Urea is a small molecule produced in millions of tons per day and is ubiquitous in nature. Biological treatment is commonly used to oxidize the urea wastewater produced each day across the world, which produces additional solid waste and eliminates any potential for utilizing the stored chemical energy within. A solar waste-to-fuels concept is presented to synergistically produce hydrogen fuel from visible sunlight while remediating urea wastewaters. A cascade semiconductor-catalyst electrode assembly was designed to drive the photoconversion of urea to hydrogen. Proper band energy alignment facilitates catalyst activation via hole transfer across the semiconductor–catalyst interface. Specifically CdS-sensitized TiO2 with Ni(OH)2 urea electrocatalyst on fluorine-doped tin oxide coated glass was employed as photoanode. The steady-state response of the semiconductor–catalyst electrode is investigated in a photoelectrochemical cell, and charge transfer and recombination kinetics are elucidated to identify limiting charge-transfer reactions within the electrode architecture. Back electron transfer from semiconductor to catalyst is found to be competitive with urea oxidation reaction, which hinders steady-state photoconversion efficiency. Furthermore, the photoanode rapidly decomposes in urea electrolyte solutions as a result of the water-mediated photocorrosion of chalcogenide electrodes. Passivation of CdS with ZnS prior to catalyst deposition significantly improves open-circuit potential and photostability.

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The Australian Surf Life Saving Championships (the ‘Aussies’) were held between 31 March and 6 April 2014, at Scarborough Beach in Western Australia. The event attracted 6,000 persons including competitors, support staff and officials. It is estimated that 70,000 spectators attended the event over the seven days of competition.This article provides an overview of the Aussies, outlines its medical planning and role of the medical team, and describes the team structure. Equipment and team deployment is described. This article also identifies some of the challenges that the Aussies present to medical planners because of the unique factors which influence the number and type of patient presentations. Finally, improvement recommendations are made which outline a number of simple, yet key strategies which will improve medical planning in the future.

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