This work investigates the surface chemistry of H2O2 generation on a boron-doped ultrananocrystalline diamond (BD-UNCD) electrode. It is motivated by the need to efficiently disinfect liquid waste in resource constrained environments with limited electrical power. X-ray photoelectron spectroscopy was used to identify functional groups on the BD-UNCD electrode surfaces while the electrochemical potentials of generation for these functional groups were determined via cyclic voltammetry, chronocoulometry, and chronoamperometry. A colorimetric technique was employed to determine the concentration and current efficiency of H2O2 produced at different potentials. Results showed that preanodization of an as-grown BD-UNCD electrode can enhance the production of H2O2 in a strong acidic environment (pH 0.5) at reductive potentials. It is proposed that the electrogeneration of functional groups at oxidative potentials during preanodization allows for an increased current density during the successive electrolysis at reductive potentials that correlates to an enhanced production of H2O2. Through potential cycling methods, and by optimizing the applied potentials and duty cycle, the functional groups can be stabilizedallowing continuous production of H2O2 moreefficiently compared to static potential methods.
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机译:这项工作研究了硼掺杂超纳米晶金刚石(BD-UNCD)电极上H2O2生成的表面化学。其动机是需要在资源有限的环境中用有限的电力有效地消毒液体废物。 X射线光电子能谱法用于鉴定BD-UNCD电极表面上的官能团,同时通过循环伏安法,计时库仑法和计时电流法测定这些官能团的电化学势。使用比色技术确定在不同电位下产生的H2O2的浓度和电流效率。结果表明,成膜的BD-UNCD电极的预阳极氧化可以在强酸性环境中(pH 0.5)还原电位下提高H2O2的产生。提出在预阳极氧化期间在氧化电势下官能团的电生成允许在连续电解期间在还原电势下增加电流密度,这与增加的H 2 O 2产生相关。通过电势循环方法,并通过优化施加的电势和占空比,可以稳定官能团允许更多地连续生产H2O2与静态电位方法相比效率更高。
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