Nine non-noble-metal catalysts (NNMCs) from five different laboratories were investigated for the catalysis of O(2) electroreduction in an acidic medium. The catalyst precursors were synthesized by wet impregnation, planetary ball milling, a foaming-agent technique, or a templating method. All catalyst precursors were subjected to one or more heat treatments at 700-1050 degrees C in an inert or reactive atmosphere. These catalysts underwent an identical set of electrochemical characterizations, including rotating-disk-electrode and polymer-electrolyte membrane fuel cell (PEMFC) tests and voltammetry under N(2). Ex situ characterization was comprised of X-ray photoelectron spectroscopy, neutron activation analysis, scanning electron microscopy, and N(2) adsorption and its analysis with an advanced model for carbonaceous powders. In PEMFC, several NNMCs display mass activities of 10-20 A g(-1) at 0.8 V versus a reversible hydrogen electrode, and one shows 80 A g(-1). The latter value corresponds to a volumetric activity of 19 A cm(-3) under reference conditions and represents one-seventh of the target defined by the U.S. Department of Energy for 2010 (130 A cm(-3)). The activity of all NNMCs is mainly governed by the microporous surface area, and active sites seem to be hosted in pore sizes of 5-15 A. The nitrogen and metal (iron or cobalt) seem to be present in sufficient amounts in the NNMCs and do not limit activity. The paper discusses probable directions for synthesizing more active NNMCs. This could be achieved through multiple pyrolysis steps, ball-milling steps, and control of the powder morphology by the addition of foaming agents and/or sulfur.

Highly porous N-doped activated carbon monoliths (ACMs) are fabricated by carbonization and physical activation of mesoporous polyacrylonitrile (PAN) monoliths in the presence of CO(2). The monoliths exhibit exceptionally high CO(2) uptake; 5.14 mmol g(-1) at ambient pressure and temperature and 11.51 mmol g(-1) at ambient pressure and 273 K.

Mesoporous polyacrylonitrile (PAN) monolith has been fabricated by a template-free approach using the unique affinity of PAN towards a water/dimethyl sulfoxide (DMSO) mixture. A newly developed Thermally Induced Phase Separation Technique (TIPS) has been used to obtain the polymer monoliths and their microstructures have been controlled by optimizing the concentration and cooling temperature.

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The amount of platinum in the catalyst for the electrodes of polymer electrolyte fuel cells must be minimized to widely substitute this new energy system for conventional ones. In this study, a platinum-free catalyst for the cathodic oxygen reduction was formed from a natural organic compound, catalase. We carbonized catalase to produce a catalyst active in the superacidic atmosphere of the polymer electrolyte. Nitrogen adsorption onto the carbonized material revealed that the material had highly developed internal nanospaces, which were essential for exposing active sites to oxygen reduction on the pore surface. The carbonized material was also characterized by X-ray photoelectron spectroscopy, X-ray diffraction, transmission electron microscopy, and Mössbauer spectroscopy. The activity for oxygen reduction was evaluated using rotating disk electrodes, forming a catalyst layer from the carbonized material and the polymer electrolyte on the electrode surface and immersing the layer in oxygen-saturated perchloric acid. The activity increased with the increase in the specific surface area and possibly the increase in the activity of the respective active sites. A preliminary fuel cell test using the material in the cathode confirmed the electricity generation, although the performance was inferior to a Pt-based fuel cell.