Mark Symes was born in London in 1982 and graduated from the University of Cambridge in 2005. After a PhD at the University of Edinburgh with David A. Leigh (FRS), he undertook postdoctoral studies at the Massachusetts Institute of Technology (2009-2010). In late 2010, he returned to the UK and became a postdoctoral researcher at the University of Glasgow. This didn't put them off though, and he joined the faculty at Glasgow in 2013. Since 2016 he has held a Royal Society University Research Fellowship at Glasgow. His research interests span energy conversion, small-molecule activations, electrochemistry, and electrocatalysis. Alex Wallace was born in Swindon in 1993 and graduated with a BSc in Chemistry (first class) from the University of Southampton in 2015. It was in Southampton that he developed a deep interest in electrochemistry, which led him to undertake further study by way of the world's first MSc in Electrochemistry at Southampton, from which he graduated in 2016 with Distinction. Hungry for more electrochemistry, he then immediately joined the Symes group at the University of Glasgow. His research interests include water electrolysis, sonoelectrochemistry, and electrochemistry in ionic liquids.

Electrolysis is seen as a promising route for the production of hydrogen from water, as part of a move to a wider “hydrogen economy”. The electro-oxidation of renewable feedstocks offers an alternative anode couple to the (high-overpotential) electrochemical oxygen evolution reaction for developing low-voltage electrolysers. Meanwhile, the exploration of new membrane materials is also important in order to try and reduce the capital costs of electrolysers. In this work, we synthesise and characterise a previously unreported anion-exchange membrane consisting of a fluorinated polymer backbone grafted with imidazole and trimethylammonium units as the ion-conducting moieties. We then investigate the use of this membrane in a lignin-oxidising electrolyser. The new membrane performs comparably to a commercially-available anion-exchange membrane (Fumapem) for this purpose over short timescales (delivering current densities of 4.4 mA cm−2 for lignin oxidation at a cell potential of 1.2 V at 70 °C during linear sweep voltammetry), but membrane durability was found to be a significant issue over extended testing durations. This work therefore suggests that membranes of the sort described herein might be usefully employed for lignin electrolysis applications if their robustness can be improved.

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The electro‐oxidation of sulfate solutions is a well‐established route for the generation of powerful oxidants such as persulfate. Despite this, the effects of simultaneous ultrasound irradiation during this process has attracted little attention. Herein, we investigate the effects of a low‐intensity ultrasonic field on the generation of solution‐phase oxidants during the electro‐oxidation of sulfate solutions. Our results show that at high current densities and high sulfate concentrations, ultrasound has little effect on the Faradaic and absolute yields of solution‐phase oxidants. However, at lower current densities and sulfate concentrations, the amount of these oxidants in solution appears to decrease under ultrasonic irradiation. A mechanism explaining these results is proposed (and validated), whereby anodically‐generated sulfate and hydroxyl radicals are more effectively transported into bulk solution (where they are quenched) during sonication, whereas in the absence of an ultrasonic field these radicals combine with one another to form more persistent species (such as persulfate) that can be detected by iodometry.