ZnO nanotubes were prepared via electrospinning the Zn ( AC ) 2-polyacrylonitrile-polyvinylpyrrolidone ( PAN-PVP) precursor, followed by thermal decomposition of the above polymers from the precursor fibers. SEM and XRD characterization confirmed that the as-prepared ZnO nanofibers presented the hollow nanotube form, which was composed of ZnO nanoparticles with the size of about 40 nm in wurtzite crystal structure. By mixing with graphene, the obtained ZnO-graphene composite modified glassy carbon electrode ( ZnO-RGO/GCE ) was successfully constructed by dip-coating, which was used for the determination of Pb2+in water. With the sensitive response of the ZnO-RGO/GC electrode to Pb2+in solution was demonstrated by square wave stripping voltammetry, the response pctential was at -0. 4V. Under the optimized conditions, a good linear relationship between peak current and Pb2+ concentration was obtained in the range of 2. 4×10-9-4. 8×10-7 mol/L (R=0. 9970) by 10 min preconcentration at -1. 0 V in 0. 1 mol/L HAc-NaAc buffer solution (pH=4. 6). The detection limit was 4. 8×10-10 mol/L (S/N>3). The ZnO-RGO/GC electrode had good stability. The practical analytical application of the ZnO-RGO modified electrode was assessed by the measurement of the actual water sample and the result was consistent with that obtained by ICP-MS.%以聚乙烯吡咯烷酮(PVP)、聚丙烯腈(PAN)和醋酸锌(Zn(Ac)2)为纺丝前驱液,利用静电纺丝技术制备Zn( Ac)2-PAN-PVP复合纳米纤维原丝,经高温煅烧得到ZnO纳米纤维。 X-射线衍射证明ZnO呈纤锌矿结构。扫描电子显微镜( SEM)显示,ZnO纳米纤维呈中空圆管状。将该ZnO纳米管与石墨烯( RGO)按一定比例混合,采用滴涂法制备ZnO-RGO/GC电极,并用于水体中重金属Pb2+的检测。方波溶出伏安分析表明,此修饰电极对重金属Pb2+有灵敏的响应,响应电位约为-0.4 V。在0.1 mol/L HAc-NaAc (pH=4.6)缓冲溶液中,-1.0 V电位下富集10 min, ZnO-RGO/GC电极对Pb2+检测的线性范围为2.4×10-9~4.8×10-7 mol/L,检出限达到4.8×10-10 mol/L(S/N>3)。此电极容易制作,稳定性好,在用于检测实际水体中Pb2+时,其结果与电感耦合等离子体-质谱法( ICP-MS)测试值一致。
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