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Porous cathodes of NiO(Li), Co-doped LiFeO2, and LiCoO2 for the molten carbonate fuel cell (MCFC) were examined in a comparative study using electrochemical impedance spectroscopy at temperatures of 923,973, and 1023 K. Using this technique the contributions of charge transfer and diffusion to the impedance could be separated. The impedance results as a function ol gas composition were compared with theoretical predictions using the thin-film model leading to the conclusion that the most predominant diffusing species in porous MCFC electrodes are molecular oxygen and carbon dioxide. The reaction mechanism is probably the same for all three cathodes involving either the reduction of peroxycarbonate or the reduction of dissociated oxygen. The remaining difference in gas dependencies can then be explained by assuming a low coverage of oxide ions on LiFeO2 while NiO(Li) and LiCoO~ have intermediate coverage by oxide ions. From the temperature dependence of the impedance an estimate may be given of the activation energies of the polarization processes.

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This paper reports on the refinement of constructive conflict methodology (CCM) combining Q methodology and stakeholder dialogue workshops for gas futures for the Netherlands. Since the end of the 1950s, natural gas exploration and exploitation has been a major focus of the Dutch energy policy. Discussions about the future of energy in the Netherlands tend to focus either on pro-gas or pro-renewable energy. Using Q methodology we have constructed more nuanced perspectives on the future of energy in the Netherlands. We used these perspectives in a stakeholder dialogue, in which the participants further detailed the perspectives and discussed future policy options. Analysis of the outcomes of this process teaches us that the Netherlands remain gas-focused, that renewable energy sources are as much a dogma as nuclear power was in the 1960s, and that the prospect of an austere future is a non-debatable issue. From a methodological perspective it can be concluded that the refined methodology contributed to diversity in views, opened up the dominant discourse and led to learning among participating stakeholders.

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Both the hydroxide and the carbonate melt are proposed and tested by researchers trying to develop a DCFC (Direct Carbon Fuel Cell). It is well known that the hydroxide melt is not stable due to the carbon dioxide formed in the fuel cell reaction. The hydroxide ion reacts with CO2 to form carbonate ions and water. From this reaction it is clear that in either approach the melt is a mixture of carbonate and hydroxide depending on the partial pressures of water and CO2 above the melt. Therefore a good insight in the equilibria present in the melts is essential for understanding and optimizing the DCFC. Following the method introduced by Smith and Missen a complete and independent set of equilibria describing the chemical equilibrium in the melt can be obtained using linear algebra. Using the modification proposed by Coleman and White also electrochemical equilibria are included. This is done for the cathode as well as the anode environment of a DCFC with a carbonate and/or hydroxide melt as electrolyte. Hereby the open cell voltage for a DCFC including the Boudouard equilibrium could be calculated. It was found that the OCV increases as a function of temperature even more rapidly than the standard potential for the electrochemical oxidation of carbon to CO, which also has a positive slope due to a positive entropy change of the overall reaction. This extra high OCV is an additional argument for developing the DCFC in particular a DCFC at high temperatures in which predominantly CO is produced. Since CO can easily be shifted to hydrogen in a water gas shift reaction with steam, coproduction of hydrogen and power can be obtained using carbon and high temperature heat as energy inputs.