Membrane-electrode assembly representation

Figure 9.23 Schematic representation of the various electrochemical and chemical reactions occurring in a membrane electrode assembly and the concentration gradients of O2, H2, and Pt ions. The location where the local O2 molar flux equals one-half of the local H2 molar flux is marked by 5pt. (Reproduced with permission from Zhang J et al. [2007a].)...

Figure 15.2 Schematic representation of different electrochemical cell types used in studies of electrocatalytic reactions (a) proton exchange membrane single cell, comprising a membrane electrode assembly (b) electrochemical cell with a gas diffusion electrode (c) electrochemical cell with a thin-layer working electrode (d) electrochemical cell with a model nonporous electrode. CE, counter-electrode RE, reference electrode WE, working electrode.

Figure 3.15. Schematic representation of the correlation between fuel cell impedance and polarization curve. (Modified from [23], with kind permission from Springer Science+Business Media Journal of Applied Electrochemistry, Characterization of membrane electrode assemblies in polymer electrolyte fuel cells using a.c. impedance spectroscopy, 32(8), 2002, 859-63, Wagner N. Figure 4.)...

Figure 12.1 Schematic representation of a membrane-electrode assembly of a PEMFC. Platinnm particles and carbon agglomerates are colored in black and dark gray, respectively.

Figure 3.1. Schematic representation of a PEM fuel cell single membrane electrode assembly (MEA) with electrochemical reactions occurring at catalyst particles (dark circles).

This chapter presents the simulation of a button cell data reported by Liu et al. [38]. The model parameters derived here are further used in the performance analysis presented in the later chapters. A schematic representation of button cell is given in Fig. 6.1. The configuration is basically a concentric cylindrical assembly intercepted by the membrane electrode assembly (MEA). The fuel and air inlet are through the inner cylindrical pipe, which reaches above the anode and cathode. The product gas outlet is through the concentric space between the inner and outer cylinder. 

Figure 9.8 (a) Schematic representation of oxidized to H. (b) Structure of the the structure and reactivity of the bio-inspired membrane-electrode assembly used for the H2-evolving nickel catalyst grafted on a carbon electrocatalytic characterization of the nanotube [51]. Electrons are exchanged Ni-functionalized CNTs under conditions... 

The conversion of chemical energy to electrical energy in a PEM fuel cell occurs through a direct electrochemical reaction. It takes place silently without combustion. The key part of a PEM fuel cell, which is known as a membrane electrode assembly (MEA), consists of a polymer electrolyte in contact with an anode and a cathode on either side. To limction, die membrane must conduct hydrogen ions (protons) and separate either gas to pass to the other side of the cell. A schematic representation of a PEM fuel cell is shown in Figure 1.5. 

Fig. 39.1a shows a schematic representation of the HUP/C supercapacitor a pure solid electrolyte membrane separates two composite electrodes composed of a mixture of highly polarizable electrode particles and electrolyte crystallites. Current collectors and plastic encapsulation complete the component. The manufacturing process involves (i) synthesis of electrolyte powder for the pure electrolyte membrane (ii) synthesis of the intimate mixture of composite electrode parts (iii) pressure performing of the membrane (iv) assembly of the two composite electrodes and the... 

Figure 5.26 Schematic representation of a copper-selective 2,2 -thiobisethyl acetoacetate-w-octa-decylmercaptan SAM. Reprinted with permission from I. Rubinstein, S. Steinberg, Y. Tor, A. Shanzer and J. Sagiv, Ionic recognition and selective response in self-assembling monolayer membranes on electrodes, Nature (London), 332, 426-429 (1988). Copyright (1988) Macmillan Magazines Limited...

Girishkumar and co-workers [190] reported a preparation procedure for the MEA using CNTs as a support for PEM fuel cells. A schematic representation of their CNT-based proton exchange membrane assembly for a H2/O2 based fuel cell is shown in Figure 14.25. In their experiment, an electrophoretic deposition technique was employed to cast films of CNTs on carbon fiber paper. Two carbon paper electrodes are kept 5 mm apart in a cell containing a CNT suspension in... 

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