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当一针尖电极靠近一导电基底表面至间距与超微盘电极的直径相当时，针尖电极上的电化学反应产物能够有效地扩散至基底表面，并可能在其上发生电极反应使之复原为原反应物或生成其他有关物种，从而增大针尖电极上的电化学反应电流（对应于反应物种浓度）或影响该电极过程．本文将报道扫描电化学显微技术中的这一正反馈作用对Ａｕ／ＨＣｌ体系的电化学振荡行为的影响．Ａｕ电极的阳极过程一般认为由下列两步构成：快速电极反应（１）均相化学反应（２）氧化膜的形成和溶解是发生振荡的一个起因，其中Ｃｌ￣－浓度的变化是一关键因素．当发生振荡着的Ａｕ电极靠近Ｐｔ基底至一定间距时，慢速的歧化反应（反应（２））产物扩散至Ｐｔ上，导致产生大量的Ｃｌ￣－并进一步反向扩散至Ａｕ电极上，使Ａｕ氧化膜溶解导致反应（１）速度迅速增大，表现出电流显著上升，并构成新的振荡强度和时序（振荡幅度显著增加且周期有所增大）．这一反馈作用引起的Ｃｌ￣－离子浓度的增大也可诱导振荡的发生，使该体系在处于未发生正常振荡的电位下提前出现振荡．实验结果表明，对于受扩散过程控制的电化学振荡体系，可利用电极基底的正反馈作用影响其振荡过程，以至诱导振荡的发生．
When a tip electrode is close to the surface of a conductive substrate and the pitch is equal to the diameter of the electrode, the electrochemical reaction product on the tip electrode can effectively diffuse to the surface of the substrate and an electrode reaction may take place thereon to restore the original Reactants or generate other related species, thereby increasing the electrochemical reaction current (corresponding to the concentration of reactive species) at the tip electrode or affecting the electrode process. This article reports the effect of this positive feedback in scanning electrochemical microscopy on the electrochemical oscillatory behavior of the Au / HCl system. Au electrode anode process is generally considered to be composed of the following two steps: Rapid Electrode Reaction (1) homogeneous chemical reaction (2) the formation and dissolution of oxide film is a cause of oscillation, in which Cl ~ - concentration changes is a key factor . The slow disproportionation reaction (reaction (2)) diffuses to Pt when the oscillating Au electrode is close to the Pt substrate, resulting in a large amount of Cl- and further back-diffusion to the Au electrode The dissolution of the Au oxide film causes the reaction (1) to rapidly increase in velocity, showing a significant increase in current and resulting in new oscillation intensities and timing (a significant increase in oscillation amplitude and an increase in the period). The increase in the Cl ~- ion concentration caused by this feedback action can also induce the oscillation to take place, allowing the system to oscillate prematurely at a potential at which normal oscillations have not occurred. The experimental results show that for the electrochemical oscillation system controlled by the diffusion process, the positive feedback of the electrode substrate can be used to influence the oscillation process and induce the oscillation.