Acta Phys. -Chim. Sin. ›› 2014, Vol. 30 ›› Issue (4): 686-692.doi: 10.3866/PKU.WHXB201402142

• ELECTROCHEMISTRY AND NEW ENERGY • Previous Articles     Next Articles

Model Simulation and Analysis of Spatiotemporal Dynamics for the Electro-Oxidation of Sulfide on Platinum

YANG Jia-Ping, YU Hui-Yao, HE Yu-Xiu, XIE Jing-Xuan, BI Wen-Yan, GAO Qing-Yu   

  1. College of Chemical Engineering, China University of Mining and Technology, Xuzhou 221116, Jiangsu Province, P. R. China
  • Received:2013-12-06 Revised:2014-02-09 Published:2014-03-31
  • Contact: GAO Qing-Yu E-mail:gaoqy@cumt.edu.cn
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (21073232, 51221462), Fundamental Research Funds for the Central Universities, China (2013XK05), Priority Academic Program Development of Jiangsu Higher Education Institutions and the Program for Graduate Research and Innovation in Universities of Jiangsu Province, China (CXLX13-947).

Abstract:

Based on the reaction mechanism of the electro-oxidation of sulfide on platinum, we propose a simplified model for studying the spatiotemporal dynamics on the electrode surface in the oscillatory region of the N-shaped negative differential resistance (N-NDR) through numerical simulation. Simple and complex current oscillations were observed during the homogeneous simulation, and these were caused by coupling between one positive feedback, i.e., double-layer potential autocatalysis, and two negative feedbacks consisting of a mass-transport limited step and a poison-adsorption process. To obtain a better simulation of the experimental situation, the transport of electroactive species in both the parallel and vertical directions of the electrode was taken into account to simulate pattern formation on the electrode. The model simulations gave complicated patterns including twinkling-eye patterns and traveling waves, which agree qualitatively with the experimental results and possess the same evolution principles. Meanwhile, for certain parameters more complex patterns were obtained, e.g., two-arm spiral waves of the double-layer potential. This opens an interesting perspective in the explanation and prediction of pattern formation in electrochemical systems.

Key words: N-shaped negative differential resistance, Oscillation and complex oscillation, Pattern formation, Electrochemical oxidation of sulfide, Model simulation

MSC2000: 

  • O646