A study of white light emission from magic sized CdSe quantum dots is reported. Quantum dots were synthesized using a hot solution method and exhibited strong white light with a quantum yield in the range of 10-30%. The emission of white light was attributed to photoluminescence (PL) from both excitons and surface states.
View Article and Find Full Text PDFWhite light electroluminescence (EL) was obtained by mixing emission from singlet and triplet excimers from a single poly (n-vinylcarbazole) (PVK) spin cast layer after irradiation of the solution with UV light. With increased UV light irradiation, the intensity from the triplet excimer (red-630 nm) of PVK increased compared with that of the singlet excimer (blue-460 nm) due to an increased population of both adjacent benzene rings being aligned with one another (fully overlapping) versus only one of the adjacent benzene rings being aligned (partially overlapping). The emission color changed from blue to white with increased UV irradiation time while the EL brightness and current density decreased and the turn-on voltage increased.
View Article and Find Full Text PDFCarbon nanostructures are synthesized using a novel arc-discharge in solution process. A multitude of defects on nanotubes and nanostructures is found. Evidence of these defects in as-synthesized carbon nanostructures is explored using high-resolution transmission electron microscopy (HRTEM).
View Article and Find Full Text PDFA parametric study was carried out on a novel carbon nanotube (CNT) synthesis using 'arc-discharge in solution' (ADS). The carbon nanostructure yield as a function of time, the rate of erosion of the anode, and the rate of deposition of carbonaceous materials on the cathode electrode were investigated. Amperage dependent normalized kinetic parameters were evaluated.
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