Appearance of New Oscillations (Named Oscillations I and J) during Reduction of H2O2 on Platinum Electrode

作者：Mukouyama Yoshiharu^*; Kawasaki Hirokazu; Hara Daisuke; Yamada Yuri; Nakanishi Shuji

来源：Journal of the Electrochemical Society, 2017, 164(9): H675-H684.

DOI：10.1149/2.1561709jes

The reduction of H2O2 on Pt electrodes in H2SO4 solution shows various types of electrochemical oscillations, named sequentially from A to H, as has been reported previously. One of them, oscillation H, appears when Na2SO4 or K2SO4 is added to the acidic solution. In the presence of the cation dissociated from the salt, Na+ or K+, the pH at the electrode surface becomes basic during the H2O2 reduction, leading to the appearance of oscillation H. This present work demonstrates that new types of oscillations, named oscillations I and J, are also induced by the pH increase due to the cation. In contrast to oscillation H, oscillations I and J also appear when the H2O2 reduction occurs on Pt electrodes in NaOH solution. They are caused by an N-shaped negative differential resistance (N-NDR) induced by the formation of under-potential deposited H. Oscillation I appears in the potential region of the N-NDR, whereas oscillation J appears at potentials more negative than the N-NDR region, i.e., at potentials where hydrogen evolution reaction occurs. Detailed studies reveal that oscillations I and J are classified into an N-NDR and a coupled N-NDR (CN-NDR) oscillator, respectively.

• 出版日期2017