| Electrochemiluminescence（ECL） matrixed the electrochemistry with chemiluminescence and was a kind of electrochemistry-induced in-situ spectrum behavior. It involved the generation of highly-energetic species at the electrode surface that then emited light via electron transfer reactions. Persulfate(S2O82-) was an interesting ECL reagent. Meanwhile, persulfate itself played a role of luminophore that produced SO4?- at the electrochemical reduction potential of-0.6 V and further reacted in aqueous solution to form light-emitting species of singlet oxygen that emit light over the potential range of-1.4-1.8 V. Furthermore, the persulfate acting as the oxidant was extensively used in the chemical industry for pollutant degradation. The degradation usually happened upon the intermediate oxidation of radical anions SO4?-assistant, by which the chemical unsaturated bond broke to cause the compounds degradation. Thus, the activation strategy of radical anions SO4?- and its related mechanism also were significant for these chemical industry related treatment. Researchs had reported many kinds of means for activating S2O82- to degradate contaminations. However, using S2O82- induced by ECL to degradate contaminations and detect, which was reported few. According to this, the following works were carried out in this thesis.A new type of electrochemistry triggered persulfate oxidation technology was proposed for reactive brilliant blue X-BR dye degradation. The cathode electrochemiluminescence was employed to trigger sulfate radical SO4?-. Based on the synchronous signal of cyclic voltammetry（CV） and luminescence（CL）, the dynamic mechanism research model was built. The structure of degradation products were inferred with the help of ultraviolet spectrum, FTIR spectrum and GC-MS. The results showed that the ECL-induced oxidative degradation exactly happened at the group of anthraquinone and triazine on the dyes molecules. The optimum degradation parameter was at the p H 6.0 with persulfate concentration of 1×10-1 mol·L-1 and reactive brilliant blue X-BR concentration of 1×10-2 mol·L-1, at which the degradation rate reached 66.47%. The degradation reaction obeyed to the first reaction kinetics model, reaction rate constant was 1.01×10-2 min-1.We selected small molecule compound hydroquinone（HQ） as the target pollutant, the advanced oxidation technology of persulfate induced by ECL was used to degradate it. In this work, the way for estabish dynamic mechanism research model was in agreement with the first work. Results showed that under the condition of ECL induction, the current intensity of HQ redox peaks decreased obviously, the content of HQ cut down gradually. The optimum degradation parameter was at the p H 7.5 with the addition of persulfate doses 0.8 m L and HQ concentration of 2×10-2 mol·L-1, at which the degradation ratio reached 63.7%. The degradation reaction included fast and slow steps, both obeyed to the first reaction kinetics model, before and after 180 min, the reaction rate constant were 2.4×10-3 min-1 and 9.5×10-4 min-1, respectively.A layer of nanometer gold（nano-Au） was modified on the electrode surface with the method of one step electrodeposition, and the effects of nano-Au on the ECL of S2O82-was also explored, we observed that nano-Au can increase the ECL intensity and promote the transformation of S2O82- to SO4?-. Based on this phenomenon, we furthure studied the degradation of HQ and the consumption of S2O82- in the way of electrochemistry-induced S2O82-, after nano-Au modified on the electrode surface. The results displayed that nano-Au can accelerate the degradation of HQ in this system. The degradation rate increased with the increasing of the addition dose of S2O82-. Both the degradation of HQ and the consumption of S2O82- conformed to the first reaction kinetics model. The optimum degradation parameter was at the p H 7.5 with the addition of persulfate doses 1.2 m L and HQ concentration of 1×10-2 mol·L-1, at which the degradation ratio reached 96.23%. |
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