Niobium oxide electrodes

These batteries have vanadium oxide as the active material of the positive electrode, niobium oxide for the active material of the negative electrode, and an organic solvent for the electrolyte. Lithium ions enter the vanadium oxide from the niobium oxide during discharge, and lithium ions enter the niobium oxide from the vanadium... 

Fig. 8-42. Anodic and cathodic polarization curves observed for electron transfer of hydrated redox particles at an electrode of metallic niobium covered with a thick niobium oxide NbsOs film (12 nm thick) in acidic solution reaction is an electron transfer of hydrated redox particles, 0.25MFe(CN)6 /0.25M Fe(CN)g, in 0.1 M acetic add buffer solution of pH 4.6 at 25 C. =...

The direct voltammetry and bioelectrocatalytic activity of cytochrom c. HRP immobilized onto niobium oxide (Nb2Os) mesoporous matrix at inidium-tin oxide (ITO) electrode was investigated [282,283],The electron transfer rate constant of cytochrom c is 0.28 s"1, reflective of the intrinsic electron transfer rate. In addition mesoporous niobium... 

Lactate dehydrogenase (LDH) has been immobilized on silica gel coated with niobium oxide carbon paste electrode for the development of lactate biosensor. This biosensor shows good sensitivity allows lactate estimation upto 6.5 x 10-6 mol L-1. Moreover, the biosensor shows linear range from 0.1 to 14 mmol L-l for lactate. [111]. 

The collector electrode was made at the Electrotechnical Laboratory by sputtering niobium oxide with a low work function of 1.38 eV on a Mo electrode [9]. A TIC device with a maximum output power of 8 W/cm obtained at an emitter-collector temperature differential of 1600°C-760°C and a Cs reservoir temperature of 330°C was assembled at Mitui Engineering Ship Building Co.Ltd. [10]. 

Lampert and coworkers [36] have used a modified amorphous PEO-LiCFaSOs electrolyte for the realization of WO3 laminated windows using several types of counter-electrodes, such as niobium oxide, nickel oxide and a new class of solid redox polymerization electrodes [63]. These latter electrodes have an advantage over inorganic layers in that they can be tailored to the electrochromic material and ion specifically. Figure 8.18 illustrates the optical transmittance of a EW made of WOa/modified a-PEO/ion storage polymer [63]. 

L-lactate Lactate oxidase and meldola s blue adsorbed on Si02 particles coated with niobium oxide and dispersed in a cartxm paste electrode Bio- and electro- catalysis [205]... 

Orilall, M. C., Matsumoto, R, Zhou, Q., Sai, H., Abruna, H. D., DiSalvo, F. J., and Wiesner, U. 2009. One-pot synthesis of platinum-based nanoparticles incorporated into mesoporous niobium oxide-carbon composites for fuel cell electrodes. 131(26),... 

Zhang, L., Wang, L. Y, Holt, C. M. B., Zahiri, B., Li, Z., Navessin, T., Malek, K., Eikerling, M., and Mitlin, D. 2012. Highly corrosion resistant platinum-niobium oxide-carbon nanotube electrodes for the oxygen reduction in PEM fuel cells. 5(3), 6156-... 

L. Zhang, L. Wang, C.M.B. Holt, B. Zahiti, K. Malek, T. Navessin, M.H. Eikerling, and D. Mitlin, Highly corrosion resistant platinum-niobium oxide-carbon nanotube electrodes for PEFC oxygen reduction reaction. Ener rmwm Sa. 5, 6156-6172, 2012. 

Ohtani B., Iwai K., Nishimoto S.-I, Inui T. Electrochromism of Niobium oxide thin films prepared by the sol-gel process. J. Electrochem. Soc. 1994 141(9) 2439-2442 Opara KraSovec U., OrelB., HoSevar S., Muievi I. Electrochemical and spectroelectrochemical properties of Sn02 and Sn02/Mo transparent electrodes with high ion-storage capacity. J. Electrochem. Soc. 1997 144(10) 3398-3409... 

This system typically uses sulfuric acid as the electrolyte with a proton exchange membrane. While a porous separator could be used, for high efficiency operation, ion-selective membranes are generally preferred as vanadium crossover leads to losses in coulombic efficiency. At present, Nafion is the membrane of choice as V(V) is a powerful oxidizing agent, which can attack cheaper hydrocarbon-based ion selective membranes [21]. The redox reactions of different vanadium species have displayed reversibility and high activity on carbon based electrodes. Moreover, Li et al. discovered the catalytic effects of bismuth nanoparticles on V(II)/V(III) [51] and of niobium oxide nanorods on both V(II)Af(lII) and V(IV)Af(V) [52], which have been shown to further enhance the energy efficiency of the VRB by more than 10 %. 

Josephson junctions using NbN as electrodes have been developed in several institutes. Amorphous silicon (a-Si), niobium oxide (NbO t), magnesium oxide (MgO), aluminum oxide (A10 t), and aluminum nitride (AIN) have been investigated as tunnel barriers for all NbN junctions. 

The impressed current method with metal oxide-coated niobium anodes is usually employed for internal protection (see Section 7.2.3). In smaller tanks, galvanic anodes of zinc can also be used. Potential control should be provided to avoid unacceptably negative potentials. Pure zinc electrodes serve as monitoring and control electrodes in exposed areas which have to be anodically cleaned in the course of operation. Ag-AgCl electrodes are used to check these reference electrodes. 

Oxide ratio, 18 815 Oxides, 16 598 acidic, 22 190-191 bond strengths and coordination numbers of, 22 570t diorganotin, 24 819 glass electrodes and, 14 28 gold, 22 707 iron, 14 541-542 lead, 14 786-788 manganese, 15 581-592 nickel, 27 106-108 niobium, 27 151 plutonium, 29 688-689 in perovskite-type electronic ceramics, 14 102... 

An example of recent achievement in this area is a flexible, thin film Cu(In,Ga)Se2 solar cell deposited on a titanium foil, which was combined with a TiC>2 photocatalyst layer and modified by a niobium-doped titanium oxide front electrode to function as a photoelectrochemical tandem cell/membrane for a direct light-driven hydrogen evolution from an aqueous solution [48], Under illumination with UV/vis light, the system produced up to 0.052 pLH2/scm2 (e.g. the hydrogen formation rate was approximately 7,250 pmol/h g relative to the amount of TiC>2 used). Several aspects of the operating principles of the photoelectrochemical devices, the materials requirements, main bottlenecks, and the various device concepts (in relation to H2... 

Despite the superior chemical stability of the diamond layer, these electrodes face two challenges. The brittle nature of crystalline silicon limits the mechanical stability of the support, causing eventual loss of the BDD electrode by friction. Furthermore, any contact with the organic electrolyte has to be strictly eliminated, since silicon or niobium support is very prone to corrosion if non-aqueous electrolysis conditions are applied. In contrast to aqueous media, no passivation occurs by oxide... 

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