碳糊电极吸附伏安法测定痕量钒  

Determination of Trace Amount of Vanadium by Adsorptive Voltammetry at a Carbon Paste Electrode

作　　者：毛勋[1] 黎拒难[1] 高朋[1] 严志红[1] 

机构地区：[1]湘潭大学化学学院,湖南湘潭411105

出　　处：《分析科学学报》2004年第6期577-579,共3页Journal of Analytical Science

基　　金：中科院长春应化所电分析化学国家重点实验室基金(SKLEAC2003 5);湖南省教育厅基金(01C113)

摘　　要：研究了钒 荧光镓(LMG)络合物在碳糊电极上的吸附伏安行为,发现其在+0.81V(vs.SCE)的阳极二次导数峰电流与钒(V)的浓度在一定范围内呈线性关系。在pH=4.3的0.26mol/L的HAc NH4Ac缓冲溶液中,于+0.4V富集,从+0.4至+1.4V以300mV/s线性扫描,方法线性范围为4.0×10-9～1.0×10-7mol/L(5.0×10-7mol/LLMG)和1.0×10-7～1.2×10-6mol/L(2.0×10-6mol/LLMG),检出限为1.0×10-9mol/L(S/N=3)。该法用于煤飞灰,粉煤灰和水样中钒的测定,结果满意。A new method was presented for the determination of vanadium based on anodic adsorptive stripping of the vanadium (Ⅴ)-lumogallion (LMG) complex at a carbon paste electrode (CPE). The complex can be adsorbed on the surface of the CPE and an anodic peak at 0.81 V (vs.SCE) can be observed with linear-scanning from 0.4 V to 1.4 V. Optimal analytical conditions were found to be :(0.26) mol/L HAc-NH-4Ac (pH=4.3), 120 s for accumulation at 0.4 V and a 300 mV/s scan rate. The linear range is 4.0×10+(-9)～1.0×10+(-7)mol/L(5.0×10+(-7)mol/L LMG) and 1.0×10+(-7)～1.2×10+(-6)mol/L(2.0×10+(-6)mol/L LMG). The detection limit is as low as 1.0×10+(-9)mol/L (S/N=3). The proposed method has been applied successfully to the determination of vanadium in flying coal-ash, fly-ash and tap water.

关 键 词：钒 荧光镓 碳糊电极 吸附伏安法 

分 类 号：O657.15[理学—分析化学] O614.511[理学—化学]