【摘要】 制备了多壁碳纳米管修饰乙炔炭黑微电极并研究了Sn(Ⅱ)在该电极上的阳极溶出伏安行为。实验发现,在1mol/L HCl溶液中,Sn(Ⅱ)于-1000mV(vs.SCE)处被吸附还原,富集在该修饰电极表面。从-1000mV以100mV/s的速率正向扫描至0mV,锡在约-610mV处出现一灵敏的阳极溶出峰,峰电流比未修饰电极增大约9倍。采用二阶导数线性扫描伏安法进行定量分析,峰电流与Sn(Ⅱ)的浓度在4.0×10-8～1.0×10-5mol/L范围内分二段呈良好的线性关系,检出限(S/N=3)为2.0×10-8mol/L(富集时间90s)。方法用于生铁和合金钢样品中锡的测定,结果与电感耦合等离子体原子发射光谱法的结果一致。更多还原

【Abstract】 A multi-walled carbon nanotubes modified acetylene carbon black microelectrode was prepared and the anodic stripping voltammetric behavior of tin on the modified electrode was investigated. As shown by experimental results,Sn(Ⅱ) is accumulated and reduced on the surface of the modified electrode at-1 000 mV (vs. SCE) in 1 mol/L HCI solution. When positive scanning ran from-1 000 mV to 0 mV at a scanning rate of 100 mV/s,a sensitive anodic stripping peak appeared at-610 mV. The sensitivity of the modified electrode in the determination of Sn (Ⅱ) increased about nine-fold. By means of the second derivative linear sweep technique,the stripping peak current showed a good linear relationship with the concentration of Sn (Ⅱ) in the range of 4.0×10-8-1.0×10-5 mol/L and the detection limit was 2.0×10-8 mol/L (S/N=3) for 90 s of accumulation. This method was applied to the determination of tin in pig iron and alloy steel samples.The results agreed well with those obtained by ICP-AES.更多还原