Energy composite electrodes

The addition of an ionic conductive phase, such as GDC, also promotes the elec-trocatalytic activity of an MIEC cathode. Hwang et al. [108] studied the electrochemical activity of LSCF6428/GDC composites for the 02 reduction and found that the activation energy decreased from 142 kJmol-1 for the pure LSCF electrode to 122 kJmol1 for the LSCF/GDC composite electrodes. Thus, the promotion effect of the GDC is most effective at low-operation temperatures (Figure 3.12). This is due to the high ionic conductivity of the GDC phase at reduced temperatures. 

Figure 2. Energy band diagram of the CdSe-SrTiOs composite electrodes (A refers to CdSe and B to SrTiO,)...

Ahn S, Tatarchuk BJ (1990) Composite electrode structures for fuel cell applications. Proceedings of the 25th intersociety energy conversion engineering conference 3 287-92... 

Figure 6.22. Nyquist plots for (A) a composite electrode at -450 mV vs. SCE and (B) a Prototech electrode at 450 mV vs. SCE [22], (Reproduced from Ahn S, Tatarchuk BJ, Composite electrode structures for fuel cell apphcations. Proceedings of the 25th Intersociety Energy Conversion Engineering Conference, 1990 3 287-92, with permission from the American Institute of Chemical Engineers.)...

This is an area of much practical importance for research and development in electrolyzer technology more work is currently required for elucidation of the behavior of high-area porous and composite electrode materials with regard especially to the values of Tafel slope and conditions under which low b values can be achieved for H2, O2, and CI2 evolution reactions, thus minimizing activation overpotential energy losses in high current-density operations. 

NGU 13] NGUYEN B.P.N., Kumar N.A., Gaubicher J., et al, Nanosilicon-based thick negative composite electrodes for lithium batteries with graphene as conductive additive . Advanced Energy Materials, vol. 3, pp. 1351—1357, 2013. 

Oyama, N., Tktsuma, T., Sato, T., Sotomura, X, 1995. Dimercaptan-polyaniline composite electrodes for lithium batteries with high energy density. Nature 373,598-600. 

Lee, H.,Yoo, J.K., Park, J.H., Kim, J.H., Kang, K., Jung,Y.S., 2012. A Stretchable polymer-carbon nanotube composite electrode for flexible lithium-ion batteries porosity engineering by controlled phase separation. Adv. Energy Mater. 2,976-982. 

The ESs mentioned above consist of two electrodes with the same type of capacitive materials made from either EDL capacitive materials or pseudocapacitive materials (symmetrical configuration). In order to further increase the operating potential window, energy, and power density, a new type of ES has been developed, which is known as hybrid capacitors. With extensive achievements in this area, various types of hybrid ESs have been developed. Generally, hybrid capacitors utilize both the EDL capacitance and faradaic reaction to store charges. The hybrid capacitors reviewed in this book include (1) ESs based on composite electrodes made from both EDL capacitive materials and pseudocapacitive materials (2) asymmetric ESs with one EDL electrode and another pseudocapacitive or battery-type electrode and (3) asymmetric ESs with one pseudocapacitive electrode and another rechargeable battery-type electrode. 

Patil et al. synthesized PPy/polyacrylic acid (PAA)Zsilver (Ag) composite electrodes by chemical polymerization via a simple and cost-effective dip-coating technique for supercapacitor application [75]. The higher SC and specific energy of the PPY/PAA/Ag composite of 226 F/g and 17.45... 

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