Perovskite solar cells have been attracting extensive attention because of their superior photovoltaic performances and lower costs as compared to those of prevailing photovoltaic technologies. There are four main interfaces in perovskite solar cells flourine-doped tin oxide/electron transport layer, electron transport layer/perovskite layer, perovskite layer/hole transport layer, and hole transport layer/metal electrode. Among them, the interface between the perovskite layer (general formula RPbX₃) and electron transport layer significantly affects the power conversion efficiency. In this study, a layer of TiO₂, which is the most popular metal oxides used for perovskite solar cells applications, was deposited as the electron transport layer. To enhance the perovskite solar cells performance, surface treatment was performed with TiCl₄ (80 mM). To investigate the effect of TiCl₄ treatment, ultraviolet-visible spectroscopy was performed on the perovskite film. Atomic force microscopy, X-ray diffraction, scanning electron microscopy and performance of perovskite solar cells have been also evaluated in this paper. The results indicated that the TiCl₄ treatment significantly improved the perovskite solar cells performance.In this investigation we report the formation of thin ZnO recombination barrier layer at TiO₂/CdS interface aimed for the improvement in performance of CdS sensitized solar cell. The film was deposited upon nanocrystalline mesoporous TiO₂ surface by following a simple chemical process and characterized, using UV-Visible spectroscopy, X-ray diffraction and electron dispersive X-ray measurements. The insertion of ZnO thin layer enhances the QDSC (Quantum dot sensitized solar cell) performance, contributed mainly by an increase in open circuit voltage (Voc) due to reduced electron **** transfer from TiO₂ conduction band. Moreover, the analysis of photovoltaic characteristics upon increasing the thickness of the ZnO film reveals that the ZnO recombination barrier layer with optimum thickness at porous TiO₂/CdS interface proved to be an effective potential barrier for minimizing electron **** recombination.Zinc oxide nanoparticles (ZnO NPs) have been widely used as an inorganic electron transport layer (ETL) in quantum dot light-emitting devices (QLEDs) due to their excellent electrical properties. Here, we report the effect of ZnO NPs inorganic ETL of different particle sizes on the electrical and optical properties of QLEDs. We synthesized ZnO NPs into the size of 3 nm and 8 nm respectively and used them as an inorganic ETL of QLEDs. The particle size and crystal structure of the synthesized ZnO NPs were verified by Transmission electron microscopy (TEM) analysis and X-ray pattern analysis. The device with 8 nm ZnO NPs ETL exhibited higher efficiency than the 3 nm ZnO NPs ETL device in the single hole transport layer (HTL) QLEDs. The maximum current efficiency of 19.0 cd/A was achieved in the device with 8 nm ZnO NPs layer. We obtained the maximum current efficiency of 17.5 cd/A in 3 nm ZnO NPs device by optimizing bilayer HTL and ZnO NPs ETL.The effect of mechanical alloying (MA) on the solid state reaction of hematite and graphite system with a positive reaction heat was investigated using a mixture of elemental Fe₂O₃-C powders. The solid state reduction of hematite to Fe₃O₄ has been obviously observed after 3 hours of MA by a vibrating ball mill. A two-phase mixture of Fe₃O₄ and remaining Fe₂O₃ is obtained after 5 hours of MA. Saturation magnetization gradually increases with MA time due to the formation of Fe₃O4 and then reaches 23 emu/g after 5 hours of MA. In addition, a Fe₃O₄ single phase is obtained by MA after 3 hours and subsequently heat treated up to 700°C. X-ray diffraction result shows that the average grain size of Fe₃O₄ prepared by MA for 5 hours and heat treatment to be in the range of 92 nm. The saturation magnetization of Fe₃O₄ prepared by MA and heat treatment reaches a maximum value of 56 emu/g for 5 hours MA sample. It is also observed that the coercivity of 5 hours MA sample annealed at 700 °C is still high value of 113 Oe, suggesting that the grain growth of magnetite phase during annealing process tends to be suppressed.Semitransparent dual-metal electrodes comprising several thin layers of metals, such as Ni, Ag, Cu, and Al, were developed for designing flexible red-phosphorescent organic light-emitting diodes (OLEDs). The said diodes were fabricated by first depositing a Ni layer on four glass and polyethylene terephthalate (PET) substrates each to facilitate adhesion with glass and a flexible PET substrate. Subsequently, a conductive layer of Ni, Ag, Cu, and Al was stacked atop the first Ni layer on the four glass and PET substrates each, respectively. The proof of principles has been employed to demonstrate the performance potential via optical, physical, and electrical analyses of dual-as well as single-metal layers prior to device realization. In addition, their electrical and optical characteristics were compared against those of In-Sn-oxide-based OLEDs to demonstrate their potential with regard to application flexibility.The effects of as-deposited iron (Fe) film thickness and the hydrogen (H₂) annealing time on the spin-capability of carbon nanotube (CNT) forest have been studied. Both, the as-deposited Fe film thickness and the H₂ annealing time significantly changed the morphology of Fe nanoparticles (NPs) after annealing process during the synthesis step of spin-capable carbon nanotube (SCNT) forest. The spin capability of CNT forests depended heavily on the different thicknesses of Fe films and the H₂ annealing time. In conclusion, the spin-capability of CNT forest can be achieved by controlling the initial Fe film thickness and/or the H₂ annealing time.This paper proposes a new mechanism for detecting microscopic damage of structures based on imitating the sensory organs of spiders. Therefore, it is essential to manufacture sensors that can react sensitively to the micro deformations of structures. Numerous cracks were intentionally generated to improve the sensitivity of the proposed sensor, and an increase in the gap of the crack was observed by scanning electron microscopy (SEM) observation. Electrohydrodynamic technology is used to detect deformations in a structure of depositing Ag nano paste on a polyethylene terephtha-late (PET) substrate. https://www.selleckchem.com/products/c188-9.html Ag nano lines are also observed by SEM images. The sensor is constructed as a grid structure, by forming layers patterned horizontally and vertically. An impact tester is used to verify the mechanism for structural health monitoring using the developed sensor. The resistance changes of the sensors are applied to estimate the structure's damaged location. The intersections of the lines with varying resistance can be used to accurately detect crack initiation.
Perovskite solar cells have been attracting extensive attention because of their superior photovoltaic performances and lower costs as compared to those of prevailing photovoltaic technologies. There are four main interfaces in perovskite solar cells flourine-doped tin oxide/electron transport layer, electron transport layer/perovskite layer, perovskite layer/hole transport layer, and hole transport layer/metal electrode. Among them, the interface between the perovskite layer (general formula RPbX₃) and electron transport layer significantly affects the power conversion efficiency. In this study, a layer of TiO₂, which is the most popular metal oxides used for perovskite solar cells applications, was deposited as the electron transport layer. To enhance the perovskite solar cells performance, surface treatment was performed with TiCl₄ (80 mM). To investigate the effect of TiCl₄ treatment, ultraviolet-visible spectroscopy was performed on the perovskite film. Atomic force microscopy, X-ray diffraction, scanning electron microscopy and performance of perovskite solar cells have been also evaluated in this paper. The results indicated that the TiCl₄ treatment significantly improved the perovskite solar cells performance.In this investigation we report the formation of thin ZnO recombination barrier layer at TiO₂/CdS interface aimed for the improvement in performance of CdS sensitized solar cell. The film was deposited upon nanocrystalline mesoporous TiO₂ surface by following a simple chemical process and characterized, using UV-Visible spectroscopy, X-ray diffraction and electron dispersive X-ray measurements. The insertion of ZnO thin layer enhances the QDSC (Quantum dot sensitized solar cell) performance, contributed mainly by an increase in open circuit voltage (Voc) due to reduced electron back transfer from TiO₂ conduction band. Moreover, the analysis of photovoltaic characteristics upon increasing the thickness of the ZnO film reveals that the ZnO recombination barrier layer with optimum thickness at porous TiO₂/CdS interface proved to be an effective potential barrier for minimizing electron back recombination.Zinc oxide nanoparticles (ZnO NPs) have been widely used as an inorganic electron transport layer (ETL) in quantum dot light-emitting devices (QLEDs) due to their excellent electrical properties. Here, we report the effect of ZnO NPs inorganic ETL of different particle sizes on the electrical and optical properties of QLEDs. We synthesized ZnO NPs into the size of 3 nm and 8 nm respectively and used them as an inorganic ETL of QLEDs. The particle size and crystal structure of the synthesized ZnO NPs were verified by Transmission electron microscopy (TEM) analysis and X-ray pattern analysis. The device with 8 nm ZnO NPs ETL exhibited higher efficiency than the 3 nm ZnO NPs ETL device in the single hole transport layer (HTL) QLEDs. The maximum current efficiency of 19.0 cd/A was achieved in the device with 8 nm ZnO NPs layer. We obtained the maximum current efficiency of 17.5 cd/A in 3 nm ZnO NPs device by optimizing bilayer HTL and ZnO NPs ETL.The effect of mechanical alloying (MA) on the solid state reaction of hematite and graphite system with a positive reaction heat was investigated using a mixture of elemental Fe₂O₃-C powders. The solid state reduction of hematite to Fe₃O₄ has been obviously observed after 3 hours of MA by a vibrating ball mill. A two-phase mixture of Fe₃O₄ and remaining Fe₂O₃ is obtained after 5 hours of MA. Saturation magnetization gradually increases with MA time due to the formation of Fe₃O4 and then reaches 23 emu/g after 5 hours of MA. In addition, a Fe₃O₄ single phase is obtained by MA after 3 hours and subsequently heat treated up to 700°C. X-ray diffraction result shows that the average grain size of Fe₃O₄ prepared by MA for 5 hours and heat treatment to be in the range of 92 nm. The saturation magnetization of Fe₃O₄ prepared by MA and heat treatment reaches a maximum value of 56 emu/g for 5 hours MA sample. It is also observed that the coercivity of 5 hours MA sample annealed at 700 °C is still high value of 113 Oe, suggesting that the grain growth of magnetite phase during annealing process tends to be suppressed.Semitransparent dual-metal electrodes comprising several thin layers of metals, such as Ni, Ag, Cu, and Al, were developed for designing flexible red-phosphorescent organic light-emitting diodes (OLEDs). The said diodes were fabricated by first depositing a Ni layer on four glass and polyethylene terephthalate (PET) substrates each to facilitate adhesion with glass and a flexible PET substrate. Subsequently, a conductive layer of Ni, Ag, Cu, and Al was stacked atop the first Ni layer on the four glass and PET substrates each, respectively. The proof of principles has been employed to demonstrate the performance potential via optical, physical, and electrical analyses of dual-as well as single-metal layers prior to device realization. In addition, their electrical and optical characteristics were compared against those of In-Sn-oxide-based OLEDs to demonstrate their potential with regard to application flexibility.The effects of as-deposited iron (Fe) film thickness and the hydrogen (H₂) annealing time on the spin-capability of carbon nanotube (CNT) forest have been studied. Both, the as-deposited Fe film thickness and the H₂ annealing time significantly changed the morphology of Fe nanoparticles (NPs) after annealing process during the synthesis step of spin-capable carbon nanotube (SCNT) forest. The spin capability of CNT forests depended heavily on the different thicknesses of Fe films and the H₂ annealing time. In conclusion, the spin-capability of CNT forest can be achieved by controlling the initial Fe film thickness and/or the H₂ annealing time.This paper proposes a new mechanism for detecting microscopic damage of structures based on imitating the sensory organs of spiders. Therefore, it is essential to manufacture sensors that can react sensitively to the micro deformations of structures. Numerous cracks were intentionally generated to improve the sensitivity of the proposed sensor, and an increase in the gap of the crack was observed by scanning electron microscopy (SEM) observation. Electrohydrodynamic technology is used to detect deformations in a structure of depositing Ag nano paste on a polyethylene terephtha-late (PET) substrate. https://www.selleckchem.com/products/c188-9.html Ag nano lines are also observed by SEM images. The sensor is constructed as a grid structure, by forming layers patterned horizontally and vertically. An impact tester is used to verify the mechanism for structural health monitoring using the developed sensor. The resistance changes of the sensors are applied to estimate the structure's damaged location. The intersections of the lines with varying resistance can be used to accurately detect crack initiation.
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