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This dissertation, "Properties of Nickel and Antimony Doped Tin Oxide Electrode Material in Relation to Electrochemical Generation of Ozone" by Bin, Wang,, was obtained from The University of Hong Kong (Pokfulam, Hong Kong) and is being sold pursuant to Creative Commons: Attribution 3.0 Hong Kong License. The content of this dissertation has not been altered in any way. We have altered the formatting in order to facilitate the ease of printing and reading of the dissertation. All rights not granted by the above license are retained by the author. Abstract: In this study, the properties of nickel and antimony doped tin oxide (NATO) electrode materials were investigated in relation to the electrochemical generation of ozone. The performance of NATO materials was correlated to -OH radical generation and oxygen adsorption properties. Long-time ozone generation results suggested that surface property changes, including surface morphology, chemical composition and electro-catalyst thickness, could lead to ozone production rate decreased from 137 to 0 mg-h-1 and the current efficiency declined from 18% to 0. The loss of Ni in the electrode was suggested for the decrease in ozone generation. Moreover, material characterization results indicated the presence of NiOOH and multiple oxidation states of Sb (+3 and +5), which were proposed as the critical sites for the electrochemical generation of ozone. In addition, NATO nanocrystals of 3.5 7.5 nm in size prepared by the hydrothermal method were used as an alternative route to fabricate electrodes. The highest current efficiency of 41% was achieved on NATO material of 6% Sb in the precursor, which led to the lowest resistivity of 2.38 0.03 Ω-cm in the product NATO material. This further demonstrated the applicability of NATO materials used as electro-catalysts for the electrochemical generation of ozone. Hydroxyl free radicals (-OH) can be regarded as one of the most important intermediates for ozone genera