• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.05a
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• pp.605-608
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• 1999

We report investigations on a Pentacene thin film as a component for active layer of Organic thin film transistors. Pentacene film was deposited by Organic Molecular Beam Deposition(OMBD) and Al electrode was deposoted by vacuum evaporation. Electrical characterization of Pentacene films were measured by the three-terminal contact resistance methods, as the results contact resistance between pentacene films and the Aluminium electrode is 5.064G$\Omega$. The Al contact with the pentacene shows the bottom contact resistance. From the current-voltage characteristics, electrical conductivity of the Pentacene film is found as ~ 10$^{-4}$ /cm. physical characterization of pentacene films were measured by UV-spectrum and Cyclic-Voltammetry method.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2008.11a
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• pp.68-68
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• 2008

There are several methods for oxide coating on metals, such as aluminum or carbon nanotubes(CNTs). Usually CVD method is introduced for various oxide coating on CNTs. Another method is electrochemical method which use potential-pH diagram for oxide coating on metal or CNTs. In this experiment, electrochemical coating parameter for oxide coating on aluminum template modified by acids and hydrogen peroxide ($H_2O_2$) were examined. SEM micrographs displayed clearly $Ni(OH)_2$ coating on template. For confirmation of electrochemical method application to EDLC electrode material fabrication, EDS spectrum was analyzed.

• Current Applied Physics
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• v.18 no.12
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• pp.1592-1599
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• 2018

The present study deals with the effect of dual cathode buffer layer (CBL) on the performance of bilayer of 4,4'-cyclohexylidenebis[N,N-bis(4-methylphenyl)benzenamine] (TAPC) and fullerene (C70)-based organic solar cell (OSC) with low donor concentration. OSC devices with CBLs have been fabricated using thermal vapor deposition technique. We report the use of lithium fluoride (LiF) and molybdenum trioxide ($MoO_3$) as CBLs. The insertion of LiF between C70 and aluminium (Al) electrode enhances the power conversion efficiency (PCE) of device from 1.89% to 2.47% but quenching of photogenerated excitons is observed at interface of C70 and LiF layers. Incorporation of $MoO_3$ between LiF and Al electrode further enhances PCE of device to 3.51%. This has also improved the material quality and device properties, by preventing the formation of gap states and diminishing exciton quenching.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.19 no.2
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• pp.161-176
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• 2021

In this study, the electrochemical behavior of Sm on the binary liquid Al-Ga cathode in the LiCl-KCl molten salt system is investigated. First, the co-reduction process of Sm(III)-Al(III), Sm(III)-Ga(III), and Sm(III)-Ga(III)-Al(III) on the W electrode (inert) were studied using cyclic voltammetry (CV), square-wave voltammetry (SWV) and open circuit potential (OCP) methods, respectively. It was identified that Sm(III) can be co-reduced with Al(III) or Ga(III) to form Al_zSm_y or Ga_xSm_y intermetallic compounds. Subsequently, the under-potential deposition of Sm(III) at the Al, Ga, and Al-Ga active cathode was performed to confirm the formation of Sm-based intermetallic compounds. The X-ray diffraction (XRD) and scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS) analyses indicated that Ga₃Sm and Ga₆Sm intermetallic compounds were formed on the Mo grid electrode (inert) during the potentiostatic electrolysis in LiCl-KCl-SmCl₃-AlCl₃-GaCl₃ melt, while only Ga₆Sm intermetallic compound was generated on the Al-Ga alloy electrode during the galvanostatic electrolysis in LiCl-KCl-SmCl₃ melt. The electrolysis results revealed that the interaction between Sm and Ga was predominant in the Al-Ga alloy electrode, with Al only acting as an additive to lower the melting point.

• Applied Chemistry for Engineering
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• v.8 no.5
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• pp.784-789
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• 1997

Aluminium solid electrolytic capacitor in which electroconducting polypyrrole(PPy) is used as an electrolyte is studied. Pyrrole(Py) is electrochemically synthesized using the etched and anodized aluminium foil electrode($Al_2O_3$) as an anode on which the thin layer of chemicalpolymerized PPy as a pre-coating layer is formed previously by chemical oxidative polymerization(CP). Investigating the effects of the polymerization conditions on the electrical characteristics of resulting capacitors, the capacitors which were obtained from the galvanostatic electrolysis of pyrrole containing sodium p-toluenesulfonate(TsONa) under the currents of $2.0{\sim}4.0mA/unit(6.5{\times}10mm)$, showed the most superior properties.

• Transactions on Electrical and Electronic Materials
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• v.17 no.1
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• pp.46-49
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• 2016

A thin film transistor (TFT) has been fabricated using the amorphous 0.5 wt% Si doped zinc-tin-oxide (a-0.5 SZTO) with different electrodes made of either aluminium (Al) or titanium/aluminium(Ti/Al). Contact resistance and total channel resistance of a-0.5SZTO TFTs have been investigated and compared using the transmission line method (TLM). We measured the total resistance of 1.0×10² Ω/cm using Ti/Al electrodes. This result is due to Ti, which is a material known for its adhesion layer. We found that the Ti/Al electrode showed better contact characteristics between the channel and electrodes compared with that made of Al only. The former showed a less contact and total resistance. We achieved high performance of the TFTs characteristic, such as Vth of 2.6 V, field effect mobility of 20.1 cm² V⁻¹s⁻¹, S.S of 0.9 Vdecade⁻¹, and on/off current ratio of 9.7×10⁶ A. It was demonstrated that the Ti/Al electrodes improved performance of TFTs due to enhanced contact resistance.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1096_1097
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• 2009

Aluminium doped zinc oxide(ZnO:Al) thin film, which is mainly used as a transparent conducting electrode in electronic devices, has many advantages compared with conventional indium tin oxide(ITO). In this paper in order to investigate the possible application of ZnO:Al thin films as a transparent conducting electrode for flexible film-typed dye sensitized solar cell (FT-DSCs), ZnO:Al and ITO thin films were prepared on the polyethylene terephthalate (PET) substrate by r. f. magnetron sputtering method. Specially one-inched FT-DSCs using either a ZnO:Al or ITO electrode were also fabricated separately under the same manufacturing conditions. Some properties of both the FT-DSCs with ZnO:Al and ITO transparent electrodes, such as conversion efficiency, fill factor, and photocurrent were measured and compared with each other. The results showed that by doping the ZnO target with 2 wt% of $Al_2O_3$, the film deposited at discharge power of 200W resulted in the minimum resistivity of $2.2\times10^{-3}\Omega/cm$ and at ransmittance of 91.7%, which are comparable with those of commercially available ITO. Two types of FT-DSCs showed nearly the same tendency of I-V characteristics and the same value of conversion efficiencies. Efficiency of FT-DSCs using ZnO:Al electrode was around 2.6% and that of fabricated FT-DSCs using ITO was 2.5%. This means that ZnO:Al thin film can be used in FT-DSCs as a transparent conducting layer.

• Analytical Science and Technology
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• v.27 no.6
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• pp.333-338
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• 2014

A simple and sensitive analytical method for fluoride in urine by ion selective electrode (ISE) method was presented. Traditional buffer for fluoride determination using ISE is acetate-based one. Researchers have pointed out some drawbacks of the buffer for fluoride ISE analysis, and some other buffers including citrate-ammonium buffer and MES buffer have been studied for accurate determination of fluoride in urine here. These buffers provided promising results in environmental field, and this author focused on overcoming the interference of co-existing aluminium. The results show that MES-CyDTA buffer gave the best recovery with accuracy of 95-97.5% and precision of 1.9-7.9% for reference sample of 1.8-7.8 mg/L fluoride in urine, with smaller amount of samples and shorter analysis time compared with the traditional method which used acetate buffer. The method was applied to field samples, and which showed urinary of $0.98{\pm}0.38mg/g$ creatinine for workers in electric cable manufacturing factory (n=15) and $0.59{\pm}0.30mg/g$ creatinine for non-exposed workers (n=12).

• Journal of Welding and Joining
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• v.21 no.2
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• pp.57-63
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• 2003

Since new types of vehicles or structures made from thin aluminum alloy are under rapid development and some products are already on the market, welding of aluminium sheet is increasing. MIG(Metal Inert Gas), MIG-Pulse, TIG(Tungsten Inert Gas) welding are the typical Ai welding. MIG welding has the advantage of high speed, but it is difficult to apply to the thin plate, because of bum-through by the high heat input and spatter. MIG-Pulse welding can weld without spatter and burn-through, but when the gap exists at the welding joint, there is quite a possibility of bum-through. TIG welding is difficult to weld at a high speed. AC Pulse welding alternates between DCEP(Direct Current Electrode Positive) and DCEN(Direct Current Electrode Negative). DCEN is higher wire melting rate than DCEP, while lower temperature of droplet than DCEP. In AC Pulse welding, far fixed welding current, wire melting rate increases as the EN ratio increases. For fixed wire feed rate, welding current decreases as the EN ratio increases. Because of these features, the temperature of droplet, the depth of penetration, the width of bead decrease and the reinforcement height increases as EN ratio increases, and these are able to weld at a high speed, lower heat input. It is the purpose of this study that design of AC pulse current waveform for MIG welding of Al sheet and estimation of output characteristic.

• Journal of the Korean Chemical Society
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• v.57 no.3
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• pp.316-321
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• 2013

Electrocoagulation (EC) technique is applied for the treatment of wastewater containing heavy metals ions such as nickle (Ni), lead (Pb) and cadmium (Cd) by using sacrificial anodes corrode to release active coagulant flocs usually aluminium or iron cations into the solution. During electrolytic reactions hydrogen gas evolve at the cathode. All the experiments were carried out in Batch mode. The tank was filled with synthetic wastewater containing heavy metals and efficiency of electro-coagulation in combination with aluminum and iron electrodes were investigated for removal of such metals. Several parameters, such as contact time, pH, electro-coagulant concentration, and current density were optimized to achieve maximum removal efficiency (%). The concentrations of heavy metals were determined by using Atomic Absorption Spectroscopy (AAS). It is found that the electro-coagulation process has potential to be utilized for the cost-effective removal of heavy metals from wastewater specially using iron electrodes in terms of high removal efficiencies and operating cost.