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掺硼金刚石膜(BDD)电极是一种理想的用于电化学分析微量重金属离子的非汞电极,选择合适的BDD电极类型和探索简便的活化BDD电极的方法对提高其电分析检测能力和延长其使用寿命具有重要意义。本研究考察了3种硅基掺硼浓度(B原子浓度分别为2×1020/cm3、8×1020/cm3和27×1020/cm3,简写为BDD-2、BDD-8和BDD-27)的BDD电极经历相同的阴极预处理:在0.5 mol/L H2SO4溶液中,阴极恒电位(-3V vs.饱和甘汞电极)极化5、10、20、30和50 min后,以铁氰化钾/亚铁氰化钾为氧化还原探针,用交流阻抗和循环伏安技术表征了阴极极化后的BDD电极的电化学活性,并用阳极溶出伏安法,通过对一系列已知浓度的铅离子的测量试评估了阴极活化的效果。结果表明,电化学阴极预处理能显著提高3种掺硼浓度的BDD电极的表面活性,但阴极活化效果与BDD的掺硼浓度和阴极预处理时间有关,BDD-27和BDD-8的最佳阴极预处理时间分别为30 min和10 min,BDD-2因表面活性太差并不适合用于电分析。
The boron doped diamond film (BDD) electrode is an ideal non-mercury electrode for the electrochemical analysis of trace heavy metal ions. Choosing a suitable BDD electrode type and exploring a simple and convenient method of activating the BDD electrode enhances the detection capability and prolongation of its electrical analysis Its useful life is of great significance. In this study, the effects of boron concentrations on three kinds of Si substrates (B atoms concentration of 2 × 10 20 / cm 3, 8 × 10 20 / cm 3 and 27 × 10 20 / cm 3, abbreviated as BDD-2, BDD-8 and BDD-27) BDD electrodes were subjected to the same cathodic preconditioning. After the cathodic potentials (-3V vs. saturated calomel electrode) were polarized for 5, 10, 20, 30 and 50 min in 0.5 mol / L H2SO4 solution, / Potassium ferrocyanide is a redox probe. The electrochemical activity of the BDD electrode after cathodic polarization was characterized by AC impedance and cyclic voltammetry. The anodic stripping voltammetry was used to characterize a series of lead Measurement of ions assesses the effect of cathode activation. The results show that the electrochemical cathodic pretreatment can significantly improve the surface activity of three kinds of BDD electrodes doped with boron concentration, but the cathode activation effect is related to the boron concentration of BDD and the time of cathodic pretreatment, the best of BDD-27 and BDD-8 Cathode pretreatment time was 30 min and 10 min, BDD-2 due to poor surface activity and is not suitable for electrical analysis.