Rhodium effects on Pt anode materials in a direct alkaline ethanol fuel cell.

The development of efficient catalysts for ethanol oxidation in alkaline medium requires a synthetic approach that may prevent the surfactant molecules from being adsorbed at the catalytic sites and decreasing the electrochemical performance of the final direct ethanol fuel cell. Toward this goal, the recently reported surfactant-less Bromide Anion Exchange (BAE) method, appears as a promising route to conveniently aim at preparing PtRh alloys dispersed on carbon substrates. The catalysts prepared herein by the BAE method were characterized physicochemically to obtain structural information on the PtRh/C nanomaterials, their morphology (size and shape), and their chemical and surface composition.

Hydrogen and electrical energy co-generation by a cooperative fermentation system comprising Clostridium and microbial fuel cell inoculated with port drainage sediment.

This research work has succeeded in recovering energy from glucose by generating H with the aid of a Clostridium beijerinckii strain and obtaining electrical energy from compounds present in the H fermentation effluent in a microbial fuel cell (MFC) seeded with native port drainage sediment. In the fermentation step, 49.5% of the initial glucose concentration (56 mmol/L) was used to produce 104 mmol/L H; 5, 33, 3, and 1 mmol/L acetate, butyrate, lactate, and ethanol also emerged, respectively.

Hybrid catalyst cascade architecture enhancement for complete ethanol electrochemical oxidation.

MWCNT-COOH, TEMPO-modified linear poly(ethylenimine), and alcohol (ADH) and aldehyde (AldDH) dehydrogenase immobilization on electrode surfaces yields a hybrid, tri-catalytic architecture that can catalyze complete ethanol electro-oxidation. The chromatographic results obtained for the tri-catalytic hybrid electrode system show that ethanol is totally oxidized to CO after 12 h of electrolysis, confirming that organic oxidation catalysts combined with enzymatic catalysts enable collection of up to 12 electrons from ethanol. The Faradaic efficiency lies above 60% for all of the electrode systems investigated herein.

A High Redox Potential Laccase from Pycnoporus sanguineus RP15: Potential Application for Dye Decolorization.

Laccase production by Pycnoporus sanguineus RP15 grown in wheat bran and corncob under solid-state fermentation was optimized by response surface methodology using a Central Composite Rotational Design. A laccase (Lacps1) was purified and characterized and the potential of the pure Lacps1 and the crude culture extract for synthetic dye decolorization was evaluated. At optimal conditions (eight days, 26 °C, 18% (w/w) milled corncob, 0.

High current density PQQ-dependent alcohol and aldehyde dehydrogenase bioanodes.

In this paper, we explore the bioelectrooxidation of ethanol using pyrroloquinoline quinone (PQQ)-dependent alcohol and aldehyde dehydrogenase (ADH and AldDH) enzymes for biofuel cell applications. The bioanode architectures were designed with both direct electron transfer (DET) and mediated electron transfer (MET) mechanisms employing high surface area materials such as multi-walled carbon nanotubes (MWCNTs) and MWCNT-decorated gold nanoparticles, along with different immobilization techniques. Three different polymeric matrices were tested (tetrabutyl ammonium bromide (TBAB)-modified Nafion; octyl-modified linear polyethyleneimine (C8-LPEI); and cellulose) in the DET studies.

The use of PAMAM dendrimers as a platform for laccase immobilization: kinetic characterization of the enzyme.

The kinetic behavior of the enzyme laccase in solution and immobilized onto carbon platforms using poly(amido amine) (PAMAM) dendrimers has been investigated. The results with the immobilized enzymes have demonstrated that almost ten times more enzyme on the carbon support is required for satisfactory kinetic rates to be achieved. Furthermore, the study as a function of the substrate concentration revealed that the kinetic behavior of the enzyme in solution fits the Michaelis-Menten model.