甲酸Pt电极电化学氧化体系中时间自组织导致的可利用功耗失  

Useful Power Loss Led by Temporal Self-organization Appearing in Electro-chemical Oxidation System of Formic Acid on Pt-electrode

作　　者：林风[1] 罗久里[1] 

机构地区：[1]四川大学化学学院,化学物理研究所,成都610064

出　　处：《高等学校化学学报》2011年第6期1384-1388,共5页Chemical Journal of Chinese Universities

基　　金：国家自然科学基金(批准号:20673074)资助

摘　　要：在电极化学反应步骤为控制步骤的条件下,对甲酸阳极氧化体系中出现的电化学振荡的阈值及跨越阈值后状态演化的极限环路径进行了系统动力学计算.同时,根据非平衡电极过程的耗散-涨落理论,进一步对跨越振荡阈值前后的临界区与电化学震荡区的极化曲线及功耗谱进行了随机热力学分析计算.研究结果表明,跨越临界区后单位电化学反应功耗谱出现突降;随着时间自组织的出现,虽然周期平均单位反应功耗随电流密度的增大而增大,但在较大的范围内保持在低于阈值前小电流恒稳电极过程功耗的水平.In this paper both the threshold of potential oscillation and the trajectories of limit cycle beyond it in the electrochemical oxidation system of formic acid on Pt-electrode were analyzed and computed by nonlinear systematical dynamics under the assumption that the electrochemical reaction steps are dominate.Furthermore,by means of the dissipation-fluctuation theory of polarization based on stochastic thermodynamics the polarization curves,as well as the spectrum of power loss in both the critical regime and the temporal self-organization regime were also obtained.It turns out that the spectrum of power loss per unit electrochemical reaction will abruptly decrease during the current density（externally controlled） crossing its threshold（Hopf bifurcation point）.Following with the appearance of the temporal self-organization the average power loss per unit electrochemical reaction per period still increase with the current,however it keeps at a level lower than that before threshold until the current arrives to certain high extent.

关 键 词：甲酸电化学氧化 电化学耗散 电化学极化 不可逆电极过程的时间自组织 可利用功耗失 

分 类 号：O642.12[理学—物理化学]