Determination Of Heavy Metal Ions On Bismuth Film Modified Electrode

In recent years, with the large-scale development of industrial production and vast industrial waste into the environment constantly, environmental pollution has been becoming a serious problem, especially for heavy metal contaminations. The accumulation period of most heavy metals in soil, plants or animals is very long. Taken by plants, heavy metals may enter the food-chain in significant amounts. Heavy metals whoes characteristic of hiden, irreversible and long-term do great harm to the plants and animals. So the pollution of heavy metal ions to the environment can not be ignored. Therefore, it is important to establish highly sensitive detection method for heavy metal ions. Room temperature ionic liquids (RTILs), nanomaterials and bimuth film have exhibited the unique physical and chemical properties, which can be used in the modified electrodes for determining heavy metal ions.The paper can be summarized as follows:1. A carbon ionic liquid electrode (CILE) was fabricated by using ionic liquid1-hexylpyridinium hexafluorophosphate (HPPFf,), then bismuth film was deposited on CILE by ex-situ deposition. Finally the working electrode Bi/CILE was used for the sensitive anodic stripping voltammetric detection of trace Cd2+.2. A graphene film and bismuth-coated modified glassy carbon electrode (Bi/GR/GCE) was fabricated by directly electroreduction in a graphene oxide colloidal solution and ex-situ depositing bismuth. The anodic stripping voltammetric method was used to determinate trace Hg2+.3. A carbon ionic liquid electrode (CILE) was fabricated by using ionic liquid1-hexylpyridinium hexafluorophosphate (HPPF6), then a graphene film and bismuth-coated modified CILE (Bi/GR/CILE) was fabricated by directly electroreduction in a graphene oxide colloidal solution and ex-situ depositing bismuth. The working electrode Bi/GR/CILE was used for the sensitive anodic stripping voltammetric detection of trace Cd2+and Pb2+.The factors containing supporting electrolyte, pH of solution, accumulation time and deposition potential were investigated. The influence of common metal ions on the determination of heavy metal ions was also investigated. Under the optimal conditions, the fabricated bismuth modified electrodes were successfully used as the working electrode for the detection of metal ions. The differential pulse anodic stripping voltammograms of heavy metal ions on different working electrodes were compared. The proposed methods were successfully applied to the real samples analysis with satisfactory results.