This research is aimed at preparing nano (WO3:Sn) thin film, so that manufacturing anode electrode for a cell electrolysis to produce hydrogen fuel, this thin film was prepared on glass substrates by using depositi...This research is aimed at preparing nano (WO3:Sn) thin film, so that manufacturing anode electrode for a cell electrolysis to produce hydrogen fuel, this thin film was prepared on glass substrates by using deposition laser pulse (LPD) technique have been studying optical properties through the spectra of absorbance and transmittance, was determine the optical energy gap was observed that the permeability increases with the wavelength found that these films have high transmittance in the visible spectral region. The allowed direct band gap was found to increase from (2.9 eV) structured characteristics was studied through the analysis of X-ray diffraction (XRD) of the prepared film for determining the yielding phase which are to set the with standard tables. Also, the sample was tested atomic force microscope to identify the roughness of prepared films surface, and has been the study of the volume of gas output voltages with change, time and current.展开更多
The Hall-Héroult process is used for alumina reduction by the use of graphite anodes even though it involves a high emission of carbon dioxide (CO2) and several other organic compounds. Proposals have been made a...The Hall-Héroult process is used for alumina reduction by the use of graphite anodes even though it involves a high emission of carbon dioxide (CO2) and several other organic compounds. Proposals have been made aiming at substituting graphite for a single-phase SnO2-based ceramic with low resistivity and chemical resistance to cryolite, which is characterized as an inconsumable anode, reducing pollutant emissions. To this end, a wide range of studies were carried out on SnO2-based ceramics modified with ZnO as a densification aid doped with the promoters of electrical conductivity such as Nb2O5, Al2O3 and Sb2O3 through a mixture of oxides and hybrid sintering in a microwave oven. The pressed pellets were sintered in a microwave oven up to 1050℃ under a constant heating rate of 10℃/min. After sintering, the density was determined by the Archimedes method, the phases were then characterized by X-ray diffraction, the microstructure and chemical composition resulting from the sintered SnO2-based ceramics were also investigated by field emission scanning electron microscopy (FE-SEM) coupled with an energy-dispersive X-ray spectroscopy (EDS) and the electrical properties were determined by the measurements of the electric field x current density. A single-phase ceramic was obtained with a relative density of above 90% and electrical resistivity of 6.1 Ω·cm at room temperature. The ceramics obtained in this study could be a potential candidate as an inconsumable anode to replace the current fused coke used in the reduction of alumina.展开更多
A two-step bonding process using a novel hybrid electrode is presented.The effects of different electrodes on bonding time,bond strength and the bonded interface are analyzed.The anodic bonding is studied using a dome...A two-step bonding process using a novel hybrid electrode is presented.The effects of different electrodes on bonding time,bond strength and the bonded interface are analyzed.The anodic bonding is studied using a domestic bonding system,which carries out a detailed analysis of the integrity of the bonded interface and the bond strength measurement.With the aid of the hybrid electrode,a bubble-free anodic bonding process could be accomplished within 15-20 min,with a shear strength in excess of 10 MPa.These results show that the proposed method has a high degree of application value,including in most wafer-level MEMS packaging.展开更多
A simple, cost effective and rapid electrochemical method has been developed for the determination of micro level ortho nitrobenzaldehyde(ONB) based on outstanding properties of modified aluminum electrode tin nanor...A simple, cost effective and rapid electrochemical method has been developed for the determination of micro level ortho nitrobenzaldehyde(ONB) based on outstanding properties of modified aluminum electrode tin nanorods/anodic aluminum oxide/aluminum(SnNR/AAO/Al) for the first time. The SnNR/AAO/Al electrode was fabricated by a second step anodization, followed by electrodeposition and its electrochemical behavior was investigated in detail. The cyclic voltammetry results indicated that the SnNR/AAO/Al electrode exhibited efficient electrocatalytic activity toward reduction of ONB in the acidic solution. It provides an appreciable improvement of reduction peak for ONB at-0.721 V.Furthermore, various kinetic parameters such as transfer electron number, transfer proton number and standard heterogeneous rate constant were calculated from the scan rates.The electrocatalytic behavior was further exploited as a sensitive detection scheme for the ONB determination by differential pulse voltammetry. Under the optimized conditions, the concentration range and detection limit are 0.1-100 μmol/L and 0.05 μmol/L, respectively,for ONB. The analytical performance of this modified sensor has been evaluated for detection of real sample such as river water and recovery of ONB was achieved all-out up to102.3% under standard addition method.展开更多
文摘This research is aimed at preparing nano (WO3:Sn) thin film, so that manufacturing anode electrode for a cell electrolysis to produce hydrogen fuel, this thin film was prepared on glass substrates by using deposition laser pulse (LPD) technique have been studying optical properties through the spectra of absorbance and transmittance, was determine the optical energy gap was observed that the permeability increases with the wavelength found that these films have high transmittance in the visible spectral region. The allowed direct band gap was found to increase from (2.9 eV) structured characteristics was studied through the analysis of X-ray diffraction (XRD) of the prepared film for determining the yielding phase which are to set the with standard tables. Also, the sample was tested atomic force microscope to identify the roughness of prepared films surface, and has been the study of the volume of gas output voltages with change, time and current.
基金the financial support granted by the Brazilian research funding institutions CNPq,CAPES and FAPESP.
文摘The Hall-Héroult process is used for alumina reduction by the use of graphite anodes even though it involves a high emission of carbon dioxide (CO2) and several other organic compounds. Proposals have been made aiming at substituting graphite for a single-phase SnO2-based ceramic with low resistivity and chemical resistance to cryolite, which is characterized as an inconsumable anode, reducing pollutant emissions. To this end, a wide range of studies were carried out on SnO2-based ceramics modified with ZnO as a densification aid doped with the promoters of electrical conductivity such as Nb2O5, Al2O3 and Sb2O3 through a mixture of oxides and hybrid sintering in a microwave oven. The pressed pellets were sintered in a microwave oven up to 1050℃ under a constant heating rate of 10℃/min. After sintering, the density was determined by the Archimedes method, the phases were then characterized by X-ray diffraction, the microstructure and chemical composition resulting from the sintered SnO2-based ceramics were also investigated by field emission scanning electron microscopy (FE-SEM) coupled with an energy-dispersive X-ray spectroscopy (EDS) and the electrical properties were determined by the measurements of the electric field x current density. A single-phase ceramic was obtained with a relative density of above 90% and electrical resistivity of 6.1 Ω·cm at room temperature. The ceramics obtained in this study could be a potential candidate as an inconsumable anode to replace the current fused coke used in the reduction of alumina.
基金supported by the Development Project of the Scientific Equipment of the Chinese Academy of Sciences(No.YZ200940)
文摘A two-step bonding process using a novel hybrid electrode is presented.The effects of different electrodes on bonding time,bond strength and the bonded interface are analyzed.The anodic bonding is studied using a domestic bonding system,which carries out a detailed analysis of the integrity of the bonded interface and the bond strength measurement.With the aid of the hybrid electrode,a bubble-free anodic bonding process could be accomplished within 15-20 min,with a shear strength in excess of 10 MPa.These results show that the proposed method has a high degree of application value,including in most wafer-level MEMS packaging.
基金CSIR (09/0810 (0021)/ 2012-EMR-I), Periyar University for providing fundUGC networking resource center for providing visiting fellowship
文摘A simple, cost effective and rapid electrochemical method has been developed for the determination of micro level ortho nitrobenzaldehyde(ONB) based on outstanding properties of modified aluminum electrode tin nanorods/anodic aluminum oxide/aluminum(SnNR/AAO/Al) for the first time. The SnNR/AAO/Al electrode was fabricated by a second step anodization, followed by electrodeposition and its electrochemical behavior was investigated in detail. The cyclic voltammetry results indicated that the SnNR/AAO/Al electrode exhibited efficient electrocatalytic activity toward reduction of ONB in the acidic solution. It provides an appreciable improvement of reduction peak for ONB at-0.721 V.Furthermore, various kinetic parameters such as transfer electron number, transfer proton number and standard heterogeneous rate constant were calculated from the scan rates.The electrocatalytic behavior was further exploited as a sensitive detection scheme for the ONB determination by differential pulse voltammetry. Under the optimized conditions, the concentration range and detection limit are 0.1-100 μmol/L and 0.05 μmol/L, respectively,for ONB. The analytical performance of this modified sensor has been evaluated for detection of real sample such as river water and recovery of ONB was achieved all-out up to102.3% under standard addition method.