Bismuth microelectrode system with in situ renewable surface for electroanalysis and adsorption studies

A modified scrape method for preparation of nearly single crystalline bismuth microelectrode with the in situ renewable surface and the corresponding measurement system has been worked out, being a promising replacement of the toxic dropping mercury electrode. The cleaved bismuth capillary electrode (BiCCE) surface is renewed in situ by breaking 320 μm long cylinders onto a top of a capillary. This process can be repeated 150 times for the 5 cm long electrode. The AFM data and electrochemical measurements of pyridine adsorption indicate that the cleaved surface consists mainly of the Bi(1 1 1) single crystal plane areas. The very pure in situ renewable surface enables to measure the zero charge potential at the moment of the electrode cleavage. Some examples of electrochemical detection with the BiCCE are shown like trace metal stripping and flow-injection analysis of some ions and organic compounds.