Graphite-Composite Electrodes Bulk-Modified with (BiO)_2CO_3 and Bi_2O_3 Plates-Like Nanostructures for Trace Metal Determination by Anodic Stripping Voltammetry

摘要

We describe the preparation of bismutite ((BiO)_2CO_3) and bismuth-oxide (Bi_2O_3) plates-like nanostructures and their incorporation within graphite-composite electrodes for the determination of trace metals by anodic-stripping-voltammetry. The bismuth nanostructures were produced under microwave-hydrothermal conditions followed by thermal conversion of as-prepared precursor and characterized by X-ray diffraction, Fourier-transformed infrared and field-emission scanning-electron-microscopy. Graphite-composite electrodes bulk-modified with Bi_2O_3 nanostructures provided higher sensitivity and lower detection limits for determinations of cadmium, lead and zinc (0.26; 0.52; and 2.23μgL-1, respectively) employing short deposition time (60s). The results indicate that the modification of graphite-composite electrodes with Bi_2O_3 nanostructures improved analytical characteristics of electrochemical sensors for trace-metal determinations.