Surface-modified carbons

Chem. Descrip. Calcium carbonate, surface modified with 1% stearates Chem.Artalysis CaCOa (96.5%), MgCO, (2%), SiOa (1,2%)... 

Nitric acid treatment lowered the methane uptake by about ten percent. This could be due to oxygen occupying sites within pores, but may be the result of weaker interaction between methane and an oxide surface as is observed for silica. Reduction of these treated carbons with hydrogen restored their original methane uptake. Clearly for methane storage, there is no advantage in modifying the carbon surface by nitric acid treatment. 

In order to improve the electrochemical performance with respect to lower irreversible capacity losses, several attempts have been made to modify the carbon surface. Here the work of Peled s [38, 130-132] and Takamura s groups [133-138] deserves mention. A more detailed discussion can be found Chapter III, Sec. 6. 

This fascinating product will still continue to develop to accommodate new applications, safety, health and environment (SHE) issues, advantages of novel materials like nano-composites, plasma-surface-modified carbon black, development of computer simulation techniques, and finally to develop a cybernetic or thinking tire. 

The large size of redox enzymes means that diffusion to an electrode surface will be prohibitively slow, and, for enzyme in solution, an electrochemical response is usually only observed if small, soluble electron transfer mediator molecules are added. In this chapter, discussion is limited to examples in which the enzyme of interest is attached to the electrode surface. Electrochemical experiments on enzymes can be very simple, involving direct adsorption of the protein onto a carbon or modified metal surface from dilute solution. Protein film voltammetry, a method in which a film of enzyme in direct... 

For the electrochemical capacitors of Carbon-Ni Oxide system with aqueous KOH solution it is expedient to use carbonaceous graphite materials with expanded structure and modified surface. The best results were achieved with carbon surface doped with Boron, which makes this carbon superior than other conductive additives used in this study, due to its... 

In conclusion, the surface modified natural graphite has good performance in PC based electrolyte and also meets the power requirements for hybrid electrical vehicle applications. Surface carbon coated natural graphite SLC1015 is a very promising material in high power Li-ion batteries with lower cost, reasonable safety, and low irreversible capacity. 

Surface modified NO sensors incorporate an electrode surface that has been modified or treated in some way so as to increase the selectivity of the sensor for NO and promote catalytic oxidation of NO. An early example of such a sensor was presented by Malinski and Taha in 1992 [27], In this publication an —500nm diameter carbon fiber electrode was coated with tetrakis(3-methoxy-4-hydroxyphenyl)porphyrin, via oxidative polymerization, and Nation. This electrode was shown to have a detection limit of — lOnM for NO and great selectivity against common interferences. However, recently it has been shown that this electrode suffers severe interference from H202 [28],... 

The fluorine atom, by virtue of its electronegativity, size, and bond strength with carbon, can be used to create compounds with remarkable properties. Small molecules containing fluorine have many positive impacts on everyday life of which blood substitutes, pharmaceuticals, and surface modifiers are only a few examples. 

Although there have been great advances in covalent functionalization of fullerenes to obtain surface-modified fullerene derivatives or fullerene polymers, the application of these compounds in composites still remains unexplored, basically because of the low availability of these compounds [132]. However, until now, modified fullerene derivatives have been used to prepare composites with different polymers, including acrylic [133,134] or vinyl polymers [135], polystyrene [136], polyethylene [137], and polyimide [138,139], amongst others. These composite materials have found applications especially in the field of optoelectronics [140] in which the most important applications of the fullerene-polymer composites have been in the field of photovoltaic and optical-limiting materials [141]. The methods to covalently functionalize fullerenes and their application for composites or hybrid materials are very well established and they have set the foundations that later were applied to the covalent functionalization of other carbon nanostructures including CNTs and graphene. 

Other successful but limited surface modifying trials have been done such as Pt dispersed onto Ti02, Pt-Co and Mn perovskite , Pt-transition metal oxides , Pt-Au-Fe203 or Ru02- These materials are known as gas-solid interface carbon monoxide catalysts and have been... 

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