铂电极B-Z反应系双电层稀疏区电势跃变对电化学振荡的影响

Influence of Potential Jump ψ Across Loose Region of Double Electric Layer upon Electro-chemical Oscillation in Pt-Electrode B-Z Reaction System

根据连续步骤间非平衡耗散的特征,定量表示了电化学步骤与扩散步骤的相对滞后性对电极反应体系耗散的贡献,建立了稀疏区电势跃变ψ的非平衡态热力学计算公式,给出了其在Boltzman分布近似下的表现形式.同时,建立了一个普适的Pt电极B-Z反应动力学模型,讨论了ψ对电极B-Z反应系状态演化动力学行为的影响,发现ψ的引入将强化该电极反应体系动力学机制的非线性程度,导致电化学振荡区的蜕变.给出了相应的计算机模拟图谱.

On the basis of a perfect analysis of the dissipations in the successive steps of a steady Pt- electrode B-Z reaction processes, the hesitation of electro-chemical step comparing with the diffusion step was expressed quantitatively by their contributions to the dissipation of electrode chemical reaction system. A theory of non-equilibrium thermodynamics of the potential jump ψ across the loose region of double electric layer was established. Consequently, an explicit formula for the calculation of 0 was given under the approximation of Boltzmann distribution. Meanwhile, a generalized dynamical model for Pt electrode B-Z reaction was suggested, by means of which the influence of ψ on the evolutionary dynamic behavior is further discussed in this paper. It turns out that the existence of ψ will further increase the non-linearity of dynamical mechanism of this electrode chemical reaction system. As one of the important results, it will degenerate the electro-chemical oscillation region. The corresponding degeneration of phase region favorable to the electro-chemical oscillation was plotted explicitly on the plane of externally controlled parameter-intrinsic parameter, simultaneously together with a computer simulation.