Optical nonlinearity and all-optical switching in pumpkin seed oil based on the spatial cross-phase modulation (SXPM) technique.

Nonlinear optics (NLO) and its applications have attracted increasing research interest in recent years owing to their contribution to the development of photonic technology. Accordingly, in this study, we investigated the NLO response of pumpkin seed oil using the spatial self-phase modulation (SSPM) method. Significant NLO characteristics have been experimentally studied at and continuous wave (CW) laser wavelengths, yielding second-order nonlinear refractive index ( ) values of and , respectively.

Inverted organic solar cells with non-clustering bathocuproine (BCP) cathode interlayers obtained by fullerene doping.

Bathocuproine (BCP) is a well-studied cathode interlayer in organic photovoltaic (OPV) devices, where it for standard device configurations has demonstrated improved electron extraction as well as exciton blocking properties, leading to high device efficiencies. For inverted devices, however, BCP interlayers has shown to lead to device failure, mainly due to the clustering of BCP molecules on indium tin oxide (ITO) surfaces, which is a significant problem during scale-up of the OPV devices. In this work, we introduce C doped BCP thin films as cathode interlayers in inverted OPV devices.

Inorganic Surface Engineering to Enhance Perovskite Solar Cell Efficiency.

The photoconversion efficiency of perovskite solar cells (PSCs) is enhanced by the deposition of inorganic nanoparticles (NPs) at the interface between the compact TiO electron-selective contact and the mesoporous TiO film. The NPs used are core/shell Au@SiO, where a thin SiO coating protects the Au core from the direct chemical interaction with CHNHPbI halide perovskite used as light-harvesting material. The samples prepared with Au@SiO NPs exhibit a higher external quantum efficiency in the complete wavelength range at which perovskite presents light absorption and not just at the wavelengths at which Au@SiO NPs present their absorption peak.

Development of a novel mixed hemimicelles dispersive micro solid phase extraction using 1-hexadecyl-3-methylimidazolium bromide coated magnetic graphene for the separation and preconcentration of fluoxetine in different matrices before its determination by fiber optic linear array spectrophotometry and mode-mismatched thermal lens spectroscopy.

This study aims at developing a novel, sensitive, fast, simple and convenient method for separation and preconcentration of trace amounts of fluoxetine before its spectrophotometric determination. The method is based on combination of magnetic mixed hemimicelles solid phase extraction and dispersive micro solid phase extraction using 1-hexadecyl-3-methylimidazolium bromide coated magnetic graphene as a sorbent. The magnetic graphene was synthesized by a simple coprecipitation method and characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy and scanning electron microscopy (SEM).

Iron oxide functionalized graphene oxide as an efficient sorbent for dispersive micro-solid phase extraction of sulfadiazine followed by spectrophotometric and mode-mismatched thermal lens spectrometric determination.

A simple and rapid dispersive micro-solid phase extraction (DMSPE) combined with mode-mismatched thermal lens spectrometry as well as fiber optic linear array spectrophotometry was developed for the separation, extraction and determination of sulfadiazine. Graphene oxide was synthesized using the modified Hummers method and functionalized with iron oxide nanoparticles by means of a simple one step chemical coprecipitation method. The synthesized iron oxide functionalized graphene oxide was utilized as an efficient sorbent in DMSPE of sulfadiazine.

Preconcentration, speciation and determination of ultra trace amounts of mercury by modified octadecyl silica membrane disk/electron beam irradiation and cold vapor atomic absorption spectrometry.

Mercury (II) and methyl mercury cations at the Sub-ppb level were adsorbed quantitatively from aqueous solution onto an octadecyl-bonded silica membrane disk modified by 2-[(2-mercaptophyenylimino)methyl] phenol (MPMP). The trapped mercury was then eluted with 3ml ethanol and Hg2+ ion was directly measured by cold vapor atomic absorption spectrometry, utilizing tin (II) chloride. Total mercury (Hgt) was determined after conversion of MeHg+ into Hg2+ ion by electron beam irradiation.