Nanoporous materials electrodes

FIGURE 2.56 Typical structure of the IL inside electrified pores of the CE)C-1200 material. Blue C-C bonds, red BMI+, and green PFs. (a) Local structure near a positive surface (+0.5 V), the anionic density is enhanced, (b) A single anion in a nanotube-like pore positively polarized (+0.5 V). (c) Same as (a) but near a negative surface (-0.5 V). (Reprinted by permission from Macmillan Publishers Ltd. Nature Materials Merlet, C. et al. 2012. On the molecular origin of supercapacitance in nanoporous carbon electrodes. 11 306-310, copyright 2012.)... 

Chen, L. Y, Y. Hou, J. L. Kang, A. Hirata, and M. W. Chen. 2014. Asymmetric metal oxide pseudocapacitors advanced by three-dimensional nanoporous metal electrodes. Journal of Materials Chemistry A 2 8448-8455. 

Kang, J. L., A. Hirata, H. J. Qiu et al. 2014. Self-grown oxy-hydroxide nanoporous metal electrode for high-performance supereapacitors. Advanced Materials 26 269-272. 

Gebeyehu, D., et al. 2002. Hybrid solar cells based on dye-sensitized nanoporous Ti02 electrodes and conjugated polymers as hole transport materials. Synth Met 125 279. 

Not only nanometric structures such as tubes or particles are important but also the application of nanoporous materials such as the case of nanoporous gold films [48, 87] (NPG) that could be prepared by selective dissolution of silver form Au/Ag alloys under free corrosion conditions. In this case, stability of the electrode can be increased and biomolecule immobilization could happen inside the mnable pores. Due to their well-defined nanopores, anodized alumina membranes have found many applications, among them, impedimetric immunosensing [63]. 

A question of practical interest is the amount of electrolyte adsorbed into nanostructures and how this depends on various surface and solution parameters. The equilibrium concentration of ions inside porous structures will affect the applications, such as ion exchange resins and membranes, containment of nuclear wastes [67], and battery materials [68]. Experimental studies of electrosorption studies on a single planar electrode were reported [69]. Studies on porous structures are difficult, since most structures are ill defined with a wide distribution of pore sizes and surface charges. Only rough estimates of the average number of fixed charges and pore sizes were reported [70-73]. Molecular simulations of nonelectrolyte adsorption into nanopores were widely reported [58]. The confinement effect can lead to abnormalities of lowered critical points and compressed two-phase envelope [74]. 

Particularly promising is the development of nanoporous ceramic semiconductor membranes [692-695], They not only possess all of the advantages of ceramic materials, but they may also be efficient light harvesters having large surface areas which could provide sites for sensitizers [108, 711-714]. Indeed, FeS2 particles, deposited into (and onto) a porous Ti02 electrode, sensitized photoelectron conversion well (Fig. 118) [714]. 

Synthesis and Characterization of Nanoporous Carbon and Its Electrochemical Application to Electrode Material for Supercapacitors... 

This volume contains four chapters. The topics covered are solid state electrochemistry devices and techniques nanoporous carbon and its electrochemical application to electrode materials for supercapacitors the analysis of variance and covariance in electrochemical science and engineering and the last chapter presents the use of graphs in electrochemical reaction networks. 

In order to satisfy the industrial demand, the performance of supercapacitors must be improved and new solutions should be proposed. The development of new materials and new concepts has enabled important breakthroughs during the last years. In this forecast, carbon plays a central role. Due to its low cost, versatility of nanotextural and structural properties, high electrical conductivity, it is the main electrode component. Nanoporous carbons are the active electrode material, whereas carbon blacks or nanotubes can be used for improving the conductivity of electrodes or as support of other active materials, e.g., oxides or electrically conducting polymers. 

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