bluuebunny/crossref_metadata_2025 huggingface dataset:
Paramagnetic Defects Generation and Structure Change in the Porous Low-k SiOCH Films with Excess Ultraviolet and Electron-beam Curing
Authors: Tanbara Kenji , Kamigaki Yoshiaki
Published: March 2009

We have studied in detail the paramagnetic defect generated in the porous low-k SiOCH films, which is called as Tb center with the oxygen-carbon mixed back bonds. We baked the SiOCH films in vacuum at the temperature from 600oC to 1000oC, which could correspond to local temperature enhancement when UV/EB curing and Joule heating in circuits. We have found that the amount of the Tb center increased abnormally around the temperature 775oC by ESR spectroscopy. Moreover, we have observed 30%-volume shrinkage by ellipsometry and network change from cage link to ring link by FTIR spectroscopy. These phenomena might be concerned to a crush of micro holes wrapping Si-CH3 end groups. Therefore, we consider that the generation of the Tb center indicates the quality change of the porous low-k SiOCH films as for the ULSI reliability.
Evaluation of Electrochemical Characteristics of Li7La3Zr2O12 Solid Electrolyte
Authors: Kaeriyama Atsushi , Munakata Hirokazu , Kajihara Koichi , Kanamura Kiyoshi , Sato Yosuke , Yoshida Toshihiro
Published: March 2009

Electrochemical properties of Li7La3Zr2O12 (LLZ) were investigated to reveal its availability as a solid electrolyte in all-solid-state rechargeable lithium ion batteries. A pellet with a single phase of garnet-like Li7La3Zr2O12 was prepared by solid state reaction. AC impedance measurement for Li7La3Zr2O12 pellet revealed that the prepared pellet had lithium ion conductivity of 2 × 10-4 S cm-1 at room temperature. The LLZ was chemically and electrochemically stable against lithium metal, which allowed lithium metal to be utilized as anode in all-solid-state lithium batteries. The cell with Li / LLZ / Li configuration was successfully operated and showed high reversibility at the current density up to 10 microA cm-2.
Energy Balance and Stack Performance of 1 kW class PEFC
Authors: Matsushita Yoshio , Okano Jun , Okajima Keiichi
Published: March 2009

Polymer electrolyte fuel cell (PEFC) systems are expected for the use in mobile and stationary application. In this study, performance of 1 kW PEFC stack was evaluated for the reliability improvement. From the experimental results, the stack efficiency was 43.8% at 960.6 W (Higher Heating Value, HHV). From the measurement of single cell voltages, it was clarified that the difference existed on each cell at high load. It was considered that the ununiformity of MEAs and imprecise assembly of the stack affected mightily the cell voltage distribution. The improvement of the cell performance from the minimum voltage to the average level was supposed to be 10%.
Electrodeposition of Zn-Sb Thermoelectric Semiconductor Film in Ethylene Glycol Non-Aqueous Solution Containing Zn(II) and Sb(III)
Authors: Yamamoto Hiroaki , Iguchi Ryouhei , Morishita Masao
Published: March 2009

The electrodeposition of zinc-antimony thermoelectric semiconductor film was investigated in ethylene glycol (EG) solutions containing ZnCl2 and SbCl3 or antimony potassium tartrate (APT) at 393 K. In the electrodeposition using the EG-ZnCl2-SbCl3 baths, it was difficult to control the composition of the Zn-Sb films. In contrast, Zn-Sb alloy films containing 5-96 mol% Zn were obtained in the baths using APT as the antimony ion source. The composition of the electrodeposit could be controlled easily by the current density and the concentration of the bath. Zn-Sb (55.3-44.7 mol%Sb alloy film was obtained in the EG-ZnCl2-APT (85.0-14.5-0.5 mol%) bath at the current density of 100 Am-2 at 393 K, and its Seebeck coefficient was 159 μV K-1
Electrochemically Instantaneous Reduction of Conducting Polyaniline-coated Latex Particles
Authors: Chen Han , Chen Jing Y. , Aoki Koichi
Published: March 2009

A cathodic voltammetric wave was observed in an aqueous suspension of mono-dispersed, spherical polyaniline-coated polystyrene particles, whereas no anodic wave was detected. This irreversibility was common to particles with eight different diameters ranging from 0.2 to 7.5 μm. Such irreversibility cannot be found at polyaniline-coated electrodes, and thus is a property of the dispersion of polyaniline latex. The reduction current was controlled by diffusion of dispersed particles. The number of loaded aniline units per particle, determined by weight analysis, ranged from 6×106 (φ 0.2 μm) to 3×1011 (φ 7.5 μm) and was proportional to 2.9 powers of the particle diameter. The diffusioncontrolled current of the cathodic wave was proportional to 2.4 powers of the diameter. The difference in these powers, 0.5, agreed with a theoretical estimation of the diffusion-controlled current, the diffusion coefficient for which was given by the Stokes-Einstein equation.
Synthesis of Ordered Lead Dioxide Nanowires using an Electroplating Template Method
Authors: Perret Philippe G. , Brousse Thierry , Bélanger Daniel , Guay Daniel
Published: March 2009

Ordered lead dioxide nanowires were synthesized by electrodeposition through an alumina porous membrane. The reduction charge recorded on the first cyclic voltammogram in 1M H2SO4 is about three times larger for PbO2 nanowires compared to PbO2 thin film.
Effect of Ball-milling on the Physical and Electrochemical Properties of Lead Dioxide
Authors: Hamel Claudine , Brousse Thierry , Bélanger Daniel , Guay Daniel
Published: March 2009

High energy ball-milling (HEBM) of pure lead dioxide was performed in function of the milling time. HEBM leads to a transition of the initial tetragonal structure (beta-PbO2) to an orthorhombic structure (alpha-PbO2). After 1 h of milling, the PbO2 powder is composed of ~80 wt% alpha-PbO2, and this proportion does not change even if milling is prolonged. The mean crystallite size of beta-PbO2 is reduced during ball-milling. HEBM also induces morphological changes in the powder. Cyclic voltammetry in 1M H2SO4 was performed using a cavity microelectrode. The voltammograms of powder milled for different durations are similar. However, a variation of the reduction and the oxidation potential occurs when commercially available PbO2 is ball-milled.
Novel Formation of Zirconium Titanate from Multi-layered Structure of ZrO2 and TiO2 deposited by PRTCVD
Authors: Song Byung Yuin , Lee Won Gyu
Published: March 2009

PRTCVD (pulsed rapid thermal chemical vapor deposition) method has been introduced to prepare zirconium titanate (ZrTiO4) films from a multi-layered structure composed of ZrO2 and TiO2 as a primitive oxide, which allows for the preparation of a given film with different element per cycle and precise control over the thickness of the film. The feasibility of PRTCVD was evaluated and it was confirmed that a multi-layered structure composed of different primitive oxides can be easily produced by PRTCVD and transformed into a multi-component single phase oxide such as zirconium titanate by an appropriate thermal annealing process.
The Results of Applications of Energy Storage Systems for New Energy by the Demonstration Projects of NEDO
Authors: Morozumi Satoshi
Published: March 2009

This paper provides an overview of grid connection demonstration projects conducted by the New Energy and Industrial Technology Development Organization (NEDO). One important objective of NEDO's recent R&D is solving problems that arise when distributed and renewable resources are connected to power grids. The author is introducing national grid connection projects promoted by NEDO, especially focusing on energy storage applications in those projects.
Grid Stabilization by Use of an Energy Storage System for a Large-Scale PV Generation Plant
Authors: Ueda Yoshinobu , Suzuki Satoshi , Ito Takamitsu
Published: March 2009

A new energy storage system for a large-scale PV generation plant is reported in this paper. The system is applied to the demonstrative research project of New Energy and Industrial Technology Development Organization (NEDO). Leading-edge control technologies of NAS battery system contributing to grid stabilization and the power station output management system are described. Moreover, some valuable results of demonstrative tests are shown. Through the tests, it is proved that it is able to control PV output and it is possible to operate as a power station.
Development of the Flooded-type UltraBattery for Micro-HEV Applications
Authors: Furukawa Jun , Takada Toshimichi , Mangahara Toru , Lam Lan
Published: March 2009

In order to reduce the CO2 emissions and the consumption of fossil fuel, the micro (12V), medium (144V) and full (>200V) hybrid electric vehicles (HEV) will become the preferred mode of transport in the near future. The 12-V valve-regulated UltraBattery has demonstrated excellent endurance under high-rate, partial state-of-charge (HR-PSoC) operation and the Honda Insight, a medium HEV, powered by these batteries has surpassed 100,000 miles at the Millbrook Proving Ground. Micro-HEVs use one 12-V battery similar to the conventional automobile with the incorporation of idling-stop and regenerative braking. Medium-HEVs also use idling-stop and regenerative braking with the additional requirement of acceleration. Therefore, the cost increase of micro-HEVs is lower compared with that of medium-HEVs. In Europe, a 12-V valve-regulated version will be used in the micro-HEVs, while a flooded-electrolyte version for further cost reduction is preferred in Japan. Therefore, we have developed a flooded-electrolyte UltraBattery for such applications. The flooded UltraBattery is a combination of improved features from the flooded SLI battery and the UltraBattery technology. With this combination, the cycling performance of the flooded UltraBattery is 4 times longer than the improved flooded SLI battery. In this paper, the cycling performance of a flooded UltraBattery will be discussed in detail.
Rechargeable Metal Air Battery
Authors: Huang Qunjian , Cai W. , Yang Hai , Liu Jinghua , Cai Jun , Xiong Rihua , Yu Xianguo , Js Ravichandra , Shapiro Andrew P. , Hart Richard L. , Wei C.
Published: March 2009

Energy storage has become critical due to the development need in sustainable energy to address energy security and environment concern. In this report, we introduce the development of a novel rechargeable metal air (RMA) battery for energy storage applications. The unique feature of high energy density and the technical challenges for this RMA battery have been discussed. Recent progresses on technology development at GE R&D center to overcome these challenges have been elucidated.
Zinc as an Energy Carrier for Energy Conversion and Storage
Authors: Zhang Gregory X.
Published: March 2009

This paper discusses the possibility of using zinc an energy carrier for large scale energy storage. Zinc has many unique characteristics for being a good energy carrier material. In terms of four basic electrochemical properties: energy density, kinetics, stability and reversibility, zinc has an overall best balanced set of electrochemical properties in comparison with other elements in the Periodic Table. Zinc can also be supplied in a large scale as it is a relatively abundant element in earth's crest. In particular, the zinc-air system, being a very high energy density system, can have many different types of technological systems and methods of operation supported by diverse forms of zinc materials. With the rising needs for large scale energy storage in response to the rapid development in renewable energy, the concept of an energy carrier can be explored to meet these needs.
Triarylamine-functionalized Ruthenium Dyes for Efficient Dye-sensitized Solar Cells
Authors: Jin Zhengzhe , Masuda Hideki , Yamanaka Noriyo , Minami Masaki , Nakamura Tsutomu , Nishikitani Yoshinori
Published: March 2009

Triarylamine-functionalized ruthenium dyes, J5, J6, J7, and J9, were designed and synthesized as a dye-sensitizer for novel efficient dye-sensitized solar cells. DFT/TDDFT calculations performed on the four dyes gave useful information of their structural, electronic, and optical properties. These results indicated that the triarylamine ligand acts as an electron donor in a manner similar to thiocyanato ligands and Ru metal, and the TDDFT calculations predicted that the absorption in the visible region originates from electron transfer from the electron donor groups to the anchoring ligand dcbpy, through which excited electrons are directly transferred to TiO2. Under standard global AM 1.5 solar conditions, the J5, J6, J7, and J9-sensitized solar cells demonstrated overall conversion efficiencies of 5.8, 7.9, 7.8, and 7.1%, respectively. The higher efficiencies of the J6, J7, and J9 dyes compared to that of J5 are mainly explained in terms of the substituted methoxy groups providing directionality in the excited state.
Low-current Charge Properties of Large-scale Nickel Metal Hydride Batteries and Application to Photovoltaic Power Generation
Authors: Yamashita Akira , Kitano Riichi , Miyasaka Akihiro , Shodai Takahisa
Published: March 2009

A large-scale nickel metal hydride backup battery with 95-Ah nominal capacity and capable of charging even at 55 ºC was developed. This battery can be charged by a low current below 0.02 C at temperatures as high as 45 ºC. Photovoltaic power generation systems using this battery were built and field-tested.
Low Temperature Deposition of Polycrystalline Lithium Transition Metal Oxide Thin Films for Micro Batteries
Authors: Chiu Kuo-Feng , Chen C. C. , Chen P. Y. , Ho W.-H.
Published: March 2009

The choices of substrates for lithium micro batteries or thin film batteries have been limited by the high annealing temperatures, which are generally required in the fabrication of polycrystalline thin film cathodes. In this paper, a plasma assisted technique has been developed for low temperature fabrication of polycrystalline lithium transition metal oxides as thin film cathodes. The thin films were deposited by magnetron sputtering, followed by thermal annealing and plasma treatments. By applying plasma treatments, polycrystalline films of LiCoO2, LiMn2O4 and LiFePO4 have been obtained under relatively lower annealing temperatures (<400 oC). The low temperature prepared films with/without plasma treatments were compared in terms of morphologies, crystal structures and electrochemical performances. It was found that the plasma treatments lifted the discharge voltages and increased the capacity of the low temperature prepared films. The results have demonstrated the feasibility of fabricating thin film batteries on polymers or glass substrates, which generally can only endure temperatures lower than 400 oC.
Fuel Supply to Micro DMFC using Reciprocating Pump with Ultrasonic Linear Actuator
Authors: Hwang Jun Y. , Shin Kwon-Yong , Lee Sang-Ho , Lee J.-H. , Peck DongHyun , Jung Doo-Hwan , Jung ChangRyul , Jang JaeHyuk
Published: March 2009

A reciprocating pump operated by a piezoelectric linear actuator is introduced as a fuel supplying module for a DMFC. A series of experiments are conducted to characterize the performance of the present pump and effects of low reciprocating frequency pumping of fuel on output power of DMFC. The performance of the pump is studied with respect to reciprocating frequency and operating duty. The results show that the key advantage of the current pump is an ability of low frequency operation which enables high flow rectification performance and that power consumption of the pump is almost linearly proportional to the flow rate. It is also shown that the output voltage of the DMFC is stable with time even though the pumping pressure oscillates periodically
Small-Scale Energy Harvesting and Storage with Thermogalvanic Cells
Authors: Hudak Nicholas S. , Amatucci G.
Published: March 2009

Thermogalvanic cells are introduced as an alternative to thermoelectric technology for small-scale energy harvesting. Thermogalvanic cells with intercalation electrodes have energy storage capability in addition to the ability to harvest energy through thermal-to-electric conversion. This multi-functionality is a unique advantage for small-scale applications. Thermogalvanic cells also have higher voltage output and lower thermal conductivity compared to thermoelectric thermocouples. Partial molar entropy measurements of lithium-ion half cells give an indication of an electrode material's thermogalvanic voltage. Presented here are partial molar entropy measurements of LixTiS2 and LixV2O5, shown to vary greatly with the amount of lithium intercalation (x). Also shown are preliminary measurements of the voltage generated by symmetric LixTiS2 thermogalvanic cells.
Fabrication of Three-Dimensional Battery Using Ceramic Electrolyte with Honeycomb Structure by Sol-gel Process
Authors: Suzuki Yushi , Munakata Hirokazu , Kajihara Koichi , Kanamura Kiyoshi , Sato Yosuke , Yamamoto Kazuhiro , Yoshida Toshihiro
Published: March 2009

Li0.55La0.35TiO3 (LLT) with a honeycomb structure, which has micro-size-holes on both sides of a membrane, was prepared as an electrolyte for three-dimensional (3D) all-solid-state rechargeable lithium ion batteries. In this study, LiCoO2 and Li4Mn5O12 were used as cathode material and anode material, respectively, and their particles were fabricated by sol-gel method. The impregnation of active material particles mixed with the precursor sol provided a good contact between LLT and active material, which reduced an internal resistance of cell. Accordingly, the battery composed of LiCoO2 / LLT / Li4Mn5O12 was successfully operated at 1.1 V with the discharge capacity of 7.3 x A h cm-2.
Fast and Stable Charge Transfer Reaction at the Li4/3Ti5/3O4/Lithium Phosphorus Oxynitride (LIPON) Interface and its Application to All-Solid-State Thin Film Batteries
Authors: Iriyama Yasutoshi , Shimizu Daisuke , Abe T. , Sodoh Masao , Ogumi Zempachi
Published: March 2009

Electrochemical lithium insertion/extraction properties at Li4Ti5O12 thin film/lithium phosphorus oxynitride glass electrolyte (LiPON) were investigated using thin film batteries (Li/LiPON/Li4/3Ti5/3O4). The resultant battery performed very stable charge-discharge reactions for over 300 times. In addition, the rate capability under 4-40 μA cm-2 of the film battery was comparable with that of the film electrode in the 1 mol dm-3 LiClO4 dissolved in propylene carbonate solution. Using the Li4/3Ti5/3O4 thin film as negative electrode material, all-solid-state thin-film lithium-ion batteries (Li4/3Ti5/3O4/LiPON/amorphous lithium iron phosphate) were fabricated, where the Li4/3Ti5/3O4 thin film was embedded in LiPON film. This unique assembly permitted charge-discharge reactions at ca. 1.5 V also in air.
Thin Film Batteries with Li3PO4 Solid Electrolyte Fabricated by Pulsed Laser Deposition
Authors: Kuwata Naoaki , Iwagami Naoya , Matsuda Yasutaka , Tanji Yoshinari , Kawamura Junichi
Published: March 2009

High-quality Li3PO4 thin film was prepared by PLD technique as a solid electrolyte of thin film battery. The structure, ionic conductivity and electrochemical stability of the film were characterized. Ionic conductivity of the film was 4.5×10-7 Scm-1 at 25{degree sign}C with activation energy of 0.6 eV. The stability window of the film was range from 0 to 4.7 V vs. Li/Li+. Thin film battery Li/Li3PO4/LiCoO2 shows electrochemical charge/discharge peaks due to the intercalation of LiCoO2. Excellent stability and cycle performance was demonstrated.
Room-Temperature Nanocatalytic Reaction Modeling and Its Applications in Direct Energy Conversion
Authors: Hu Zhiyu , Lin Cheng-Xian (Charlie) , Sekachev Mikhail , Thundat Thomas G. , Narula Chaitanya
Published: March 2009

Nanocatalytic reactions can convert chemical energy to thermal energy at room temperature without the ignition process or the high temperature of burning. It is believed that nanostructures on the surfaces of the catalytic particles are the source of many unique properties and phenomena that are not yet fully understood. Understanding these nanoscale reaction processes is very important for developing a system to directly convert fuel to energy at the nanoscale level. In this paper we discuss a computational simulation and modeling method to study H, O, OH, and OOH dissociative chemisorption on Pt nanoclusters. In the simulation, we used a quantum-chemistry-based approach (the density function method) for the computational simulation of reactions over catalytic nanoclusters. Selected reaction mechanisms, reaction energies, and energy barriers were studied using different cluster shapes and sizes. Further discussion of how to utilize nanocatalytic reactions in nanoscale heat engines is presented with preliminary experimental data.
Metal Nanotubes and their Applications in Micro Power Sources
Authors: Srinivasan Rengaswamy , Baird Lance , Deacon Ryan
Published: March 2009

A working pre-prototype of a rechargeable Nickel Oxyhydroxide-Zinc (commonly called Nickel-Zinc or Ni-Zn) thin film cell is described. This 20-µm thick cell is able to charge and discharge more than one hundred cycles without degradation. This system is based on an aqueous electrolyte, and is far less sensitive than lithium batteries to oxygen and moisture. In addition to being ultrathin and made entirely of a polymer, the battery has no separator between the anode and the cathode. It is based on an emerging nanotechnology for populating porous polymers films with well ordered metal nanotubes (MNT). This 20-µm-thin cell forms the basis for our new and emerging Thin Film Battery Technology or TFBT.
Why Annealing Processes Affect the Optical Properties of Alq3 Films and OLEDs
Authors: Baldacchini Giuseppe , Baldacchini Tommaso , Chiacchiaretta Piero , Pode Ramchandra B. , Vincenti Maria Aurora , Wang Qian-Ming
Published: March 2009

Organic light emitting diodes, OLEDs, have been so much improved in the last two decades that they are being currently used in commercial applications for displays and lighting. Among many improving technologies, thermal treatments affect greatly their performances. In case the small molecule Alq3 is the active material, it was never understood why and how the temperature could have played such an important role. Now, we have discovered that such molecules tend to aggregate themselves in morphological states which are very much sensible to annealing processes, with the result of improved emission efficiency and lifetime of Alq3 thin films. Moreover, the latter ones are described by a four components model, FCM, which has been validated by degradation experiments during 6 years, a world record in its own.
Spectrum Change of Blue Phosphorescent Organic Light Emitting Diodes with CBP and FIrpic
Authors: Lee Chan-Jae , Yoon Do-Yeol , Moon Dae-Gyu , Choi Duck-Kyun , Han Jeong-In
Published: March 2009

In the blue phosphorescent organic light emitting devices (phOLEDs) with CBP:FIrpic, the relative intensity change of two peak, 465nm and 495nm were analyzed as degradation. As device is maintained on state, peak of 500nm is relatively increased than 465nm. It seems that these phenomena are induced by microcavity effect due to recombination region shift. As device is continuously driven, carrier blocking property of BCP is deteriorated and then recombination region is changed. Also the low triplet blocking property due to degradation of BCP let the EL spectrum to shift toward long wavelength and broaden.
Preparation and Luminescence of BaSi6N8O: Eu2+ Oxynitride Phosphor
Authors: Karkada Nagaveni , Porob Digamber , Prasanth Nammalwar K. , Setlur Anant
Published: March 2009

In this paper, we discuss synthesis and luminescence properties of Eu2+ activated alkaline-earth silicon oxynitride (BaSi6N8O) system. The Eu2+ activated material shows efficient green emission peaking around ~500nm under UV excitation with an excitation band peaking at ~300 nm. The effect of different dopant ions and its concentrations on the crystal structure and luminescence properties of the material will be discussed. The Eu2+ luminescence in this material has a much larger Stokes shift when compared to other known Eu2+ activated oxide and oxynitride hosts. We will therefore investigate the nature of the emission and excitation bands in this Eu2+ doped materials as well as the thermal quenching of these materials. These results will be compared to other oxynitride, and nitride phosphors.
Chemistry, Quantum Mechanics and the Health of Planet Earth
Authors: Barnes Norman P. , Walsh Brian
Published: March 2009

NASA is engaged in monitoring the health of Planet Earth by gathering measurements on a global scale of essential earth parameters including green house gasses, aerosols, wind velocity, and so forth. Highly specialized laser materials and designs are required to measure these parameters. Rather than using an empirical approach for laser design, a quantum mechanical model is employed. The quantum mechanical model, in concert with laser rate models, can investigate potential laser materials to determine their operating characteristics and performance level. The input for the models comes primarily through chemistry. These connections are explored.
Preparation and Biological Application of Fluorescent Poly(methyl methacrylate) Beads Hybridized with Y3Al5O12:Ce3+ Nanophosphor
Authors: Kusayama Ikumi , Asakura Ryo , Saito Daisuke , Isobe Tetsuhiko , Kurokawa Kiyoshi , Aizawa Hideki , Takagi Tomohiro , Hirayama Yosuke , Ohkubo Michio
Published: March 2009

Positively charged Y3Al5O12:Ce3+ nanoparticles and negatively charged poly(sodium 4-styrenesulfonate) are sequentially adsorbed on the surface of negatively charged poly(methyl methacrylate) beads by the layer-by-layer adsorption method to obtain the composite beads, showing green emission under the blue light excitation. These fluorescent composite beads are detected as a dot group by flowcytometry (FCM). Bovine serum albumin (BSA) immomobilized on the composite beads with green emission are mixed with anti-BSA tagged with organic red dye. The antigen-antibody reaction is detected from both green and red emissions by FCM, showing that the fluorescent composite beads can be used for detecting biological reactions.
Comparison Between MgGa2O4:Mn2+ and ZnGa2O4:Mn2+ Nanophosphors Synthesized by Glycothermal Method
Authors: Osada Morio , Takesada Masahiro , Isobe Tetsuhiko
Published: March 2009

MgGa2O4:Mn2+ (MGM) and ZnGa2O4:Mn2+ (ZGM) nanophosphors were synthesized in 1,4-butanediol by glycothermal method at 300oC for 2h. The optimum photoluminescence (PL) intensity of MGM at 0.5 mol% Mn is higher than that of ZGM at 3.0 mol% Mn. We discuss this reason from several points of view. Transmission electron microscopy reveals that the particle size of MGM is smaller than that of ZGM. The X-ray diffraction peaks of MGM are broader than those of ZGM. These results cannot explain the higher PL intensity of MGM. The electron paramagnetic resonance spectroscopy and the PL decay analysis reveal that the homogeneity of Mn2+ ions in MGM is higher than that of ZGM, resulting in the more efficient PL process for MGM. The high homogeneity of Mn2+ ions is possibly attributed to the formation of MGM from the low-crystallized glycoxide precursor with a homogeneous mixture of different metallic ions. In contrast, ZGM could be formed by the crystallization of ZnGa2O4, followed by the incorporation of Mn2+ ions into ZnGa2O4.
Synthesis of NASICON-Type Luminescent Ceramics
Authors: Koguma Ikuhiro , Oishi Kengo , Takase Satoko , Shimizu Youichi
Published: March 2009

Noble emitting phosphor powders of a stable NASICON-type structure as a host, doped with mono-, di-, and tri-valent ions as a guest, such as Na1-xCuxZr2(PO4)3, (Sr1-xSnx)1/2Zr2(PO4)3 and Tb(x+1)/3Zr2-xGax(PO4)3, were tried to synthesized by sol-gel and solid-state reaction methods. The Na1-xCuxZr2(PO4)3 powders showed blue or green photoluminescence (PL) at 410 or 540 nm under 254 nm irradiation depending on Cu+ concentration doped. The (Sr1-xSnx)1/2Zr2(PO4)3 and Tb(x+1)/3Zr2-xGax(PO4)3 powders showed strong blue PL at ca. 393 nm and strong green PL at ca. 546 nm, respectively, under 254 nm irradiation. The PL intensity was increased with increasing x in (Sr1-xSnx)1/2Zr2(PO4)3 up to x = 1.0, while that for Tb(x+1)/3Zr2-xGax(PO4)3 showed maximum at x = 0.5. Both (Sr1-xSnx)1/2Zr2(PO4)3 and Tb(x+1)/3Zr2-xGax(PO4)3 systems were not represented the concentration quenching.
Enhancement of Upconversion Luminescence from Er Doped Al2O3 Films by a Thin Metal Layer
Authors: Nakamura Toshihiro , Fujii Minoru , Usui Yoshiko , Aisaka Takeho , Hayashi Shinji
Published: March 2009

The effect of a metal layer on upconversion luminescence of Er doped Al2O3 thin films is studied. Three visible luminescence peaks, which are assigned to 2H11/2 → 4I15/2, 4S3/2 → 4I15/2, and 4F9/2 → 4I15/2 transitions of Er3+, are observed by excitation with 978.5 nm light. When a Au or Ag layer is deposited on top of the samples, the upconversion luminescence intensity is strongly enhanced. Roughness at an Al2O3-metal interface is considered to play a significant role for the enhancement. From the comparison of the enhancement factors between the upconversion PL and downconversion PL excited by 488.0 nm light, the mechanism of the PL enhancement is discussed.
Photoluminescence Properties of Nanocrystalline Diamond Grown By MPECVD in CH4/H2/N2 Ambient
Authors: LeQuan Xuan-Anh C. , Kang Weng Poo , Davidson Jim , Guo Mingsheng
Published: March 2009

We report on the photoluminescence (PL) and transmission properties of 3 diamond film samples that were lightly doped with nitrogen at varying film growth rates and compare with a 4th diamond sample that had no nitrogen fed into the reactant gas during deposition. For the given film compositions, the PL spectra were qualitatively different, showing significant influence by the presence of nitrogen. Transmission data were collected in the UV-IR range and revealed that the non-nitrogenated sample is much brighter in the IR range than the other 3 doped films. The improved brightness is attributed to a lower number of free carriers, impurities, and lattice vibrations. Raman spectroscopy is used to identify the carbon and impurity bonding types. The effect of nitrogen on electrons is discussed further in terms of field emission turn-on field performance. These results may be used to develop diamond optical systems in the short wavelength infrared range.
Photobleaching Properties of YVO4:Eu3+ Nanophosphors Synthesized by Hydrothermal Treatment
Authors: Muto Tetsuhito , Takeshita Satoru , Isobe Tetsuhiko , Sawayama Tomohiro , Niikura Seiji
Published: March 2009

When YVO4:Eu3+ nanophosphors synthesized by a low-temperature wet chemical process in the presence of citrate ions are continuously excited by UV light, the photoluminescence (PL) intensity gradually decreases. This photobleaching is accompanied with the reduction of V5+ to V4+, as confirmed by electron paramagnetic resonance spectroscopy. Hydrothermal treatment of YVO4:Eu3+ nanophosphors in the presence of PO4
3- ions produces Y(V,P)O4:Eu3+ through the partial replacement between VO4
3- and PO4
3-, and hence results in the increase in the PL intensity and the suppression of photobleaching.
The Behavior of Rare Earth Ions in Hydroxyapatite Crystal
Authors: Ohta Masatoshi , Yasuda Morihiro , Sugiyama Yasuyuki , Suzuki Yuko , Okamura Hisakazu
Published: March 2009

Rare earth ion-doped hydroxyapatite (Ln-doped HAp) samples were prepared in order to make clear the behavior of rare earth (Ln) ions living body system. Photoluminescence (PL) spectra of hydroxyapatite (HAp) had no emission peak, and that of Ln-doped HAp samples had a lot of emission peaks due to f - f electron transition of Ln3+. The emission peak intensity of fired Ln-doped HAp samples is higher than that of unfired Ln-doped HAp samples. These XRD traces of the unfired samples are similar to that of HAp, while XRD traces of the fired samples were observed that the diffraction angle of all peaks shifts to higher with an increase in the concentration of rare earth ion in each aqueous solution. These results suggest that trivalent rare earth ions are substituted for Ca2+ ion in HAp crystals.
ZnO Nano-Cauliflower Array Dye-Sensitized Solar Cells
Authors: Yamaguchi Ippei , Watanabe Mitsuru , Shinagawa Tsutomu , Chigane Masaya , Inaba Minoru , Tasaka Akimasa , Izaki Masanobu
Published: March 2009

Zinc oxide (ZnO) nano-cauliflower arrays with high-aspect-ratio hexagonal ZnO nanopillars have been prepared by using a polystyrene (PS) sphere template and an electrodeposition technique in zinc nitrate aqueous solutions. The ZnO electrodeposition is a two-step process, which is composed of electrodepositon (i) in a higher Zn(NO3)2 concentration and (ii) in a lower concentration. The structural and optical characteristics were investigated by using a field-emission scanning electron microscope and spectrofluorometer. The ZnO nano-cauliflower array is so high-quality that it emits ultraviolet light with a phton energy of 3.2 eV at room temperature due to the recombination of bound exitons. Dye-sensitized solar cells using the ZnO nano-cauliflower array as a transparent electrode have been fabricated and an energy conversion efficiency of 0.15% was obtained.
A Novel Process for Etching Modulated Profiles
Authors: Sporer Ryan William , Landau Uziel , Kuo Hong-Hsiang (Harry) , Wang Yar-Ming
Published: March 2009

A novel process for spot repair of damaged anodized aluminum panels is described. The process is based on etching the aluminum oxide layer using special fixtures that provide controlled, gradual transitions of the etched profile, enabling the fabrication of "borderline"-free repaired regions. The process does not require the application of etching masks. The profile of the etched region is solely controlled by the geometry of the specially developed etching fixture. Excellent agreement has been noted between experimental results and transport controlled models that predict the etching profile.
Electrodeposition of Iron in Aqueous Alkaline Solution: An Alternative to Carbothermic Reduction
Authors: Yuan Boyan , Haarberg Geir Martin
Published: March 2009

In our previous studies, we have demonstrated that the electrodeposition of iron from iron oxide particles suspended in concentrated sodium hydroxide mixture could be an efficient and cost-effective process for iron production with significantly reduced carbon dioxide emissions. Electrodeposition of compact metal deposits is of significant technical importance. In this paper, we present the different microstructures of iron deposited on rotating graphite substrate under different experimental conditions. These textures can be classified as three types: powdery deposit with a needle shape; compact deposit with a columnar structure of flattened layer-by-layer crystal growth; fairly dense deposit with compact pyramid layers. Processes involved in the electrochemical formation of the three dimensional bulk deposits, i.e., the mass transfer and electro-reduction of the iron oxide particles to iron metal atoms, and the subsequent nucleation and crystal growth on the graphite-cathode surface were discussed with respect to their influences on the microstructure of the deposited iron metal.
Electrochemical Gold Deposition from Non-Toxic Electrolytes
Authors: Roy S.
Published: March 2009

An additive free electrolyte containing aurochloric acid, sodium sulphite and sodium thiosulphate has been used to electrodeposit gold. The electrolyte is stable at near neutral conditions and was stable on storage after formulation. Laboratory scale experiments showed that the electrolyte was compatible with positive photoresists. UV-Vis spectroscopy and cyclic voltammetry indicate that gold is discharged from a thiosulphate ligand. Industrial scale piloting experiments showed that high quality gold could be deposited from the electrolyte.
The Recovery of Copper and Tin from Waste Tin Stripping Solution Part II: Kinetic Analysis
Authors: Roy S. , Buckle Rachel
Published: March 2009

In a previous work we had carried out a thermodynamic analysis to determine if copper can be recovered from a tin stripping process (1). In this paper we present a kinetic analysis to determine the current efficiency for copper electrodeposition from a tin strip waste solution. We have performed electrochemical stripping analysis to from simulated and real waste tin strip solutions. Copper is electrodeposited from solutions containing only copper and nitric acid, copper and nitric acid with ferric and tin ions, or waste from tin-strip processes. Our results show that copper can be recovered at reasonably high current efficiency from solutions containing nitrate ions. The presence of ferric ions, however, reduces current efficiency significantly.
Photocatalytic Film Prepared by Electrophoretic Sol-Gel Deposition - Challenges for the Visible Light Activity
Authors: Yoshihara Sachio
Published: March 2009

Electrophoretic Sol-Gel Deposition was introduced to immobilize the TiO2 photocatalysis. The raw solution for the deposition consisted of Titanium tetra-isopropoxide, isopropyl alcohol and water. For the purpose of hydrolysis concentrated Nitric acid was poured to this solution. Finally thus prepared solution was diluted at a constant ratio. The electrodeposition was performed by constant voltage mode. Working electrode, cathode was a Stainless Steel. Applied voltage between the cathode and anode was varied from 10V to 40V. The deposition could be terminated within few mins. Photocatalytic activity was evaluated by the decomposition rate for acetaldehyde gas. Thus prepared coated films showed quite high photocatalytic activities without successive heat treatment. Moreover the photocatalytic activity for visible light was confirmed by Boron incorporation into the bath. And similar photocatalytic activity for visible light was confirmed in the case of the prepared film on active carbon substrate.
Controlling Scratching in Cu Chemical-Mechanical Planarization (CuCMP)
Authors: Eusner Thor , Saka Nannaji , Chun Jung-Hoon , Armini Silvia , Moinpour Mansour , Fischer Paul
Published: March 2009

In the manufacture of advanced semiconductor devices, undesirable scratches are produced during such fine-scale material removal processes as chemical-mechanical planarization (CMP). In this paper, the upper-bound loads for scratching in CMP at single-particle contacts are estimated and validated by AFM experiments on thin, homogeneous coatings. Additionally, the upper limits for the scratch width and depth are estimated and validated by polishing experiments. For a Cu surface polished on a Rohm and Haas IC1000 pad with Al2O3 or SiO2 abrasives the maximum scratch width is about one-half of the abrasive particle diameter.
The Effect of a Threshold Failure Time on Electromigration Behavior of Copper Interconnects
Authors: Filippi Ronald G. , Lloyd Jim , Wang Ping-Chuan , Brendler Andrew , Poulin James , Demarest J. , Redder Bruce
Published: March 2009

Electromigration results are described for a Dual Damascene structure with copper metallization and a low-k dielectric material. The failure times follow a three-parameter lognormal behavior, with a threshold failure time needed to accurately represent the entire failure distribution. It is found that the threshold failure time scales differently with current density than the median time to failure, which has significant implications for projecting lifetimes obtained at stress conditions back to chip operating conditions. The observed current density dependency suggests that there are two components of the electromigration lifetime, one controlled by void nucleation and the other controlled by void growth.
Blech Effect in Copper Interconnects, Its Applications and Design Considerations
Authors: Wang Ping-Chuan , Filippi Ronald G. , Christiansen Cathryn , Li Baozhen , Ding Hanyi
Published: March 2009

Electromigration results are compared for Cu interconnects with either SiO2 or low-k organic spin-on layer as the dielectrics, where its dependence on the dielectric material is insignificant over the range of experimental conditions. Considering the difference in mechanical modulus between the two dielectric materials, the Blech effect in electromigration is likely to be limited by the delamination between the dielectrics and capping layer. Finally, design considerations based on finite element modeling will be discussed, including the benefit in allowed current density from the Blech effect, particularly for high temperature applications.
Solder Bump Electromigration and CPI Challenges in Low-k Devices
Authors: Susko Robin , Daubenspeck Timothy , Wassick Thomas , Sullivan Timothy , Sauter Wolfgang , Cincotta John
Published: March 2009

Understanding and managing both chip-to-package interaction (CPI) and solder bump electromigration (EM) in new designs is becoming an increasing challenge for flip chip plastic ball grid array (FCPBGA) packaging. Requirements for state-of-the-art device technologies drive smaller features, higher power and RoHS compliance (Pb-free product). It will be shown that the optimal attributes for Pb-free solder bump EM performance often are diametrically opposed to the design parameters that improve CPI robustness in structures comprised of low-k dielectric materials.
The Effect of Al Substitution in LiNi1/3Co1/3Mn1/3O2 Cathode Materials
Authors: Johannes Michelle D. , Pillay Devina
Published: March 2009

Using density functional theory, we investigate the effect of exchanging Al for transition metal cations in the cathode material, LiNi1/3Co1/3Mn1/3O2 (NCM). We first detail the development of the cationic energy bands that determine the electrochemically active ion at various Li concentrations. We find that throughout most of the voltage range, electrons are drawn from Ni-derived bands. We find that substituting Al for Mn allows the higher voltage Co redox couple to be accessed earlier in the charge cycle. Our theoretical result indicates that Al doping could prove useful for raising the voltage of NCM cathodes.
First Principles Computations Studies: Structural and Electrochemical Behavior of Layered Cathode Materials
Authors: Saavedra-Arias Jose J. , Thomas Reji , Karan Naba K. , Ishikawa Yasuyuki , Katiyar Ram S.
Published: March 2009

First principle calculations and alloy metal method were used for understanding the behavior of the compounds that can be used as a cathode material for lithium ion battery. From calculations we found that LiNi0.8Co0.1Mn0.1O2, is a promising material. The experimental results showed a single phase material, without any structural transformation during the first cycle of the electrochemical process.
Characterization and Electrochemical Properties of Li2Cu0.5Ni0.4M0.1O2 Lithium-ion Battery Cathodes
Authors: Love Corey T. , Johannes Michelle D. , Stux Arnold M. , Swider-Lyons Karen
Published: March 2009

Doped lithium copper-nickel mixed-metal oxides are prepared and studied as cathode materials for secondary Li-ion batteries. The compounds, Li2Cu0.5Ni0.4M0.1O2 (where M = Al, Ga), are made using solid state and micro-emulsion synthesis techniques. All compounds have a body-centered orthorhombic (Immm) crystal structure. The undoped compound has an initial discharge capacity of 270 mAh/g but exhibits poor capacity retention with cycling. The Al- and Ga-doped compounds made by solid-state synthesis have a higher discharge capacity than those made by micro-emulsion. Micro-emulsion processed compounds exhibit better cycleability and capacity retention upon charge/discharge suggesting a more stable crystal structure. Gallium doping improved the structural stability resulting in lowered irreversible capacity loss. Two reversible reaction mechanisms, lithium intercalation/de-intercalation and a displacement reaction are suggested to occur in the Li2Cu0.5Ni0.4M0.1O2 system.
Microwave-Irradiated Solvothermal Synthesis of LiFePO4 Nanorods and their Nanocomposites for Lithium Ion Batteries
Authors: Murugan A. Vadivel , Muraliganth T. , Manthiram A.
Published: March 2009

LiFePO4 nanorods have been synthesized by a rapid microwave-solvothermal approach within 5 minutes at temperatures as low as 300 oC without requiring any inert atmosphere or post annealing at elevated temperatures in reducing gas atmospheres. The resulting LiFePO4 nanorods have subsequently been encapsulated within (i) a mixed electronically and ionically conducting p-toluene sulphonic acid (p-TSA) doped poly(3,4-ethylenedioxythiophene) (PEDOT) and (ii) multiwalled carbon nanotubes (MWCNTs) at ambient-temperatures to obtain a nanocomposite. These LiFePO4-PEDOT and LiFePO4-MWCNT nanocomposites offer discharge capacities of, respectively, 166 and 161 mAh/g, which are close to the theoretical value of 170 mAh/g, with excellent capacity retention and rate capability.
Electrochemical Properties of Foliated Graphite / Titanate Nanosheets Composites as an Anode Material for Li-ion Secondary Batteries
Authors: Watanabe Daichi , Suzuki Shinya , Miyayama Masaru
Published: March 2009

A novel anode material was prepared by a co-restacking of foliated graphite and titanate nanosheets. Foliated graphite / titanate nanosheets composites with 63wt% of foliated graphite exhibited a charge capacity of 820 mAh/g at the 20th cycle at a current density of 100 mA/g. Even at a high current density of 2000 mA/g, the composites retained 43% of the charge capacity at a current density of 100 mA/g. Foliated graphite / titanate nanosheets composites exhibited both a good cycling durability with a high specific capacity and a high-rate capability.
Laminated Thin Films of Titanate Nanosheets Obtained by Electrophoretic Deposition for High-Rate Capable Electrodes of Li-ion Batteries
Authors: Suzuki Shinya , Yano Masato , Miyayama Masaru
Published: March 2009

Thin films of titanate were prepared by electrophoretic deposition (EPD) of a colloidal suspension of nanosheets, and their lithium intercalation properties were examined. Flat and dense films with relative density of approximately 95 % were obtained by EPD. Thickness of the obtained film increased approximately in proportion to the increase in deposition time. The reversible capacity for the obtained film was approximately 210 mA h g-1. The obtained thin films showed high capacity retention of more than 50 % even at a fast sweep rate of 30 mV sec-1. Thin films of titanate nanosheets prepared by EPD exhibited a relatively large capacity and excellent high-rate capability.
Three-Step Synthetic Methodology to a New Family of Polylithium Salts for Lithium-ion Batteries
Authors: Chakrabarti Amartya , Filler Robert , Mandal Braja K.
Published: March 2009

We report a convenient three-step synthetic route to access a new class of low lattice energy polylithium (PLI) salts, which consist of a 3D core (scaffold) substituted with three to four lithium sulfonimide moieties. The salts were characterized by 1H-NMR, FTIR and elemental analysis. Thermal stability of the salts was tested using thermogravimetric analysis. Cyclic voltammetry studies of these salts were conducted in 1:1 weight ratio of ethylene carbonate (EC) dimethyl carbonate (DMC) solvent mixture. All the salts exhibited excellent thermal and reasonable oxidative stability. PLI-1 showed the best salt, with ambient temperature ionic conductivity of 4.3x10-3 S/cm at 0.30 M concentration in 1:1 w/w EC/DMC and a cationic transference number of 0.59.
Thermal Behavior of Lithium-Ion Cells by Adiabatic Calorimetry: One of the Selection Criteria for All Applications of Storage
Authors: Wu Yi-Fan , Brun-Buisson David , Genies Sylvie , Mattera Florence , Merten Jens
Published: March 2009

Accelerating rate colorimeter (ARC) is used to analyze the thermal properties of two types Li-ion based commercial batteries, LiCoO2/C and LiFePO4/C, with various states of charge (SOC) and aging conditions. Also, with electrochemical impedance spectroscopy (EIS) and battery performance under different stages, the internal situations of the batteries would be better understood to explain the behaviors on thermal properties. Results showed LiFePO4/C based battery possesses better thermal equity than that of LiCoO2/C type. The effect of aging would somehow prolong the exothermic behaviors of batteries may due to the extra formation of solid electrolyte inter-phase, which is shown on the impedance increase from SEI and capacity loss.