硫脲对BH-4在铜电极上电化学氧化行为的影响

使用循环伏安法、电化学交流阻抗法研究了铜电极上BH4-在不同硫脲浓度时的电化学氧化行为。实验结果表明在扫描速率40 mV/s时,硫脲存在时BH4-氧化峰比没有硫脲存在时明显增大;根据DBFC电池特征设计出等效电路(R(Q(RW))),对交流阻抗实验数据进行了拟合,结果表明,该等效电路与实际测量结果基本一致,具有较高的精确性;循环伏安和交流阻抗实验均表明,适当的硫脲可抑制DBFC阳极的析氢副反应。

Electrochemical Oxidization Effect of BH-4 with Thiourea on Cu Electrode

Electrochemical oxidization effect of BH4- in the presence of thiourea on Cu electrode with cyclic voltammogram(CV) and electrochemical impedance spectra(EIS) have been studied.When the sweeping rate of CV was 40 mV/s, the results of CV experiments displayed that oxidation peak of BH4- with thiourea was markedly increased than without thiourea.Accordingly to the feature of DBFC,an equivalent circuit was proposed to fit the EIS experimental data.The fitted results indicated that the equivalent circuit(R(Q(RW))) was fitted very well with the experimental data and the results had good accuracy.Both CV and EIS experimental results showed that appropriate concentration of thiourea could inhibit the side reaction of catalytic hydrolysis of BH4- yielding H2 at DBFC anode.