Anode catalyses improved

Reddington et al. (66) reported the synthesis and screening of a 645-member discrete materials library L9 as a source of catalysts for the anode catalysis of direct methanol fuel cells (DMFCs), with the relevant goal of improving their properties as fuel cells for vehicles and other applications. The anode oxidation in DMFCs is reported in equation 1 (Fig. 11.12). At the time of the publication, state-of-the-art anode catalysts were either binary Pt-Ru alloys (67) or ternary Pt-Ru-Os alloys (68). A systematic exploration of ternary or higher order alloys as anode catalysts for DMFCs was not available, and predictive models to orient the efforts were also lacking. 

Improving bioanodes performances and efficiencies will be the most important task in future studies of enzymatic anodic catalysis. Based on research carried out in the past few years, trends for improving performance rely on better electron transport methods and higher enzyme loading. Electron transport could be improved, for example, by developing novel mediators and redox polymers for MET or by controlling orientation of enzymes to improve DET. Enzyme loading techniques could be improved to increase active enzyme concentration per unit of electrode area or volume. 

Catalysis Issues in SOFC Catalytic processes play in important role in the operation of in particular, the SOFC anode and cathode, and the major challenges for the further development of SOFC towards a commercial project are largely related to improving catalytic activity and robustness. The critical technical issues for SOFC are reliability and lifetime, while economic requirements impose low manufacturing and materials costs. 

Figure 3.3.14 Experimental ORR activity of dealloyed Pt-Cu and Pt-Ni core-shell nanoparticle ORR catalysts compared to a pure-Pt nanoparticle catalyst. All three catalyst particles are supported on a high surface area carbon material indicated by the suffix 1C. The shift of the j-E curve of the core-shell catalysts indicates the onset of oxygen reduction catalysis at a more anodic electrode potential (equivalent to a lower overpotential) and hence represents improved ORR reactivity compared to pure Pt.

The slow kinetics of the cathode oxygen reduction reaction (ORR) plays the key role in limiting PEMFC performance when pristine hydrogen is used as the fuel. Therefore, improving the catalytic activity for the ORR has drawn most of the research attention in catalysis studies. Cathode contamination has attracted less attention compared with anode contamination, and only a limited number of papers have been published. Pollutants in air include NOx (NO2 and NO), SOx (SO2 and... 

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