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This study developed a safe and sustainable route for the epoxidation of cyclohexene using water as the source of oxygen at room temperature and ambient pressure. Here, we optimized the cyclohexene concentration, volume of solvent/water (CH3CN, H2O), time, and potential on the photoelectrochemical (PEC) cyclohexene oxidation reaction of the α-Fe2O3photoanode. The α-Fe2O3photoanode epoxidized cyclohexene to cyclohexene oxide with a 72.4 ± 3.6% yield and a 35.2 ± 1.6% Faradaic efficiency of 0.37 V vs Fc/Fc+(0.8 VAg/AgCl) under 100 mW cm–2. Furthermore, the irradiation of light (PEC) decreased the applied voltage of the electrochemical cell oxidation process by 0.47 V. This work supplies an energy-saving and environment-benign approach for producing value-added chemicals coupled with solar fuel generation. Epoxidation with green solvents via PEC methods has a high potential for different oxidation reactions of value-added and fine chemicals.

This study provided the preparation and application of a highly efficient photoanode having dense and efficient sodium titanate (NTO) nanorods decorated with CdS nanoparticles. The (NTO) nanorods were grown densely on the surface of Ti foil by a one-step hydrothermal method, which provides many step edges on the surface of the nanorods and a direct pathway for transfer of photogenerated electrons to the Ti substrate to improve the water splitting ability. The CdS nanoparticles were deposited on the surface of NTO nanorods using a simple and low-cost successive ionic layer adsorption and reaction (SILAR) method to greatly enhance the absorption of visible light. Rough surfaces of the as-synthesized nanorods were favorable sites for growing the CdS nanoparticles, which formed a tremendous connection and heterojunction at the interface between NTO and CdS. This efficient connection caused a noticeable enhancement in photocurrent density with great stability in integrated NTO/CdS photoanodes, due to the efficient separation and transfer of charge carriers. The NTO/CdS12 electrode with optimum SILAR cycles showed the highest photocurrent density around 2.37 mA cm−2at 1 V vs.RHE, which was 36 times higher than that of pure NTO (around 0.066 mA cm−2), and interestingly, this electrode retained more than 95% of its initial photocurrent density, even after 6000 seconds.

A facile and cost-effective method was developed for the synthesis of “magnetite/reduced graphene oxide” nanocomposite, as an anode material for lithium-ion batteries. The fabricated composite was characterized by different instrumental analyses including XRD, Raman, XPS, SEM, TEM, and FTIR, as well as various electrochemical (i.e. battery) tests. Such broad examination revealed the structure of the prepared material and its electrochemical behavior. It was found that the fabricated composite has a number of advantages over the currently utilized electrode materials such as cost efficiency, high Li ion storage (2528 mAh/g at 0.05 A/g at 1st discharge), cycle stability of 986 mAh/g over 100 cycles at a current density of 0.1 A/g, and eventually Coulombic efficiency of about 100 %. In comparison, the reduced graphene oxide (rGO) shows inferior performances, such as a constant capacity of 462 mAh/g, and a slower kinetics of the ion storage. Consequently, the synthesized low-cost anode material seems to be an attractive candidate for development of the next-generation energy-storage devices, used in electrical vehicles, and portable electronic instruments.

Graphene oxide-polyvinyl chloride composite was prepared using tetrahydrofuran solvent-assisted dispersion of characterized nano flakes of graphene oxide in polymer matrix. Electrical percolation threshold of GO/PVC nanocomposite was determined via a finite element simulation method with a 2D model and compared with experimental results. A conductive cell with two silver coated walls was designed and fabricated for exploring dosimetric properties of the composite. Some characteristics of the new nanocomposite such as linearity of dose response, repeatability, sensitivity and angular dependence are investigated. According to 2D proposed method, obtained data associated to electrical conductivity of the GO/polymer composite for PVC matrix plotted in different GO weight percentages and had good compatibility (validity) with experimental data. The dose response is linear in the 17–51 mGy dose range and it can be introduced for gamma radiation dosimetry in diagnostic activities.

Graphene oxide (GO) nanosheets were hybridized with Fe3O4nanoparticles (NPs) to form magnetic GO (MGO) and were further labeled by [68Ga]GaCl3as a potential drug delivery system. Paper chromatography, Fourier transform infra red (FTIR) spectroscopy, low-angle X-ray diffraction (XRD), CHN and atomic force microscopy (AFM) were utilized to characterize the trinary composite ([68Ga]@MGO). Biological evaluations of the prepared nanocomposite were performed in normal Sprague Dawley rats and it was found to be a possible host for theranostic radiopharmaceuticals. The results showed that the grafting of Fe3O4NPs on nanocomposite reduced the unwanted liver and spleen uptakes and increased the ratio of kidney/liver uptake from 0.037 to 1.07, leading to the fast removal of radioactive agent and less imposed radiation to patients. The high level of hydrogen bonding caused by the presence of functional groups is responsible for this effect. Considering the accumulation of the tracer in vital organs of rat (especially brain), efficient iron oxide grafting, fast wash-out, the short half-life gallium-68 and less imposed radiation doses to patients, this nanocomposite could be a suitable candidate for positron emission tomography (PET) studies and imaging applications.

In this study, a facile approach has been successfully applied to synthesize a W-doped Fe2O3/MoS2core–shell electrode with unique nanostructure modifications for photoelectrochemical performance. A two-dimensional (2D) structure of molybdenum disulfide (MoS2) and tungsten (W)-doped hematite (W:α-Fe2O3) overcomes the drawbacks of the α-Fe2O3and MoS2semiconductor through simple and facile processes to improve the photoelectrochemical (PEC) performance. The highest photocurrent density of the 0.5W:α-Fe2O3/MoS2photoanode is 1.83 mA·cm–2at 1.23 V vs reversible hydrogen electrode (RHE) under 100 mW·cm2illumination, which is higher than those of 0.5W:α-Fe2O3and pure α-Fe2O3electrodes. The overall water splitting was evaluated by measuring the H2and O2evolution, which after 2 h of irradiation for 0.5W:α-Fe2O3/MoS2was determined to be 49 and 23.8 μmol.cm–2, respectively. The optimized combination of the heterojunction and metal doping on pure α-Fe2O3(0.5W:α-Fe2O3/MoS2photoanode) showed an incident photon-to-electron conversion efficiency (IPCE) of 37% and an applied bias photon-to-current efficiency (ABPE) of 26%, which are around 5.2 and 13 times higher than those of 0.5W:α-Fe2O3, respectively. Moreover, the facile fabrication strategy can be easily extended to design other oxide/carbon-sulfide/oxide core–shell materials for extensive applications.