolution reaction, creating highly active sites for oxygen production. The water-rich catalyst is more active but less stable, while crystalline iridium oxide is more durable but less active. Understanding this balance could help design better catalysts for large-scale green hydrogen production. DOI: 10.1021/acscatal.5c05765 21 Spectroscopy Group 22 Annual review 2025/26