Measurement of Chemical Impedance for Interface of Electrocatalysis with Servo-analyzer Method and its Applications.

伺服分析仪法测量电催化界面化学阻抗及其应用。

• 批准号: 62550599
• 负责人: YAMASHITA Masamichi
• 金额: $ 1.15万
• 依托单位: Doshisha University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1987
• 资助国家: 日本
• 起止时间: 1987 至 1988
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-62550599/
• 关键词: Chemical impedance; Frequency response analysis (FRA); Three dimensional Cole-Cole plot; Electrocatalysis for a sodium tetrahydroborate fuel cell; Nickel-Palladium alloy catalysis; Evaluation of electrocatalytic activity; サーボ・アナライザー法; ケミカルインピーダンス /

Technical method for chemical impedance measurement has been established with servo-analyzer and the electrocatalytic activity of fuel cell electrodes is estimated. 1. Applicability of a frequency response analyzer (FRA) impedance method: (1) Three dimensional Cole-Cole plots have been obtained by use of the FRA impedance method. (2) According to expression of rudimentary processes (such as transfer, diffusion, and film formation), the comples plane pictures a hemicircle, the diameter of which is proportional to the resitance of transfer reaction and/or film formation on the electrode. 2. Evaluation of electrocatalytic activity of the anode for a fuel cell with the FRA impedance method: (1) Tetrahydroborate is expected to be favorable anodic active mass for the fuel cell because of its good stability in alkaline solutions and negative potential on the anode. In order to study the electrocatalytic activity during the anodic oxidation of the fuel, the FRA impedance method has been carrie … More d out on Ni, Ni-Pd, and Pd anodes at -0.7 V (vs,Hg/HgO in 5M-NaOH) where the region of passivation of Ni in the alkaline solutions. (2) From results of the FRA analysis, two hemicircles were included in the complex-plane of impedance diagram (Cole-Cole plot) for the Ni-Pd anode. This pattern may be explained in terms of both the oxidation of the fuel at the anode in a high-frequency part and an oxide film formed on the surface in a low-frequency part of the diagram. The formation of the oxide film was inhibited with increasing the Pd content of the alloy. However, for the Ni-Pd alloy anode, the discharge current density decreased gradually in comparison with that of the Ni electrode. (3) The electrocatalytic effect of added Pd is shown that the discharge current density was increased on the alloy electrode containing 2.5atom%-Pd and it was decreased rapidly more than the addition of 2.5atom%-Pd. It is concluded that the nickel hydroxide, which was observed on the surfaces of both Ni and Ni-Pd anodes after discharge from ESCA spectra, contributes to the deactivation of the electrocatalytic activity, whereas the Ni-2.5atom%Pd alloy will increase it during discharge at -0.7V. The FRA impedance method facilitates to estimate the electrocatalytic activity. Less

建立了用伺服分析仪测量化学阻抗的技术方法，并对燃料电池电极的电催化活性进行了评价。1.频率响应分析仪（FRA）阻抗法的适用性：（1）利用FRA阻抗法得到了三维Cole-Cole图。(2)根据基本过程（如转移、扩散和成膜）的表达，复平面描绘了一个半圆，其直径与电极上的转移反应和/或成膜的电阻成正比。2. FRA阻抗法评价燃料电池阳极的电催化活性：（1）四氢硼酸盐在碱性溶液中稳定性好，阳极电位为负电位，有望成为燃料电池良好的阳极活性物质。为了研究燃料阳极氧化过程中的电催化活性，采用FRA阻抗法， ...更多信息 在-0.7V（vs，5 M-NaOH中的Hg/HgO）下，在Ni、Ni-Pd和Pd阳极上，其中Ni在碱性溶液中的钝化区域。(2)根据FRA分析的结果，Ni-Pd阳极的阻抗图（Cole-Cole图）的复平面中包括两个半圆。该图案可以根据图中高频部分中阳极处燃料的氧化和低频部分中表面上形成的氧化物膜来解释。随着合金中Pd含量的增加，氧化膜的形成受到抑制。然而，对于Ni-Pd合金阳极，与Ni电极相比，放电电流密度逐渐降低。(3)结果表明，添加2.5atom%-Pd的合金电极放电电流密度比添加2.5atom%-Pd的合金电极放电电流密度大，但放电电流密度比添加2.5atom%-Pd的合金电极放电电流密度小。结果表明，在-0.7V放电过程中，Ni-2.5atom%Pd合金的加入使Ni和Ni-Pd阳极的电催化活性降低，而Ni-2.5atom%Pd合金的加入则使Ni和Ni-Pd阳极的电催化活性增加。FRA阻抗法有助于评价电催化活性。少

项目成果

山下正通: 日本化学会誌. 8. 1384-1390 (1988)

山下正道：日本化学会杂志 8. 1384-1390 (1988)。

Masamichi YAMASHITA.: Extended Abstracts,172nd Meeting of The Electrochemical Society,Inc.87-2. 244 (1987)

Masamichi YAMASHITA.：扩展摘要，电化学学会第 172 次会议，Inc.87-2。

Masamichi YAMASHITA: "Evaluation of Electrocatalysis for Fuel Cell with Frequency Response Analyzer (FRA) Impedance Method (I)" Extended Abstracts, Spring Meeting of The Chemical Society of Japan. I. 374 (1988)

Masamichi YAMASHITA：“使用频率响应分析仪 (FRA) 阻抗方法评估燃料电池电催化作用 (I)”扩展摘要，日本化学会春季会议。

Masamichi Yamashita: Progress in Batteries & Solar Cells. 7. (1988)

山下正道：电池的进展

A.Salkind,J.P.Gobano,K.Fueki,R.J.Brodd,A.Takenhara,A.Kozawa / T.Osaka,M.Yamashita,I.Uchida,Y.Sato,N.Koura: "Progress in Batteries & Solar Cells" JEC Press Inc., C.400 (1988)

A.Salkind、J.P.Gobano、K.Fueki、R.J.Brodd、A.Takenhara、A.Kozawa / T.Osaka、M.Yamashita、I.Uchida、Y.Sato、N.Koura：“电池的进展