The future of circuit miniaturization is based on the development of novel functional materials a... more The future of circuit miniaturization is based on the development of novel functional materials and the improvement of nanofabrication and characterization techniques. The performance of semiconductor electronics is coupled to the resolution of the lithographic process; and to keep pace with historic growth rates (e.g., Moore's Law), the dimensions of critical circuit elements are shrinking toward 10 nm. The development of micro- and nano- technology depends on the ability to fabricate micro and nanosized structures with high recision. The most sophisticated semiconductor devices, such as microprocessors and memory chips, are patterned with top-down projection lithographic techniques. In parallel, the bottom-up approach is based on hierarchical self-assembly of complex structures departing from molecular building blocks through molecular recognition and molecule-surface interactions. There are advantages and drawbacks in both approaches. In top-down methodologies further downsiz...
A commercial grade carbon black was chemically modified using mineral acids (either with HNO 3 or... more A commercial grade carbon black was chemically modified using mineral acids (either with HNO 3 or H 2SO 4 or mixture) and the sorption performance of the virgin and modified forms were investigated. Chemical modification resulted in the creation of surface acidic functional groups ( sbnd COOH, sbnd SO 2OH) and was verified by FTIR spectra. This was further verified by TGA analysis revealing higher weight loss characteristics of the modified carbons in comparison to virgin carbon black. Morphological changes were observed from BET surface area measurements and SEM analysis. XRD study revealed the change of graphitic crystallite size as a result of modification. The suspension pH of the materials in deionized water and the point of zero charge (pH pzc) in inert electrolyte were determined. The measured values of suspension pH and pH pzc for all the carbons were found to be acidic with more acidic character in the modified carbons. These materials were used as sorbents for the removal of arsenic from aqueous medium and showed excellent adsorption performance.
ABSTRACT A method for providing a nanopattern of periodically ordered metal oxide nanostructures ... more ABSTRACT A method for providing a nanopattern of periodically ordered metal oxide nanostructures on a substrate is described. The method comprises the steps of providing a microphase separated block copolymer as a thin film on a substrate, the block copolymer comprising a first polymer having an affinity for a cations of the metal and a second polymer having a lower affinity for the cations than the first polymer, and selectively incorporating a salt of the metal cation into the first polymer of the block copolymer by means of a solvation process prior to or after formation of the microphase separated block copolymer. The block copolymer film is then treated to oxidise the metal ion salt and remove the polymers leaving a nanopattern of metal oxide nanostructures on the substrate.
The future of circuit miniaturization is based on the development of novel functional materials a... more The future of circuit miniaturization is based on the development of novel functional materials and the improvement of nanofabrication and characterization techniques. The performance of semiconductor electronics is coupled to the resolution of the lithographic process; and to keep pace with historic growth rates (e.g., Moore's Law), the dimensions of critical circuit elements are shrinking toward 10 nm. The development of micro- and nano- technology depends on the ability to fabricate micro and nanosized structures with high recision. The most sophisticated semiconductor devices, such as microprocessors and memory chips, are patterned with top-down projection lithographic techniques. In parallel, the bottom-up approach is based on hierarchical self-assembly of complex structures departing from molecular building blocks through molecular recognition and molecule-surface interactions. There are advantages and drawbacks in both approaches. In top-down methodologies further downsiz...
A commercial grade carbon black was chemically modified using mineral acids (either with HNO 3 or... more A commercial grade carbon black was chemically modified using mineral acids (either with HNO 3 or H 2SO 4 or mixture) and the sorption performance of the virgin and modified forms were investigated. Chemical modification resulted in the creation of surface acidic functional groups ( sbnd COOH, sbnd SO 2OH) and was verified by FTIR spectra. This was further verified by TGA analysis revealing higher weight loss characteristics of the modified carbons in comparison to virgin carbon black. Morphological changes were observed from BET surface area measurements and SEM analysis. XRD study revealed the change of graphitic crystallite size as a result of modification. The suspension pH of the materials in deionized water and the point of zero charge (pH pzc) in inert electrolyte were determined. The measured values of suspension pH and pH pzc for all the carbons were found to be acidic with more acidic character in the modified carbons. These materials were used as sorbents for the removal of arsenic from aqueous medium and showed excellent adsorption performance.
ABSTRACT A method for providing a nanopattern of periodically ordered metal oxide nanostructures ... more ABSTRACT A method for providing a nanopattern of periodically ordered metal oxide nanostructures on a substrate is described. The method comprises the steps of providing a microphase separated block copolymer as a thin film on a substrate, the block copolymer comprising a first polymer having an affinity for a cations of the metal and a second polymer having a lower affinity for the cations than the first polymer, and selectively incorporating a salt of the metal cation into the first polymer of the block copolymer by means of a solvation process prior to or after formation of the microphase separated block copolymer. The block copolymer film is then treated to oxidise the metal ion salt and remove the polymers leaving a nanopattern of metal oxide nanostructures on the substrate.
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