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The lack of stable and economic supporting materials at high voltages hampers the development of electrocatalysts for oxygen evolution reaction (OER), which is the major source of energy loss in water splitting to produce hydrogen. In this work, we developed systematic methods to evaluate candidate compounds that can potentially replace traditional carbon support for OER catalysts. Stability, economic and conductivity criteria of the oxide support materials were studied and discussed. A nano-sized antimony-doped tin oxide was fabricated to support RuO2, which was shown to provide the highest stability and activity of OER in 0.5 M H2SO4 up to 2.5 VRHE and up to 55°C. [ABSTRACT FROM AUTHOR]

The article discusses aspects of general discussions on the many faces of carbon in electrochemistry. Topics include discussions of various scientists and professors, including George Zheng Chen on electrode capacitance for different carbons, Héctor Abruña on electrochromic applications of conducting polymers and Kathrine Holt on pH sensitivity of functional groups on graphene.

Acidic or alkaline direct ethanol fuel cells (DEFCs) can be a sustainable alternative for power generation if they are fuelled with bioethanol. However, in order to keep the fuel cheap, ethanol has to be exempted fromtax on spirits by denaturing. In this investigation the potential denaturing agents fusel oil, tert-butyl ethyl ether, and Bitrex were tested with regard to their compatibility with fuel cells. Experiments were carried out both in sulphuric acid and potassium hydroxide solution. Beside, basic electrochemical tests, differential electrochemicalmass spectrometry (DEMS) and fuel cell tests were conducted. It was found that fusel oil is not suitable as denaturing agent for DEFC. However, tert-butyl ethyl ether does not seem to hinder the ethanol conversion as much. Finally, a mixture of tert-butyl ethyl ether and Bitrex can be proposed as promising candidate as denaturing agent for use in acidic and alkaline DEFC. [ABSTRACT FROM AUTHOR]

Abstract: A vanadium/oxygen fuel cell with an active area of 280 cm2 has been developed. The cell consisted of two membranes with two half-cells and an intermediate chamber. The maximum achieved power density was 23 mW cm−2 at 0.56 V with lambda air = 3 and a 1.6 M V2+ solution at room temperature. The average discharge power density was 19.6 mW cm−2 at a constant current density of 40 mA cm−2 with an average voltage efficiency of 33%. The fuel based energy density was 18.2% of the theoretical value with 11.8 Wh L−1. In comparison with a similarly constructed 50 cm2 cell, both achieved similar performance levels. An analysis using the half-cell potential profiles and by means of impedance spectroscopy revealed that, as for the 50 cm2 cell, the low rate of oxygen reduction reaction significantly affected the performance of the cell. Thus gives potential for the optimization of the cathode reaction and a reduction in the ohmic resistances potential for higher power densities. [Copyright &y& Elsevier]