| Electrochemical oscillations are spatiotemporal ordered phenomena in electrochemical systems where are located far from the equilibrium. In recent years, the experimental and theoretical studies of electrochemical oscillations have been beginning using various methods. Oscillations could be observed in many electrochemical systems and the investigation of oscillations is now becoming a new branch of modern electrochemistry. Complex oscillations about anodic dissolution of copper in concentrated phosphoric acid solutions have been observed. There are many reports on the study of CU/H3PO4 system. We can know further mechanism that abundant oscillations of the anodic dissolution of copper arise from various conditions near anode by studying the influence of additives in the above system. In this paper, the roles of various additives on anodic dissolution of copper in phosphoric acid were studied. The rules of influence were given briefly according to previous mechanism and the characteristics of additives.Through cyclic voltammetry and potentiostatical experiment, the effects of scan-rate, temperature, the concentrations of additives and potential on the oscillations are studied. These additives include Cr(VI), hydrogen peroxide , aminoacatic acid , glucose , Imidazole and polyglycol .We find the oscillations are the result of the forming and breaking of film coupling with the mass transport, particularly the concentrations of H+/OH- near anode. We also find a direct relationship between potential at the begin of oscillations , the features and various additives , concentrations. An experimental proof that the complex oscillations are the result of CU2O is given. Expect damped oscillations , periodic oscillations, quasiperiodic oscillations and mixed oscillations, we also find some new complex oscillations.
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