Voltammetric probing of pH at carbon nanofiber–Nafion™–carbon nanofiber membrane electrode assemblies
Voltammetric probing of pH at carbon nanofiber–Nafion™–carbon nanofiber membrane electrode assemblies
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碳纳米纤维–Nafion™–碳纳米纤维膜电极组件的 pH 伏安法探测
DOI：
10.1016/j.electacta.2011.11.095
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发表时间：
2012
影响因子：
6.6
通讯作者：
F. Marken
中科院分区：
文献类型：
--
作者：
R. A. Webster;F. Xia;M. Pan;Shichun Mu;Sara Dale;S. Tsang;F. Hammett;C. Bowen;F. Marken
开发了使用碳纳米纤维膜电极组件(CnMEA)在无支撑的液体或气体介质中进行三电极电化学测量的方法。将碳纳米纤维膜(厚度约20μm)从两侧热压到Nafion™离子导体膜(厚度约50μm)上。所得到的cnMEA被用作对苯二酚在(I)0.5M、(II)0.05M和(III)0.005M NaHCO3水溶液中以及(Iv)在纯除盐水中的对电极和工作电极(带有外部SCE参比电极)。获得了明确的伏安响应，并研究了pH的影响。然后将cnMEA工作电极和SCE参比电极之间的气体-盐(二铵硫酸盐)接触用于气体流动系统中，以获得在潮湿气体(相对湿度为80%的氮气)下的伏安响应。对苯二酚的可逆氧化还原循环进行了验证，并观察到了湿度和pH的影响。探讨了氨气对法拉第电流的影响。伏安测量提供了对MEA过程和条件的直接了解。
Methods are developed for using a carbon nanofiber membrane electrode assembly (cnMEA) for three-electrode electrochemical measurements in unsupported liquid or gaseous media. The carbon nanofiber membrane (ca. 20μm thickness) is hot-pressed from both sides onto a Nafion™ ion conductor film (ca. 50μm thickness). The resulting cnMEA is employed as both a counter electrode and working electrode (with an external SCE reference electrode) for the liquid phase oxidation of hydroquinone in (i) 0.5M, (ii) 0.05M, and (iii) 0.005M aqueous NaHCO3, and (iv) in pure demineralised water. Well-defined voltammetric responses are obtained and pH effects are investigated. A gas–salt (di-ammonium sulphate) contact between the cnMEA working electrode and SCE reference electrode is then employed in a gas flow system to obtain voltammetric responses in contact with a humidified gas (N2, 80% relative humidity). Reversible redox cycling of entrapped hydroquinone is demonstrated and humidity and pH effects are observed. Ammonia gas effects on Faradaic currents are explored. Voltammetric measurements provide direct insight into the MEA processes and conditions.
盐基质伏安法：氯化铵的微相氧化还原过程|
影响因子：
5.4
作者：
Dale S
通讯作者：
Dale S