Metal oxide nanofibers

The electrical and mechanical stability of metal oxide nanofibers fabricated on electrode substrates is one of the most important issues [42]. In order to obtain superior mechanical strength between Ti02 fiber mats and a substrate, a thermocompression step was introduced prior to the calcination step in the creation of inorganic precursor/polymer composite nanofibers. For example, as-spun Ti02 precursor/PVAc composite fibers were hot pressed at 120 °C for 10 min. 

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Table 2.3 Characteristics of several metal oxide nanofiber-based conductometric gas sensors...

TABLE 8.3 A selection of metal oxide nanofibers reported in the recent electrospinning literature ... 

Catalysts play an important role when they are combined with metal oxide nanofibers with modification and optimization of the material properties. Such catalysts can greatly reduce the overpotential of the electrochemical reaction and accelerate the reaction rate by lowering the activation energy. Metal and metal oxide nanoparticle catalysts have been functionalized on the surface or embedded within metal oxide nanofibers. For the optimization of the catalytic effect, the loading amoimt, size, and location are important parameters. As one example, Pd-loaded Sn02 nanofibers were simply... 

In the literature, hybrid solar cells with the active layer composed of CdS-coated cellulose acetate fibers and P3HT were reported by Cortina et al. [81]. Wu et al. reported the enhanced performance of hybrid solar cells made of ZnO nanoflbers by modifying the surface of fibers with CdS [82], To apply more electrospun nanofibers and QDs to hybrid solar cells, the generation of effective interface of electrospun metal oxide nanofibers with QDs before blending with polymer is necessary. Dispersion of QDs in electrospun fibers may be also an alternative way for hybrid applications. 

Metal oxides deposited carbon nanofiber Fig. 7.6 Schematic illustration for fabricating hybrid carbon/metal oxides nanofiber... 

Especially for supercapacitor electrode, combination of metal oxides with highly conductive carbon nanofiber has been studied intensively. Figure 7.6 shows the illustration for preparing hybrid carbon/metal oxides nanofiber. In these composite electrodes, the carbon substrate acts as a highly porous conducting network that enables a good access of ions and electrons to the metal oxides. 

Most of the electrospinning procedures that yield metal oxide nanofibers involve pyrolysis of a guide polymer as a final processing step. Bender and co-workers demonstrated, using diffuse reflectance Fourier transform infrared spectroscopy (DRIFTS), that CO2 is sequestered in electrospun metal oxide nanofibers upon... 

Bender ET, Katta P, Lotus A, Park SJ, Chase GG, Ramsier RD (2006) Identification of CO2 sequestered in electrospun metal oxide nanofibers. Chem Phys Lett 423(4-6) 302-305. doi 10.1016/j.cplett.2006.03.092... 

As wc know, carbon nanofibers have been widely used in various areas, such as in electronic components, as polymer additives, for gas storage, and as catalyst support [94]. Via the decomposition of hydrocarbons or carbon monoxide over Ni, Co or Fe catalysts, a large quantity of carbon fibers can be produced. Moreover, these carbon fibers with different sizes and shapes, such as straight, bent, thin and helical, etc., could be synthesized by controlling the reaction conditions [95-99]. With carbon nanofibers as template, Ueda and co-workers prepared a number of single and binary transition metal oxide nanofibers and/or nanotubes, including LaMnOs and LaFeOs nanofibers and nanotubes [99-102]. 

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