Nanostructure, electrochemical properties

We demonstrated that the morphology of nanostructures, electrochemical, and photoelectrochemical properties in the electrodes modified with nanodusters of Qo can be controlled by applying a strong magnetic field. The present study provides useful information for designing novel nanodevices whose photofunctions can be controlled by a magnetic field. 

Although some nanostructured carbons are able to store reversibly higher amounts of lithium than graphite [2], they generally demonstrate a high hysteresis (see for example Figure 2) that still precludes their use in lithium-ion batteries. In order to improve their electrochemical properties as electrode materials, a current effort is made to better understand the... 

On the other hand, liquid phase deposition (LPD) has been demonstrated as a flexible wet chemical method for preparing metal oxide nanostructured films on electrode surfaces. By the LPD process, electroactive titanium dioxide (Ti02) films were prepared on graphite, glassy carbon and ITO. The electrochemical properties of such LPD Ti02 films were dependent upon the film thickness controlled by the deposition time. The LPD technique was easily combined with other techniques, e.g., seed-mediated growth, which could provide metal/metal oxide composite nanomaterials. Moreover, hybrid nanostructured films were facilely obtained by doping dyes, surfactants and other... 

A relatively high reversible capacity (372mAh/g, i.e., one lithium for six carbon atoms in standard conditions) at a potential close to metallic lithium and a moderate irreversible capacity can be obtained with graphite-based anodes. A higher degree of reversible lithium insertion than in graphite, but also an important irreversible capacity, is observed with various kinds of nanostructured carbons. Therefore, an intensive research effort is focused on the optimization of the anodic carbon materials, with the objectives to enhance the reversible capacity and to reduce as much as possible the irreversible capacity and hysteresis, which are often important drawbacks of these materials. The next section will discuss the correlations between the electrochemical performance of nanostructured carbons and their nanotexture/structure and surface functionality. Taking into account the key parameters that control the electrochemical properties, some optimizations proposed in literature will be presented. 

J. Li, Z. Tang, Z. Zhang, Controllable formation and electrochemical properties of one-dimensional nanostructured spinel Li4Ti50i2 , Electrochemistry Communications, 7, 894-899, (2005). 

We, therefore, need to know more about how to deal with and take advantage of the continuous flow of electrons across electronic nanostructures and ionic species in a nanoscale ionic conductor (electrolyte). Furthermore, it is also important to understand how charge transfer lengths are influenced on the nanoscale and how size affects electrochemical properties [8,30]. Accordingly, we will consistently address... 

To produce materials and systems with improved properties we must be able to modify the amount of interface and its properties in a controlled manner. The engineering of nanostructured electrodes depends on a more in-depth understanding of the nanoscale size effect properties of compounds and on the characterization and assembly of 2-D and/or 3-D nanostractured electrodes or cells. Any strategy for modifying these nanostractured electrodes in a speciQc way should involve the design of nanostructured electrodes with controlled electrochemical properties. 

In this chapter, we focus on the importance of nanoarchitecture in determining the electrochemical properties of transition metal oxide aerogels. After a brief introduction to aerogels and their synthesis methods we give an overview of the electrochemical characterization techniques employed when dealing with nanostructures. This chapter concludes with a case study on how aerogel nanostructures have improved the electrochemical properties of vanadium pentoxide. 

Case Study Effects of Nanostructure on the Electrochemical Properties of V2O5... 

Other uses of nanostructured chromophores may include fluorescent nanoparticles or nanoparticle-based porous materials that change their light absorption or emission when a toxin is encountered. Some metal oxides and POMs already exhibit such properties. Likewise, electrochemical properties, including induced photocurrents, could be sensitive to encountering a toxin. Clearly, both decontamination and detection are relevant aspects here. Basic research is needed on the design and synthesis of engineered nanostructures whose electronic structures, thermal catalytic, photophysical (emission), and photocatalytic properties are strongly perturbed by the presence or absence of toxic compounds. 

Their unusual structural and electronic properties make the carbon nanostructures applicable in, inter alia, the electrode materials of EDLCs and batteries. Activated carbon nanofibers are expected to be more useful than spherical activated carbon in allowing the relationship between pore structure and electrochemical properties to be investigated to prepare the polarizable electrodes for experimental EDLCs, EDLCs are well documented to exhibit significantly higher specific powers and longer cycle lifetimes compared with those of most of rechargeable batteries, including lead acid, Ni-MH, and Li-ion batteries [20-34—45],... 

X. Yu, Y. Li, and K. Kalantar-zadeh, Synthesis and electrochemical properties of template-based polyanihne nanowires and template-free nanofibril arrays Two potential nanostructures for gas sensors. Sens. Actuators B, 136, 1-7 (2009). 

The electrochemical synthetic techniques of nanostructured conducting polymers are mainly carried out using galvanostat, potentiostat, and cyclic voltammetry (CV)- The advantages of electrochemical over chemical preparation are that the sizes of the nano-particles are easily controlled by the applied potential, current density, scan rate, and the number of cycles, and especially that the nanostmctured conducting polymer deposited on the electrode material can be directly used to investigate its electrochemical properties and in situ spectroelectrochemical characteristics. 

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