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"Fluorine-doped tin oxide (FTO) is one of the conductive glasses that have strategic functions in various important applications, including dye-sensitized solar cell (DSSC). In the current work, the effects of deposition time (5, 10, 20, 30, and 40 minutes) upon the fabrication process of FTO thin film using spray pyrolysis technique with modified ultrasonic nebulizer has been studied in regard to its microstructural, optical, crystallinity, and resistivity characteristics. The variation was also performed by comparing the pure tin chloride precursor and the solution that was doped with fluor (F) at 2 wt% in order to see the doping effect on the properties of thin film. The thin films were characterized using x-ray diffraction (XRD), scanning electron microscope (SEM), ultraviolet-visible (UV-Vis) spectroscopy, and digital multimeter. On the basis of current investigation, it has been found that the best FTO was obtained through the pyrolysis technique of 20-minute deposition time, providing optical transmittance of 74%, a band gap energy (Eg) of 3.85 eV and sheet resistance (Rs) of 7.99 Ω/sq. The fabricated FTO in the present work is promising for further development as conducting glass for dye-sensitized solar cell (DSSC)."

"Fluorine-doped tin oxide (FTO) is one of the conductive glasses that have strategic functions in various important applications, including dye-sensitized solar cell (DSSC). In the current work, the effects of deposition time (5, 10, 20, 30, and 40 minutes) upon the fabrication process of FTO thin film using spray pyrolysis technique with modified ultrasonic nebulizer has been studied in regard to its microstructural, optical, crystallinity, and resistivity characteristics. The variation was also performed by comparing the pure tin chloride precursor and the solution that was doped with fluor (F) at 2 wt% in order to see the doping effect on the properties of thin film. The thin films were characterized using x-ray diffraction (XRD), scanning electron microscope (SEM), ultraviolet-visible (UV-Vis) spectroscopy, and digital multimeter. On the basis of current investigation, it has been found that the best FTO was obtained through the pyrolysis technique of 20-minute deposition time, providing optical transmittance of 74%, a band gap energy (Eg) of 3.85 eV and sheet resistance (Rs) of 7.99 ?/sq. The fabricated FTO in the present work is promising for further development as conducting glass for dye-sensitized solar cell (DSSC)."

"Transparent conducting oxide (TCO) glasses play an important role invarious technology, including dye sensitized solar cells. One of the mostcommonly used glass is indium tin oxide (ITO) glass, which is expensive.Therefore, the mainpurpose of this research was to determine if ITO glass can be replaced withfluorine-doped tin oxide (FTO) glass,which is easier and more economic to manufacture. For this purpose, a tinchloride dehydrate (SnCl2.2H2O)precursor was doped with ammoniumfluoride (NH4F) using asol-gel method and spray pyrolysis technique toinvestigate the fabrication process for conductiveglass. NH4F wasdoped at a ratio of 2 wt% in the SnCl2.2H2O precursor atvarying deposition times (10, 20, and 30 minutes) and substrate temperatures(250, 300, and 350°C). Theresults revealed that longer deposition times created thicker glass layers withreduced electrical resistivity. The highest opticaltransmittance was 75.5% and the lowest resistivitywas 3.32´10-5 Ω.cm,obtained from FTO glasssubjected to a 20-minute deposition time at deposition temperature of 300oC."

"Transparent conductive oxide (TCO) glass is one of most important components in dye-sensitized solar cell (DSSC) device. In addition to its high electrical conductivity, transparency is another important requirement that must be achieved in fabricating TCO. One TCO film is fluorine-doped tin oxide (FTO), which can be considered as the most promising substitution for indium-doped tin oxide (ITO), since the latter is very expensive. However, the fabrication techniques for TCO film need to be carefully selected; the synthesis parameters must be properly optimized to provide the desired properties. In this work, FTO glass has been fabricated by the ultrasonic spray pyrolisis technique with different precursors, i.e. tin (II) chloride dihydrate (SnCl2.2H2O) and anhydrous tin (IV) chloride (SnCl4), as well as different solvents, i.e. ethanol and methanol. For both conditions, ammonium fluoride (NH4F) was used as the doping compound. The resulting thin films were characterized by use of a scanning electron microscope (SEM), x-ray diffraction (XRD), ultraviolet-visible (UV-Vis) spectroscopy and a four-point probe test. The results of the investigation show that the highest transmittance of 88.3% and the lowest electrical resistivity of 8.44×10-5 ?.cm were obtained with the FTO glass processed with 20 minutes of spray pyrolysis deposition and 300oC substrate heating, using SnCl4 as the precursor and methanol as the solvent. It can be concluded that TCO fabrication with tin chloride precursors and ammonium fluoride doping using ultrasonic spray pyrolisis can be considered as a simple and low cost method, as well as a breakthrough in manufacturing conductive and transparent glass."

"Transparent conducting oxide (TCO) glasses play an important role in various technology, including dye sensitized solar cells. One of the most commonly used glass is indium tin oxide (ITO) glass, which is expensive. Therefore, the main purpose of this research was to determine if ITO glass can be replaced with fluorine-doped tin oxide (FTO) glass, which is easier and more economic to manufacture. For this purpose, a tin chloride dehydrate (SnCl2.2H2O) precursor was doped with ammonium fluoride (NH4F) using a sol-gel method and spray pyrolysis technique to investigate the fabrication process for conductive glass. NH4F was doped at a ratio of 2 wt% in the SnCl2.2H2O precursor at varying deposition times (10, 20, and 30 minutes) and substrate temperatures (250, 300, and 350°C). The results revealed that longer deposition times created thicker glass layers with reduced electrical resistivity. The highest optical transmittance was 75.5% and the lowest resistivity was 3.32´10-5 ?.cm, obtained from FTO glass subjected to a 20-minute deposition time at deposition temperature of 300oC."

"Nanostructured zincoxide (ZnO) was synthesized via a sonochemical method. The effect of the duration of ultrasonic irradiation in a continuous mode on the generated particles was investigated. Additionally, the effect of flowing either air or nitrogen during the sonication process was investigated. Zinc nitrate andammonia water-based solutions were selected as chemicals without the additionof other surfactants. The generated particles indicated that a wurtzitestructure of ZnO in a hexagonal phase was formed with a crystalline size that increasedas the ultrasound irradiation time increased. The morphology of the generatedZnO particles could be changed from flowerlike to needlelike structures viacontinuous ultrasound irradiation over one to two hours, resulting in increasesin the particle lengths and decreases in the particle diameters from 200 to 80nm. Photoluminescence intensity was also increased with increases in the ultrasonicirradiation times. Photoluminescence spectra were also influenced by theatmospheric environment. Two bands centered at 390 and 500 nm were generatedunder a nitrogen environment. On the other hand, a single wide band with a peakat around 430 nm was found for particles generated under an air environment. Itcan be applied for light emitting diodes (LED) or laser fabrication with acontrolled emitting band."

"We propose a simple design of 1×3 optical power splitter which uses gallium nitride (GaN) on sapphire. The design consists of widely used large cross section input rib waveguide, a rectangular multimode interference (MMI) structure, and three-branch rib waveguides. The MMI structure is selected since their attractive performances, such as compactness, low excess loss, wide bandwidth and ease to fabricate. The power splitter is designed for the third telecommunication window, i.e., l = 1.55 µm. Optimization of the geometrical structure parameters for the design is conducted theoretically utilizing 3D FD-BPM method. It is found that the power splitter exhibits excess loss of 0.46 dB and imbalanced of 0.001 dB at l = 1.55 µm for ..."

"ABSTRAKKaca konduktor memiliki fungsi strategis di berbagai aplikasi elektronik. Jenisyang menjanjikan adalah Fluorine-doped Tin Oxide (FTO). Dalam penelitian inidilakukan studi pengaruh waktu deposisi (5, 10, 20, 30, dan 40 menit) lapisan tipisFTO dengan metode spray pyrolysis menggunakan alat ultrasonic nebulizer yangtelah dimodifikasi terhadap nilai karakteristik lapisannya ditinjau dari sifat optis,kristalinitas, resistivitas, dan mikrostruktur. Variasi juga dilakukan denganmembandingkan prekursor Sn murni dan larutan yang telah didoping dengan Fsebanyak 2%wt untuk melihat pengaruh penambahan doping F pada larutanprekursor. Pengujian karakteristik lapisan dilakukan menggunakan XRD, SEM,UV-Vis spectroscopy, dan digital multimeter. Berdasarkan karakterisasi yangdilakukan diperoleh nilai terbaik untuk FTO yang dihasilkan adalah pada waktudeposisi 20 menit dengan nilai transmitansi 74%, energi band gap (Eg) 3,85 eV,dan sheet resistance (Rs) 7,99 Ω/sq.

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ABSTRACTConductive glass has strategic functions in various electronic applications. Oneof the lead is Fluorine-doped Tin Oxide (FTO). In this research, the effects ofdeposition time (5,10,20,30, and 40 minutes) for fabrication of FTO thin film uponspray pyrolysis process using modified ultrasonic nebulizer on its characteristicin terms of optical, crystalinity, resistivity and microstructure properties has beenstudied. Variation was also performed by comparing the pure Sn precursor andthe solution that has been doped with F 2%wt to see the doping effect toproperties of thin film. The thin film characterization were carried out using XRD,SEM, UV-Vis spectroscopy, and digital mutlimeter. Based on the results obtainedfor the best FTO was generated at the time of deposition is 20 minutes. Providing74% transmittance, band gap energy (Eg) 3.85 eV and sheet resistance (Rs) 7.99Ω/sq."

"Rice husk is one of themost abundant biomass wastes in Indonesia. One way to convert it into analternative source of energy is biomass gasification. This is a thermochemicalprocess which converts biomass feedstock into fuel gas or chemical feedstockgas (producer gas). The gasification type which is developed in this study isfixed bed downdraft type due to its low tar content and compatibility inmicroscale implementation. One major problem with the implemented biomassgasification reactor was ruggedness of the partial oxidation process due to theabsence of air in the reactor?s middle section, which consequently affected thepyrolysis zone. Several experiments were conducted previously using coconutshells and rice husks as solid feedstock, where an equivalence ratio (ER) of0.4 was obtained. Therefore, in order to optimize the pyrolysis zone, themodification conducted involves adding a circular air intake into the gasifier.Experiments were conducted in a pyrolysis temperature range of 300?700oCwith ER variation of 0.19, 0.24, 0.27 and 0.31. The results show that a goodquality producer gas is produced at an ER value of 0.24. This value shows apromising result because the ER value of biomass gasification standard is 0.25."

"The photocatalytic degradation of methylcyclohexane (MCH) in two phases (aqueous and vapor) was examined using modified titania that was immobilized on pumice and performed in the system of a specific condition. The photodegradation system that used a particular configuration reactor and modified catalyst could facilitate the two-phase photodegradation of MCH simultaneously. The photocatalyst was prepared by the mechanical mixing of urea and TiO2 P25 with mass ratios of 1:3 and 2:3, respectively and then calcined at 350 and 450oC. This modified photocatalyst was then immobilized on pumice and finally used for the photodegradation of MCH. The Infrared spectra studies revealed that modified titania with urea successfully incorporated a non-metal dopant within the TiO2 lattice. The catalyst that spread evenly across the surface of the pumice can be seen from Scanning Electron Microscope (SEM) characterization. The loading of 7.5% mass photocatalyst that immobilized on pumice degraded MCH in two-phases simultaneously during a 120 minute period and can be considered the optimum condition."