Publications by authors named "Samia A Kosa"

In this research, copper (II) oxide nanoparticles were prepared by an ecofriendly green method using the extract of leaves (Molokhaia) as a surfactant, capping and anti-agglomeration agent. The ecofriendly green CuO NPs were characterized using different chemical and physical techniques and the results confirmed the formation of monoclinic tenorite CuO nanoparticles with an average particle size of 12 nm and BET surface area of 11.1 m/g.

View Article and Find Full Text PDF

The decolorization of brilliant blue (E133) in aqueous solution by KSO and NaBH with AgNPs as an activator was studied spectrophotometrically under normal laboratory conditions. Batch experiments were performed to investigate the effects of reaction time, initial dye concentration, activator concentration, solution pH, and temperature on the decolorization of E133. KSO and NaBH did not decolorize the dye E133 in the absence of AgNPs.

View Article and Find Full Text PDF

Natural red purple dye, Betanin, was extracted from the beetroot, purified by aqueous two- phase extraction and gel permeation column chromatography, and used as a reducing agent for the synthesis of silver-betanin core-shell triangular nanodisks for the first time. Spectroscopic data show that the nanoparticle structure is core@shell like with Ag as core and betanin as shell. Langmuir monolayer model (q = 32.

View Article and Find Full Text PDF

Donor-π-bridge-donor type oligomers (D-π-D) have been studied intensively as active materials for organic optoelectronic devices. In this study, we introduce three new D-π-D type organic semiconductors incorporating thiophene or thienothiophene with two electron-rich TPA units, which can be easily synthesized from commercially available materials. A thorough comparison of their optoelectronic and structural properties was conducted, revealing the strong influence of the extent of longitudinal π-bridge conjugation on both the solid structure of the organic semiconductive materials and their photovoltaic performance when applied as hole transporting materials (HTM) in perovskite solar cells.

View Article and Find Full Text PDF

The recent advances in perovskite solar cells (PSCs) created a tsunami effect in the photovoltaic community. PSCs are newfangled high-performance photovoltaic devices with low cost that are solution processable for large-scale energy production. The power conversion efficiency (PCE) of such devices experienced an unprecedented increase from 3.

View Article and Find Full Text PDF

We demonstrate for the first time an asymmetric squaraine-based low band-gap hole transporting material, which acted as both light harvesting and hole transporting layers in methylammonium lead triiodide perovskite solar cells. Opto-electrochemical characterization revealed extremely high molar extinction coefficients of the absorption bands in the low energy region and prominent space charge delocalization due to its electronically asymmetric nature. A suitable band alignment of the squaraine HOMO level with the valence band edge of the perovskite, and the conduction band of the TiO2 with LUMO of the perovskite allowed a cascade of hole extraction and electron injection, respectively.

View Article and Find Full Text PDF

A series of novel monobenzyl-substituted deuteriofullerenes (BnDCs) were synthesized efficiently through Co-catalyzed selective monofunctionalization of C60. Bulk heterojunction solar cells, based on poly(3-hexylthiophene) as the donor and BnDCs as the acceptors, exhibited higher photovoltaic performances as compared to the corresponding protonated BnHCs devices.

View Article and Find Full Text PDF

Photoelectrocatalytic disinfection of E. coli by an iron doped TiO(2) sol-gel electrode is shown to be more efficient than disinfection by the corresponding undoped electrode. Thus, the improvements in photocatalytic efficiency associated with selective doping have been combined with the electric field enhancement associated with the application of a small positive potential to a UV irradiated titanium dioxide electrode.

View Article and Find Full Text PDF