Novel Materials in Perovskite Solar Cells: Efficiency, Stability, and Future Perspectives.

Solar energy is regarded as the finest clean and green energy generation method to replace fossil fuel-based energy and repair environmental harm. The more expensive manufacturing processes and procedures required to extract the silicon utilized in silicon solar cells may limit their production and general use. To overcome the barriers of silicon, a new energy-harvesting solar cell called perovskite has been gaining widespread attention around the world. The perovskites are scalable, flexible, cost-efficient, environmentally benign, and easy to fabricate. Through this review, readers may obtain an idea about the different generations of solar cells and their comparative advantages and disadvantages, working mechanisms, energy alignment of the various materials, and stability achieved by applying variable temperature, passivation, and deposition methods. Furthermore, it also provides information on novel materials such as carbonaceous, polymeric, and nanomaterials that have been employed in perovskite solar in terms of the different ratios of doping and composite and their optical, electrical, plasmonic, morphological, and crystallinity properties in terms of comparative solar parameters. In addition, information on current trends and future commercialization possibilities of perovskite solar have been briefly discussed based on reported data by other researchers.

Excessive iodine in iodized household salt in Nepal.

Iodine is an essential trace element required for the regulation of physiological processes involving the thyroid gland. However, inadequate and excessive intake of iodine are responsible for health problems, such as iodine deficiency disorders, hypothyroidism, hyperthyroidism, thyroiditis, thyroid papillary cancer, and thyrotoxicosis. The Universal Salt Iodization (USI) program has become successful in providing supplemental iodine at the population level globally. Packaging quality, fortification level, and transportation and storage conditions of iodized salt determine the availability of iodine. Previous studies have reported severe health issues caused by excessive iodine intake after the implementation of the USI program. To understand the levels of iodine, we collected 2117 household salt samples from seven districts of Nepal and tested them for iodine content; among them, 98.1% were iodized. Overall median concentration of iodine was 53.9 ppm (range: 43.5-61.4 ppm). The majority (67.2%) of samples had iodine in the range of 45-75 ppm. Approximately 0.9% of samples had inadequate, 13.3% contained adequate, and 83.9% had excessive iodine than the World Health Organization-recommended value. Iodine content varied among the sampling districts and seasons, to some extent. Our study confirmed that iodized salt is widely used in Nepal and is excessively iodized. Excessive intake of iodine through iodized salt requires further attention by policy makers. The iodine level may need adjustment to address the health impact.

Effective photocatalytic efficacy of hydrothermally synthesized silver phosphate decorated titanium dioxide nanocomposite fibers.

Hierarchical Ag3PO4/TiO2 nanocomposite fibers were prepared by combining electrospinning technique and hydro-thermal growth method. As-synthesized samples were characterized by using field-emission scanning electron microscopy (FE-SEM), Transmission electron microscopy (TEM), X-ray diffraction (XRD), Photoluminescence (PL), and Fourier transform infra-red (FT-IR) spectroscopy. The FE-SEM image revealed a uniform decoration of Ag3PO4 nanoparticles without aggregation on primary TiO2 nanofibers. The photocatalytic and antibacterial studies were performed and results were shown that the Ag3PO4/TiO2 nanocomposite fibers show an enhanced photocatalytic and antibacterial activity toward the degradation of dye methylene blue and bacteria (Escherichia coli, Staphylococcus aureus) respectively. Our results can provide new insights of Ag3PO4/TiO2 nanocomposite fibers for the potential applications in antibacterial and waste water treatment.

Facile synthesis of luminescent and amorphous La2O3-ZrO2:Eu³âº nanofibrous membranes with robust softness.

Novel luminescent and amorphous La2O3-ZrO2:Eu(3+) (LZE) nanofibrous membranes with robust softness are fabricated for the first time via a facile electrospinning technique. By incorporating zirconium oxide, the as-prepared lanthanum oxide nanofibrous membranes can be dramatically changed from extreme fragility to robust softness. Meanwhile, the softness and luminescent performance of LZE nanofibrous membranes can be finely controlled by regulating the doping concentration of zirconium oxide and europium in lanthanum oxide nanofibers. Additionally, the crystal structure analysis using X-ray diffractometer and high resolution transmission electron microscopy measurements have confirmed the correlation between the amorphous structure and softness. Furthermore, LZE membranes show the characteristic emission of Eu(3+) corresponding to (5)D(0, 1, 2)-(7)F(0, 1, 2, 3, 4) transitions due to an efficient energy transfer from O(2-) to Eu(3+). The LZE nanofibrous membranes with the optimum doping Eu(3+) concentration of 3 mol% exhibit excellent softness and luminescent properties, which make the materials to have potential applications in fluorescent lamps and field emission displays.

Synthesis and photocatalytic activities of CdS/TiO2 nanoparticles supported on carbon nanofibers for high efficient adsorption and simultaneous decomposition of organic dyes.

CdS/TiO2 NPs-decorated carbon nanofibers were prepared by a simple electrospinning method followed by the calcination under argon atmosphere. As-synthesized nanocomposites exhibited a strong photocatalytic activity for decomposition of methylene blue (MB), reactive black 5, and reactive orange 16 under visible light radiation for many successive cycles. Moreover, in the dark, the carbon content revealed very good adsorption behavior as 95% of the dye was removed within 5 min, however less adsorption capacity was observed upon successive cycles. Therefore, the enhanced photocatalytic performance for the introduced nanofibers might be attributed to the adsorption characteristic of carbon nanofiber and the known photocatalytic activities of the TiO2 and CdS photocatalysts.