An amperometric microsensor for the determination of H2S in aquatic environments

摘要: A new amperometric microsensor for detection of dissolved H2S in aquatic environments was developed. The design the is based on same principle as Clark-type oxygen microsensor. sensor equipped with a glass-coated platinum working electrode and guard positioned an outer glass casing (tip diameter 20−100 μm). Both were polarized at fixed value range from +85 to + 150 mV respect counter electrode. sealed thin silicone membrane filled buffered electrolyte solution containing ferricyanide (K3[Fe(CN)6]) redox mediator. Hydrogen sulfide penetrates oxidized by K3[Fe(CN)6], resulting formation elemental sulfur ferrocyanide (K4[Fe(CN)6]). latter electrochemically reoxidized exposed end electrode, thereby creating current that directly proportional concentration...