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A complete account on the optimized critical parameters in the synthesis condition of crystalline carbon nanotubes (CNTs) based on chemical vapor disposition (CVD) is presented. The degree of crystallinity in the synthesized carbon nanotubes was studied to investigate the correlation of the effective parameters involved with the structural improvements of CNTs. Camphor oil, which is readily obtained from renewable feedstock, is an ideal "green" biosource for the production of CNTs. Raman spectroscopy has been used to explain the defects of graphitic sheets in the growth of CNTs. The growth rate, which was calculated using the distribution length of the tubes, suggesting active catalyst, which controls the uniformity and alignment of the CNTs. The results indicate that the crystalline graphitic sheets increase progressively in the highest concentration of catalyst, while dens of carbon nanotubes is directly influenced by the ratio of catalyst to the precursor. Furthermore, a higher degree of crystalline perfection can be achieved in a naturalized cooling method, followed by high annealing temperature for developing the graphitic domains, which still continues in the annealing process.

Hydrophilic nano-carbon particle solution has been prepared up to 1.2 wt%-C by anodic electro-oxidation of graphite in water. It is composed of mellitic acid and graphite. A new application to metal ion trapping has been tested using a mineral water. Ca ions have been well trapped by nano-carbon particles, however, Mg ions did not been so well.

A new type of counter electrode (CE), composed of hydrophilic carbon (HC) particle and TiO2 colloid (HC/TiO2), was successfully prepared using doctor blade technique on fluorine-doped tin oxide substrate for dye-sensitized solar cell (DSSC). Properties of HC/TiO2 CE, including crystal structure, surface morphology, roughness, conductivity, and catalytic activity, were analyzed. Results showed that a HC/TiO2 CE with an average thickness of 1 µm contributed to high surface roughness. Cyclic voltammetry further revealed that HC/TiO2 CE displayed good catalytic activity similar to that of Pt electrode, which is mainly attributed to an addition of TiO2 in the electrode. DSSC was fabricated with HC/TiO2 CE. Under one sun illumination (AM 1.5, P in of 100 mWcm−2), the device exhibited an energy conversion efficiency of 1.9 %, which is comparable to 3.6 % of the cell with Pt electrode under the same experimental conditions. These findings suggest that HC/TiO2 CE is a promising alternative CE for low-cost DSSCs.

Carbon nanotube (CNT)-based electrochemical biosensors are used to determine the concentration of analytes by measuring mass, heat, or oxygen. CNTs, as an immobilizing platform of biomaterials, play an important role in enhancing the electron transfer mechanism of a biosensor. The large surface area and optimum aspect ratio (length to thickness) of CNTs maximize the amount of immobilized biomaterials on the surface. In this study, various aspect ratios of CNTs are reported, based on the alteration of growth mechanisms using CVD. The growth-dependent and -independent parameters of the CNT arrays are studied as functions of the synthesis method.

The unique properties of Carbon nanotubes (CNTs) were determined from 15 years' worth of scientific investigation in the context of multiple applications. Here, we report the effect of time dependent temperature on camphor oil within 500–1150°C of different vaporization times. According to the results, the CNTs growth rate was increased abruptly by increasing vaporization time. This process was conducted in similar conditions by optimizing the temperature to up to 900°C. FESEM images indicate that the highest catalytic activity was achieved at 180°C and 800°C of first and second furnace, respectively, directing the experiment in growing purified CNT to up to 111 µm in length during the 30 minutes reaction time. It was also gleaned from the results that at the lower vaporization time and temperature, the catalyst-support interaction is not completed to allow the metal particles to partake in the deposition process, but in the optimized vaporization process, MWCNTs can be selectively grown as a function of ...

In this present work, crystalline growth conditions of oriented carbon nanotubes based on chemical vapor deposition (CVD) were optimized. The crystallinity and degree of alignment of the grown carbon nanotubes (CNTs) were characterized by field emission scanning electron microscopy, transmission electron microscopy, and Raman spectroscopy. The effects of four variables, namely, deposition time, deposition temperature, annealing process, and concentration of the precursor on the crystallinity of the CNTs, were explored. Furthermore, the correlation of parameters with the growth mechanism was examined using response surface methodology in an attempt to determine the complex interactions between the variables. A total of 30 runs, including predicting and consolidation runs to confirm the results, were required for screening the effect of the parameters on the growth of the CNTs. On the basis of the investigated model, it was found that the crystallinity of the CNTs grown by the CVD method can be controlled via restriction of the effective parameters. (Graph Presented).

The hydrophilic carbon nanoparticles have been produced from synthetic graphite blocks by the electrochemical oxidation method in pure water. The resulting electrolyzed solution contains colloidal carbon nanoparticles (mean diameter is ca. 400 nm) and shows the pH value of around 2.5. The colloidal state of the solution is maintained more than a several years. After evaporation of water from the solution, carbon powders are obtained, which show a high solubility to water, namely the powder is hydrophilic. The electrolyzed solution containing carbon nanoparticles directly used as the electrical conductivity enhancer for the restoring the deteriorated lead-acid batteries by electrochemical method. The hydrophilic carbon nanoparticles were used as the environmental friendly solid-lubricant for the mechanical cutting coolants. In the case of aqueous coolants, the oily substances are used in the emulsion state in usual. By using the hydrophilic carbon nanoparticle suspension, no surfactants and no oily substances are required to maintain the suspension state. However, the cutting coolants are used in the pH values of alkaline state near 10, so the hydrophilic carbon nanoparticle solution has been neutralized by alkaline substances such as alkanolamines. In the case of oily cutting fluids for heavy duties, carbon mamo-particle powders are used after neutralized by basic barium dinonylnaphthalenesulfonate. The aqueous solutions of hydrophilic carbon nanoparticles exhibit the ability of sanitization effects to the cutting fluids and prolong the life times of them.

In this contribution, vertically aligned carbon nanotubes were synthesized by chemical vapor deposition (CVD). The effects of intrinsic disorders constructed by mobile surface contaminants on the structural perfection of carbon nanotubes (CNTs) were investigated. The results indicated a complete picture on the effect of the involved parameters on the lattice defects of modulated CNTs based on the cooling step. Raman scattering showed that the different cooling methods of the CVD preforms altered the bound complex defects of the structure of the CNTs. Moreover, an array of CNTs was removed from the silicon substrate by applying the neutralized cooling method on the CVD, while the vertical and parallel orientations were retained. The FESEM images, coupled with Raman spectroscopy results, confirm the morphological improvements of the growth CNTs based on the neutralized cooling method.

Quantum dot-sensitized solar cells (QDSSCs) are renowned energy devices known for their distinct qualities, including (i) the ability to harvest sunlight that generates multiple electron–hole pairs, (ii) simplicity in fabrication, and (iii) low cost. The power conversion efficiency (η) rates of many QDSSCs are lower than those of dye-sensitized solar cells, reaching a maximum of 12% as a result of narrow absorption ranges and of the charge recombination occurring at the QD– and TiO2–electrolyte interfaces. New types of sensitizers are necessary to be developed to further increase the η of QDSSCs. Semiconductor QDs are the most applicable material for photosensitization because of their high absorption and the obtained emission spectra that can be manipulated by varying dot sizes. This paper presents an overview of recent studies on QDSSC photosensitization and provides suggestions to improve QDSSCs by explicitly comparing different sensitizers. Particular focus is directed on the behavior of several important types of semiconductor nanomaterials (sensitizers such as CdS, Ag2S, CdSe, CdTe, CdHgTe, InAs, and PbS) and other nanomaterials that are TiO2, ZnO, and carbon-based species. These materials are developed to enhance the electron transfer efficiency of QDSSCs. Understanding the mechanism of various photosensitization processes can provide design guidelines for future successful applications.

Among the wide range of renewable energy sources, the ever-increasing demand for electricity storage represents an emerging challenge. Utilizing carbon nanotubes (CNTs) for energy storage is closely being scrutinized due to the promising performance on top of their extraordinary features. In this work, well-aligned multilayer carbon nanotubes were successfully synthesized on a porous silicon (PSi) substrate in a fast process using renewable natural essential oil via chemical vapor deposition (CVD). Considering the influx of vaporized multilayer vertical carbon nanotubes (MVCNTs) to the PSi, the diameter distribution increased as the flow rate decreased in the reactor. Raman spectroscopy results indicated that the crystalline quality of the carbon nanotubes structure exhibits no major variation despite changes in the flow rate. Fourier transform infrared (FT-IR) spectra confirmed the hexagonal structure of the carbon nanotubes because of the presence of a peak corresponding to the carbon double bond. Field emission scanning electron microscopy (FESEM) images showed multilayer nanotubes, each with different diameters with long and straight multiwall tubes. Moreover, the temperature programmed desorption (TPD) method has been used to analyze the hydrogen storage properties of MVCNTs, which indicates that hydrogen adsorption sites exist on the synthesized multilayer CNTs.

We have produced nanocarbon suspension in pure water, which is named as Nanocaloid®, by a simple DC electrolysis from a synthetic graphite plates as anodes and SUS plates as cathodes in purified water at room temperature. The amount of carbon nanoparticles was monitored by the conductivity and pH value of the electrolyte solution, and also by a simple gravimetric way after drying the solution. If the current density increases, the diameter of the carbon particles becomes larger and the amount of precipitates becomes also large. It takes about six weeks to obtain about 0.4 wt% carbon suspension solution under the normal electrolysis conditions. Characterization of Nanocaloid®has been conducted to show unique properties and promising epoch-making applications such as solid lubricants for non-oily cutting fluids and conductive agents for reuse of deteriorated Pb-acid batteries. The performance of nanocarbon particles in oil lubricants in addition to the preparation will be reported.

Carbon nanotubes (CNTs) are potentially ideal tips for atomic force microscopy (AFM) due to the robust mechanical properties, nano scale diameter and also their ability to be functionalized by chemical and biological components at the tip ends. This contribution develops the idea of using CNTs as an AFM tip in computational analysis of the biological cell’s. Finite element analysis employed for each section and displacement of the nodes located in the contact area was monitored by using an output database (ODB). This reliable integration of CNT-AFM tip process provides a new class of high performance nanoprobes for single biological cell analysis.

According to the unique properties of Carbon nanotubes (CNTs), they have been under scientific investigation for more than fifteen years in different applications. Here we reported the effect of temperature on camphor in a wide range of 500–1150 ˚C. The results indicate that camphor did not decompose below 500 ˚C but very short-length tubes emerged from the silicon substrate at 550 ˚C which is suggesting that the catalyst activity. According to the results, the CNT growth rate was abruptly increased at 600 ˚C. This process was done on the same condition by optimizing the temperature up to 900 ˚C. FESEM images indicate the highest catalyst activity at 850 ˚C which direct the experiment to grow purified CNT up to 3 µm in the length. This result suggests that, at low temperatures, the catalyst–support interaction is strong enough not to let the metal particles to involve in deposition process, but at 850 ˚C MWCNTs and SWCNTs can be selectively grown as a function of CVD temperature. The optimum deposition ti...

The remarkable properties of carbon nanotubes (CNTs) make them attractive for biosensor applications, especially for medical detecting devices. In this paper, we describe a process to grow high oriented ratio CNT arrays to improve the electrical properties of the devices based on CNTs. Chemical vapor deposition (CVD) was used to grow highly oriented CNT using camphor as the carbon source, and argon and hydrogen as carrier gases to grow perpendicular CNTs on the surface of the silicon substrate in presence of ferrocene as a metallic catalyst. Images were revealed by FESEM indicates that the formation mechanism of oriented CNTs with high morphological purity nanotubes, which is depends significantly on deposition time and applied temperature to the furnaces. This method might be an effective method to produce oriented MWCNT in different length.

Various aspect ratios of CNTs reported based on alteration of annealing temperature using thermal-chemical vapor deposition (TCVD) method. Also the growth dependent and independent parameters of the carbon nanotube (CNTs) array were studied as a function of synthesis method. The FESEM images indicate that the nanotubes are approximately perpendicular to the surface of the silicon substrate and form carbon nanotubes in different aspect ratios according to the applied annealing temperature. Furthermore, due to the optimized results it can be observed that, the mechanism of the CNTs growth is still present in the annealing step as well as deposition process and the most CNTs with crystalline aspect, produced in the annealing temperature, which was optimized at 700 - 900 ˚C. This result demonstrates that the growth rate, mass production, diameter, density, and crystallinity of CNT can be controlled by the annealing temperature.

Observations of the surface layer and the atmospheric boundary layer (ABL) were collected as part of the Lower Atmosphere and Precipitation Study (LAPS), which investigated the relationship between the surface conditions and the ABL processes. The LAPS was part of the Core Research for Evolutional Science and Technology (CREST) program, under the auspices of the Japan Science and Technology Agency (JST). Observations began in August 2003 over a flat surface region in mid-latitude China at 32-55 °N, 116-78 °E. Observations before, during, and after the Meiyu season in China provided data for surface conditions varying from relatively dry to moist. Preliminary analysis of the surface and the ABL observations shows relationships between the surface fluxes and the ABL structure. ABL depth was enhanced by sensible heat flux. Fluctuations in the ABL depth corresponded to plume-like wind structures within the ABL. Day-to-day variability in ABL depth was controlled mainly by buoyancy flux over the surface during dry periods. It was also affected by vertical motion at the top of the ABL, especially during wet periods.

Dye-sensitized solar cells (DSSCs) serve as low-costing alternatives to silicon solar cells because of their low material and fabrication costs. Usually, they utilize Pt as the counter electrode (CE) to catalyze the iodine redox couple and to complete the electric circuit. Given that Pt is a rare and expensive metal, various carbon materials have been intensively investigated because of their low costs, high surface areas, excellent electrochemical stabilities, reasonable electrochemical activities, and high corrosion resistances. In this feature article, we provide an overview of recent studies on the electrochemical properties and photovoltaic performances of carbon-based CEs (e.g., activated carbon, nanosized carbon, carbon black, graphene, graphite, carbon nanotubes, and composite carbon). We focus on scientific challenges associated with each material and highlight recent advances achieved in overcoming these obstacles. Finally, we discuss possible future directions for this field of research aimed at obtaining highly efficient DSSCs.

Most of the additives or activators used today for the negative electrode of lead-acid batteries are fine power of solid materials such as barium sulphate, lignin and carbon black. They are generally called as expander. We found that organic compounds soluble in the acid electrolyte are very effective in order to extend the cycle life and improve the discharge capacity. This paper describes the recent improvements and the working mechanism for the soluble organic activators.

We have been investigating the prolongation of the life-time of lead-acid batteries in the view point of environmental aspects and material resources. Since 1997, we have been working on the activators for lead-acid batteries. We developed various activators using composite organic polymers with solid powder, organic polymers, etc. The effects of prolongation of life-time have been compared between our activators and the other commercially available additives, using actual 6 V batteries for motor cycles. The change in the internal resistance of batteries has been measured during discharge-charge cycles to clarify the deteriorating mechanism. Organic polymer P is useful for prolongation of the life-times of lead-acid batteries if it is used with a suitable amount. The solution of electrolyzed carbon particles with 2.00 ms/cm is also effective for enhancement of the battery performance, and more effective if it is used together with a small amount of organic polymer. The internal resistance of the battery becomes a good index of deterioration of the battery.

We investigated the relationships among the deposition potential, the electric properties, and the thermoelectric properties of Bi2Te3 films electrodeposited from a solution containing 1.00mM TeO2 and 0.86mM Bi-EDTA complex. From the results of the Hall-effect measurements, the films formed at >−0.27V vs Ag∕AgCl were Te-rich n-Bi2Te3, and the carrier concentration increased with more negative deposition potential. The films formed at

The In-site of Ba2In2O5 with Brownmillerite structure was partially substituted for Ce4+ ions in order to examine the doping effect on the order-disorder transition. Ba2In2 − xCexO5 + x/2 (x = 0.1, 0.2, 0.3, 0.5, 1.0, and 1.5) were prepared by solid state reaction. X-Ray diffraction analyses of these powder samples demonstrated that Ba2In2 − xCexO5 + x/2 (x = 0.1 and 0.2) possesses Brownmillerite structure. With increasing content of Ce4+ ion the crystal system of Ba2In2 − xCexO5 + x/2 (x = 0.3, 0.5, and 1.0) changed to cubic perovskite structure above the order-disorder transition temperature of Ba2In2O5. Arrhenius plots of the electrical conductivities of Ba2In2 − xCexO5 + x/2 (x = 0.2, 0.3, and 1.0) exhibited no discontinuity. These compounds had high transference numbers of oxide ion above 973 k.

Solid solutions of BaLaIn2O5.5 and BaLaInMO5.5 that formed by partial replacement of In by Sc and Ga have a cubic perovskite structure. The Sc3+- and Ga3+-doped compounds, which had almost the same electrical conductivities, exhibited lower conductivities than the parent compound BaLaIn2O5.5 in the temperature range from 573 to 1273K. The Ga compound showed a transference number, ti, of unity at both high and low oxygen partial pressures in the temperature range from 973 to 1273K. As for the Sc compound kept at 973-1273K, a ti of nearly unity was observed at low oxygen partial pressure, while the ti was slightly lower than unity at high oxygen partial pressures at higher temperatures. The In compound had a ti of almost unity at high oxygen partial pressure, whereas the number decreased to a value less than 0.9 at low partial pressures of oxygen. The stepwise increase in the Sc content from 0.1 to 1.0 in BaLaIn2-xScxO5.5 caused a monotonic decrease in conductivity. The decrease in conductivity and the increase in activation energy caused by Sc3+ and Ga3+ doping were ascribed to the partial ordering of originally disordered oxygen vacancies and a decrease in the size of the triangle formed by two A-site cations and one B-site cation, through which the oxide ion proceeds, respectively.

Dye-sensitized solar cells (DSSCs) serve as low-costing alternatives to silicon solar cells because of their low material and fabrication costs. Usually, they utilize Pt as the counter electrode (CE) to catalyze the iodine redox couple and to complete the electric circuit. Given that Pt is a rare and expensive metal, various carbon materials have been intensively investigated because of their low costs, high surface areas, excellent electrochemical stabilities, reasonable electrochemical activities, and high corrosion resistances. In this feature article, we provide an overview of recent studies on the electrochemical properties and photovoltaic performances of carbon-based CEs (e.g., activated carbon, nanosized carbon, carbon black, graphene, graphite, carbon nanotubes, and composite carbon). We focus on scientific challenges associated with each material and highlight recent advances achieved in overcoming these obstacles. Finally, we discuss possible future directions for this field of research aimed at obtaining highly efficient DSSCs.

1998, a consensus meeting was held in Miyazaki, Japan, to develop an approach to management of febrile neutropenia (FN). The K-HOT study group decided to examine whether this proposal was applicable to clinical practice in a multicenter study. Patients who developed fever with neutrophil counts

CdS thin films of about 1 μm thickness were deposited from an aqueous solution containing Cd2+, Na2S2O3 and gelatin as the protective colloid to stabilize the size of colloidal sulfur at from 30 to 40 nm and keep the concentration to an appropriate value during electrolysis. The effects of concentrations of Cd2+ and S2O32− ions and the deposition potential on the composition of CdS films were studied. The reaction mechanism of CdS film formation on the electrode is discussed. CdS film, whose composition is uniform across the film and which does not contain excess metallic cadmium, can be deposited from a solution containing 0.50 to 2.00 mM Cd(NO3)2, 1.00 to 5.00 mM Na2S2O3 and 1.0 × 10−7 to 1.0 × 10−3 wt % gelatin.

Chronic lymphocytic leukemia (CLL) is a rare disease in Japan. Recent advances in molecular biology, diagnostic criteria and classification of CLL have reinforced the concept of each category of CLL as a distinct entity. Since there have been no recent studies on the incidence and prevalence of CLL in Japan, the Kyushu Hematology Organization for Treatment (K-HOT) Study Group conducted two studies of CLL. One study is a prospective registration of newly diagnosed hematological disorders, which gave us some idea of the incidence of CLL in our region (Kyushu island) where adult T-cell leukemia is endemic. A total of 677 patients with hematological disorders were registered over a 6-month period and 11 patients were diagnosed as having CLL among 182 leukemia patients. This amounts to 6% of all leukemias, which is twice as frequent as previously reported in Japan. The other study is a retrospective analysis of CLL. Eleven institutions of the K-HOT Group analysed their diagnostic records of chronic lymphoid leukemia, and 145 patients with CLL were found over a period of 3-12 yr. After the data were reviewed 11 patients were excluded through having a different type of leukemia. The proportion of chronic B-cell lymphoid leukemia was 73% (98/134), while that of T-cell leukemia was 18% (24/134). The proportion of T-cell chronic leukemia was 5-6 times higher than that in Western countries. Two institutions had a complete database on hematological disorders. From this database, the annual incidence of CLL was estimated to be 0.48 per 100 000. Thus, the incidence of CLL in Japan is at least 4-5 times lower than that in Western countries, suggesting that chronic B-cell leukemia is really rare, but chronic leukemia of T-cell lineage develops in Japan as frequently as in Western societies. Further investigation is required to delineate why the incidence of B-CLL is so low in Japan.

To improve the antitumor effect of chemotherapy on a target organ, we experimentally investigated pharmacokinetic alteration of methotrexate (MTX) induced by an electric current in rats to ascertain whether the local concentration of MTX could be enhanced while reducing the concentration in blood. Six male Wistar rats had platinum electrodes introduced into both kidneys. Three rats were subjected to direct current (3.5 V, 50 microA) for 3 hours, while another three control rats received no current. While providing the current to the treated group, all of the rats were intravenously injected with MTX at a dose of 1 mg/kg. The MTX concentration in urine (excreted from each ureter) and serum was measured by fluorescence polarization immunoassay. Cumulative MTX renal excretion rate was significantly higher in the cathode than anode side in the treated group (p < 0.01). Serum MTX concentration at 0 to 5 min was significantly reduced in the treated group (p < 0.03). The first part of the area under the curve (i.e., alpha curve) was markedly increased in the treated group versus controls (p = 0.05). Electric therapy using a slight direct current could gather anionized MTX to the cathode, while reducing MTX concentration in the serum of experimental rats.

Solid polymer electrolytes have been prepared consisting of magnesium or zinc trifluoromethanesulfonates [Mg(CF 3 SO 3 ) 2 or Zn(CF 3 SO 3 ) 2 ], ethylene carbonate, and propylene carbonate included in a photo-crosslinked polymer of poly-(ethylene glycol) diacrylate and reinforced by a porous polypropylene membrane. Their conductivities are 1.7×10 −4 S cm −1 at 1 mol% for Mg(CF 3 SO 3 ) 2 , 2.1×10 −4 S cm −1 at 4 mol% for Zn(CF 3 SO 3 ) 2 , and 4.3×10 −4 S cm −1 at 12 mol% for LiCF 3 SO 3 systems at 25°C. Their Arrhenius plots are almost linear between −5 and 55°C with 15–25 kJ mol −1 activation energy for conduction.

Hydrophilic carbon nano-particles have been prepared from a synthesized graphite block using electro-oxidation method in pure water. They are sub-micro meter in diameter depending on the electrolysis condition. They are used as the activator of lead-acid batteries and solid lubricants in non-oily lubricants as already reported at PRiME2012. In this presentation, we will introduce the application to the counter electrodes (CEs) of dye-sensitized solar cells (DSSCs) instead of Pt. We will report the preparation method, the results in characterization, and applications of hydrophilic carbon nano-particles especially on CEs in DSSCs. The weight % of solid carbonous material is 0.4 by the conventional electrolysis method around 10 V DC for 45 days. Increasing in the ratio of the graphite to the cell volume, the electrolysis time decreased and the weight % becomes 0.6 within 3 weeks. By XRD analysis, the dried powder of the produced material consists of mellitic acid (benzenehexacarboxylic acid) and graphite. CE was prepared by doctor blading a mixture of hydrophilic carbon (HC) nano-particles with TiO2 colloids on a FTO glass substrate. Thereafter, HC-CE was characterized using X-ray diffraction, profilometry, four-point probe testing, and CV. A 2 𝜇m thick HC-CE revealed a comparable catalytic activity to that of the Pt electrode under the same experimental conditions. A DSSC based on HC-CE was analyzed and showed 𝐽sc of 6.87 mA/cm2 close to that of DSSC with Pt-CE (7.0 mA/cm2). More importantly, DSSC based on HC-CE yielded a power-conversion efficiency (𝜂) of 2.93% under AM 1.5 irradiation (100 mW/cm2), which was comparable to that of DSSC based on conventional Pt-CE.Hydrophilic carbon nano-particles have been prepared from a synthesized graphite block using electro-oxidation method in pure water. They are sub-micro meter in diameter depending on the electrolysis condition. They are used as the activator of lead-acid batteries and solid lubricants in non-oily lubricants as already reported at PRiME2012. In this presentation, we will introduce the application to the counter electrodes (CEs) of dye-sensitized solar cells (DSSCs) instead of Pt. We will report the preparation method, the results in characterization, and applications of hydrophilic carbon nano-particles especially on CEs in DSSCs. The weight % of solid carbonous material is 0.4 by the conventional electrolysis method around 10 V DC for 45 days. Increasing in the ratio of the graphite to the cell volume, the electrolysis time decreased and the weight % becomes 0.6 within 3 weeks. By XRD analysis, the dried powder of the produced material consists of mellitic acid (benzenehexacarboxylic acid) and graphite. CE was prepared by doctor blading a hydrophilic carbon (HC) nano-particle on a FTO glass substrate. Thereafter, HC-CE was characterized using X-ray diffraction, profilometry, four-point probe testing, and CV. A 2 𝜇m thick HC-CE revealed a comparable catalytic activity to that of the Pt electrode under the same experimental conditions. A DSSC based on HC-CE was analyzed and showed 𝐽sc of 6.87 mA/cm2 close to that of DSSC with Pt-CE (7.0 mA/cm2). More importantly, DSSC based on HC-CE yielded a power-conversion efficiency (𝜂) of 2.93% under AM 1.5 irradiation (100 mW/cm2), which was comparable to that of DSSC based on conventional Pt-CE.

The difference in the electrical conduction behavior of various kinds of MnZr2n(PO4)3n (Mn=alkali metals, alkaline earth metals, Ag, Mn, Co, Ni, Zn, Cd, Pb, Al, Ga, and In) compounds (abbreviated as MZP) has been investigated by using frequency dispersion analysis. The conductivity of MZP with a NASICON-type structure mainly depended on the hopping rate of mobile cation; the conductivity of MZP with a sFe2(SO2)3-type structure was more affected by the mobile ion concentration than that with the NASICON-type one. These conclusions agree well with those obtained from crystallographic investigation.

Effects of the surface treatments of p-GaP electrodes with various etchants on the photoelectroreduction of CO2 were investigated in 0.1 mol dm−3 KHCO3 aqueous solution. The catalytic activities for CO2 photoelectroreduction of p-GaP electrodes depended on the etchants and also their crystallographic orientations, (100) or (111) faces. The reduction products were only HCOO− and CO from CO2, and H2 as a by-product. Aqua regia was prefer to produce HCOO− on both faces. Conc. HCl was effective for HCOO− formation on the (111) face. Although the alkaline potassium hexacyanoferrate(III) solution was effective for reducing the overpotential and increase the photocurrent, the main product was H2. Conc. HNO3 was not effective.

A needle-type glucose sensor has been developed using a new type of oxygen (O 2 ) electrode system composed of a 0.5 or 1.0 mm Ti wire about 2.5 mm in diameter and 35 mm long, whose top is anodically oxidized. It responds well to O 2 tension in a saline solution. As the residual current of the prototype sensor is rather large at zero O 2 tension, the oxidized surface has been modified with Pt by electroplating. Thus the O 2 reduction preferentially proceeds on the Pt sites, and the applied potential for the sensor becomes less negative than for the prototype. Miniaturization of the sensor has been performed by using the side wall of the 0.3 mm Ti wire ≈ 1.1 mm in diameter and 15 mm long as the sensing and enzyme immobilizing site. GOD is immobilized on the Pt-modified surface of the Ti electrode with a silanizer using glutaraldehyde and BSA, or with an electropolymerized polypyrrole film. Both sensors linearly respond to glucose over a range of more than 500 mg/dl. The shape of the miniature sensor is promising for immobilizing the enzyme and coating the membranes easily.

Cu-doped p-type CdTe thin films have been electrodeposited at -0.35 V vs. Ag/AgCl from a sulfuric acid solution of pH I containing 0.1 M CdSO 4 , I mM TeO 2 , and various concentrations of CuSO 4 . Deposited films were annealed at 350°C under N 2 flow. The films were characterized with X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, and a reflectance meter. The resistivity and the carrier concentration of the films were measured using the van der Pauw method and Hall effect measurement. This is the first study to investigate the effect of the CuSO 4 concentration on the composition, the crystallinity, and the electric properties of Cu-doped CdTe films prepared by electrodeposition The conductivity of the CdTe films linearly increases by 0.14-104.5 S/cm, and the hole concentration [log(h/cm 3 )] increases from 17.3 to 20.0 as the CuSO 4 concentration rises from I × 10 -7 to 10 -5 M.

The crystal structure, phase transition, electrical conduction behavior of various kinds of MIIZr4(PO4)6 (MIIZP) compounds (MII = Mg, Ca, Sr, Ba, Mn, Co, Ni, Zn, Cd, and Pb) have been investigated. The Mg, Co, Ni, and Zn compounds are of the β-Fe2(SO4)3-type structure and show an order-disorder transition between 600 and 720 °C; the Ca, Sr, Ba, Cd, and Pb compounds, however, are of the NASICON-type structure and do not show any phase transition between r.t. and 1000 °C. The Mn compound sintered at 900 °C shows the former characteristics (the phase transition temperature is around 560 °C), and that sintered above 900 °C the latter. The ZnZP and MnZP show the highest conductivity, ca. 2 × 10−3 and ca. 8 × 10−4 S cm−1 at 800 °C, in the β-Fe2(SO4)3- and the NASICON-type structure, respectively. The ionic size of the mobile cation is the predominant factor regarding ionic conduction in the zirconium phosphate framework.

An enhancement of electric conductivity was observed by substitution of Si4+ for P5+ in LiZr2(PO4)3, MgZr4(PO4)6, and ZnZr4(PO4)6 solid electrolytes with a β-Fe2(SO4)3-type structure. An increase in the concentration of interstitial Li+ ion resulted in the conductivity enhancement for the Li compound, whereas an increase in the compactness of sintered specimen for the Mg and Zn compounds.

Gas diffusion electrodes (GDEs) promising to use electrochemical reaction of gases at higher rates such as in fuel cells were used for CO2 electro‐reduction. Cu powder, Cu and ZnO mixed powder, and CuO/ZnO mixed oxides were examined as the catalysts. The reduction products with Cu‐GDEs in K2SO4 aq. soln. were CH4, C2H4, C2H5OH, CO, HCOO−, etc. The purer and the smaller particle size of the Cu powder, it shows the higher activity and efficiency for CO and hydrocarbons formation. CO2 reduction can be carried out ca. 100 times greater rate using a GDE than that with a Cu‐foil electrode. With GDEs of CuO/ZnO = 3/7, the main product was C2H5OH with an efficiency of 17% with selectivity of 88% at −1.32 V. With GDEs of Cu/ZnO = 3/7 reduced by H2, the selectivity became poorer due to additional production of n‐C3H7OH and C2H4, although the total efficiencies for CO2 reduction became 41% at −1.30 V.

Aqueous salt solutions of ionic surfactants in both spherical and rod-like micelles have been treated on the basis of a statistical thermodynamic theory, and the double logarithmic relationship between micelle molecular weight and ionic strength is derived for each micelle. Counterion binding on both micelles are assumed to occur specifically, and their degrees of dissociation are related to the slopes of the linear double logarithmic relations. It is found from the relationship observed for typical surfactants that the effective charge of spherical micelles is 29±4. The degree of dissociation of rod-like micelles of these surfactants is primarily determined by the counterion species, yielding values 0.8 for Na+, 0.4–0.6 for Cl− and 0.2–0.3 for Br−. Hydrophilic hydration of both micelles can be evaluated from the intercepts of the linear relations. Hydrophilic hydration acts repulsively in spherical micelles, while it is attractive or much less repulsive in rod-like micelles.

The influence of the light intensity on the photoelectroreduction of CO2 was investigated at a p-GaP photocathode in 0.1 mol dm−3 KHCO3 aqueous solution. The faradaic efficiencies for the formation of HCOO− and H2 were strongly affected by the light intensity. The maximum faradaic efficiency for HCOO− production was close on 70%. A mechanism of variation of the efficiencies with light intensity was discussed.

Zinc ion conducting materials have been found in the system Zn-Zr-PO4, and the composition of the material with the maximum conductivity has been estimated to be ZnZr4(PO4)6 having the similar crystal structure as that of MgZr4(PO4)6. The conductivities of this compound are 1.34×10−6 and 1.57×10−3 S/cm at 500 and 900°C, respectively, and the activation energies for conduction are 90 kJ/mol between 750 and 900°C and 134 kJ/mol between 500 and 700°C, respectively. The charge carrier of this material was confirmed to be zinc ions by the Tubandt's method and the electron probe micro-analysis.

The spinnability was measured for aqueous viscoelastic solutions of tetradecyl- and hexadecyltrimethylammonium salicylates (C14TASal, C16TASal) in the absence and presence of sodium salicylate (NaSal) and sodium bromide (NaBr). The spinnability is classified into two types, D and C. While the intrinsic drawing length in type D is proportional to the drawing velocity, the drawing intrinsic length in type C decreases with the drawing velocity or is independent of it. The spinnability changes from type D to C, as the drawing velocity and the surfactant concentration increase, and the temperature lowers. The effect of salt is different between NaSal and NaBr. It can be assumed that a pseudo-network structure composed of rod-like micelles is formed in viscoelastic and spinnable surfactant solutions. Then, the spinnability depends on the balance between the elasticity and the viscosity in which the structure results.