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Acetobacter aceti and Gluconobacter roseus, which are known to be responsible for the spoilage of wine, are used for current generation in batch-type microbial biofuel cells and it has been shown for the first time that these two microorganisms do not require mediators for the transfer of electrons to the anode. Three biofuel cells were constructed with two cells containing the pure cultures of each of the microorganisms as the biocatalyst (A-MFC, G-MFC) and the third cell was constructed with the mixed culture of these two microorganisms as the biocatalyst (AG-MFC). The performance of the biofuel cells was evaluated in terms of open circuit voltage (OCV), fuel consumption rate, internal resistance, power output, and coulombic efficiency. The mixed culture cell (AG-MFC) exhibits a better overall performance compared to the other cells.

A soft route for the preparation of catalytically active multilayers of Pt films free from poisoning effects is reported. The SAMs (self-assembled monolayers) were initially formed on the gold substrates and they act as nucleating centers initiating the formation of multilayers of Pt on gold substrates. The nanoscale to mesoscale structures of Pt thus prepared were characterized by SEM and XPS. The SAM-based Pt structures exhibited well-defined hydrogen adsorption, desorption regions associated with very high charge indicating high surface area Pt. The electrocatalytic activity of the multilayers of Pt was characterized by methanol oxidation and a comparison was made with two commercial Pt catalyst preparations.

Hexacyanoferrate modification of gold electrode has been achieved by immobilizing the species in a self-assembled monolayer of 3,3‘-thiodipropionic acid anchored to the gold surface. The surface coverage of hexacyanoferrate is estimated from the voltammetric data point to be about one monolayer, and the modified electrode exhibits excellent surface redox behavior. Further, it shows good electrocatalytic influence on the oxidation of hydrazine and ascorbic acid.

A gold electrode surface has been modified with a monolayer of 3,3'-thiodipropionic acid (TPA) by self-assembly. The pH-sensitive TPA monolayer is further derivatized to form a monolayer of nickel hexacyanoferrate. This electrode shows molecular discrimination between potassium and sodium ions and exhibits a near-Nernstian response, with a slope of 55 mV/decade to potassium ions in the range from 10 -2 to 1 M.