Nanocomposite-enhanced electrochemical

Mn02 ternary nanocomposites and their enhanced electrochemical performance for supercapacitors. Electrochhn. Acta 71,27-32. 

Lithium-ion batteries require novel materials for increasing their cychng stability and power delivering capability. Polypyrrole/reduced graphene oxide nanocomposite is used as cathode in a lithium-ion battery and enhanced electrochemical properties are observed such as high rate capability and improved cycling stability [71 ]. 

Cao J, Hu G, Peng Z et al (2015) Polypyrrole-coated LiCo02 nanocomposite with enhanced electrochemical properties at high voltage for lithium-ion batteries. J Power Sources 281 49-55... 

Lu X, Dou H, Yuan C, Yang S, Hao L, Zhang F et al (2012) Polypyrrole/carbon nanotube nanocomposite enhanced the electrochemical capacitance of flexible graphene film for supercapacitors. J Power Sources 197 319-324... 

Wang J, Wu Z, Yin H, Li W, Jiang Y (2014) Poly (3, 4-ethylenedioxythiophene)/MoS2 nanocomposites with enhanced electrochemical capacitance performance. RSC Adv 4 56926-56932... 

Li X, Dhanabalan A, Wang C (2011) Enhanced electrochemical performance of porous NiQ-Ni nanocomposite anode for lithium ion batteries. J Power Sourc 196 9625-9630... 

Metal nanoparticles have received considerable attention in recent years. Incorporation of these metal particles into CNTs produces modified electrodes that have been observed to enhance the electrocatalytic activity of numerous electrochemical reactions and therefore he used for sensing applications. For instance, Luong and co-workers have reported the use of metal nanoparticle/CNT nanocomposites for electrochemical detection of trinitrotoluene (TNT) and other nitroaromatics. 

Wang, M. and Dong, S. (2007). Enhanced Electrochemical Properties of Nanocomposite Polymer Electrolyte Based on Copolymer with Exfoliated Clays. Journal of Power Sources. 170 425 32. 

The electrochemical deposition of doped silica, ORMOSIL and related nanocomposite thin films at the surface of electrodes is opening a whole new field of applications. In the latter case, a potential is applied to an alkoxide solution which alters the pH on the electrode surface and thus enhances the rate of condensation.40 The resulting single-step... 

In recent several years, super-capacitors are attracting more and more attention because of their high capacitance and potential applications in electronic devices. The performance of super-capacitors with MWCNTs deposited with conducting polymers as active materials is greatly enhanced compared to electric double-layer super-capacitors with CNTs due to the Faraday effect of the conducting polymer as shown in Fig. 9.18 (Valter et al., 2002). Besides those mentioned above, polymer/ CNT nanocomposites own many potential applications (Breuer and Sundararaj, 2004) in electrochemical actuation, wave absorption, electronic packaging, selfregulating heater, and PTC resistors, etc. The conductivity results for polymer/CNT composites are summarized in Table 9.1 (Biercuk et al., 2002). 

A polymer electrolyte with acceptable conductivity, mechanical properties and electrochemical stability has yet to be developed and commercialized on a large scale. The main issues which are still to be resolved for a completely successful operation of these materials are the reactivity of their interface with the lithium metal electrode and the decay of their conductivity at temperatures below 70 °C. Croce et al. found an effective approach for reaching both of these goals by dispersing low particle size ceramic powders in the polymer electrolyte bulk. They claimed that this new nanocomposite polymer electrolytes had a very stable lithium electrode interface and an enhanced ionic conductivity at low temperature. combined with good mechanical properties. Fan et al. has also developed a new type of composite electrolyte by dispersing fumed silica into low to moderate molecular weight PEO. 

While the variety of NPs used in catalytic and sensor applications is extensive, this chapter will primarily focus on metallic and semiconductor NPs. The term functional nanoparticle will refer to a nanoparticle that interacts with a complementary molecule and facilitate an electrochemical process, integrating supramolecular and redox function. The chapter will first concentrate on the role of exo-active surfaces and core-based materials within sensor applications. Exo-active surfaces will be evaluated based upon their types of molecular receptors, ability to incorporate multiple chemical functionalities, selectivity toward distinct analytes, versatility as nanoscale receptors, and ability to modify electrodes via nanocomposite assemblies. Core-based materials will focus on electrochemical labeling and tagging methods for biosensor applications, as well as biological processes that generate an electrochemical response at their core. Finally, this chapter will shift its focus toward the catalytic nature of NPs, discussing electrochemical reactions and enhancement in electron transfer. 

Nanocomposites in the form of superlattice structures have been fabricated with metallic, " semiconductor,and ceramic materials " " for semiconductor-based devices. " The material is abruptly modulated with respect to composition and/or structure. Semiconductor superlattice devices are usually multiple quantum structures, in which nanometer-scale layers of a lower band gap material such as GaAs are sandwiched between layers of a larger band gap material such as GaAlAs. " Quantum effects such as enhanced carrier mobility (two-dimensional electron gas) and bound states in the optical absorption spectrum, and nonlinear optical effects, such as intensity-dependent refractive indices, have been observed in nanomodulated semiconductor multiple quantum wells. " Examples of devices based on these structures include fast optical switches, high electron mobility transistors, and quantum well lasers. " Room-temperature electrochemical... 

Ma, L., Li, Y, Yu, X., Zhu, N., Yang, Q., and Noh, C.-H. 2008. Electrochemical preparation of PMeT/TiO2 nanocomposite electrochromic electrodes with enhanced long-term stability. Journal of Solid State Electrochemistry 12, 1503-1509. 

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