Voltammetry determination of trace manganese with pretreatment glassy carbon electrode by linear sweep voltammetry.

This paper described the determination of trace manganese using linear sweep voltammetry at a pretreatment glassy carbon electrode. The glassy carbon electrode pretreated by electrochemical method in the 0.1 moll(-1) NaOH solution greatly improved the electrode responsibility in the determination of manganese(II). The barrier to the detection of low manganese concentration was overcome by means of autocatalytic effect of manganese oxide deposited on the electrode in advance. Under the optimum experiments condition (0.04 moll(-1) NH(3)-NH(4)Cl buffer solution, pH 9.0), the linear range was 4x10(-8) to 1xl0(-6) moll(-1) Mn(II) for linear sweep voltammetry and 1x10(-9) to 4x10(-8) moll(-1) Mn(II) for convolution voltammetry. The relative standard deviation for 2x10(-8) moll(-1) Mn(II) is 3.4%. The proposed method is simple, rapid, sensitive and selective. It had been applied to the determination of trace manganese in samples with satisfactory results.