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Articles 2221 - 2250 of 2635

Full-Text Articles in Chemistry

The Effect Of Preparation Condition On The Photoelectrochemical Performance Of Both The Pani Film And Tio2-Pani Composite Film On Au, Huai-Guo Huang, Hong-Ping Zhang, Zhi-Xin Zheng, Yan-Yan Xi, Ling-Ling Wu, Zhong-Hua Lin May 2001

The Effect Of Preparation Condition On The Photoelectrochemical Performance Of Both The Pani Film And Tio2-Pani Composite Film On Au, Huai-Guo Huang, Hong-Ping Zhang, Zhi-Xin Zheng, Yan-Yan Xi, Ling-Ling Wu, Zhong-Hua Lin

Journal of Electrochemistry

Both the PANI (polyaniline) film and TiO2-PANI composite film on the PATP(paminothiophenol)/Au substrate were obtained under different preparation condition by electrochemical methods, and their photoelectrochemical performances were alo studied. The resultsshowed that the photoelectrochemical performances of the films depend deeply on the comditionsof preparation. The self-assembling of PATP favors the adhesion of PANl. The partially-oxidizedPANI has a greater photoelectrochemical response than that of the reduced PANI and oxidized PANl. There is an optimum of film thickness for the photoelectrochemical performance of PANI film. Heat treating is in favor of the photoelectrochemical performance of TiO2, but decreases …

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Study On Corrosion Resistance Of Electroless Nickel Composite Coatings, Tsong-Jen Yang, Meng-Feng Jou May 2001

Study On Corrosion Resistance Of Electroless Nickel Composite Coatings, Tsong-Jen Yang, Meng-Feng Jou

Journal of Electrochemistry

The eletroless nickel composite coating was prepared by uniform dispersion of diamond (or PTFE) particles throughout electroless nickel deposition. Corrosion resistance of composite coating in 3.5% NaCl aqueous solution was investigated by electrochemical analysis, dipping test and salt spray test. The results showed that the corrosion resistance of composite coating was inferior to that of electroless nickel coating if small amount of particles was added to the composite coating. Microsturctural analysis by SEM, AES, XRD, and EPMA indicated that the distribution of phosphorus is not homogeneous in the composite coating. The phosphorus_rich region acts as microcathode, however, the phosphorus-lean region …

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Preparation Of Ti-Based Nanocrystalline Tio2 Film Electrode With High Activity, Dao-Bao Chu, Guang-Xia Shen, Xing-Fu Zhou, Chang-Jian Lin, Hua-Shui Lin May 2001

Preparation Of Ti-Based Nanocrystalline Tio2 Film Electrode With High Activity, Dao-Bao Chu, Guang-Xia Shen, Xing-Fu Zhou, Chang-Jian Lin, Hua-Shui Lin

Journal of Electrochemistry

The potentiostatic electrosynthesis of Ti(EtO)4 was studied by anodic dissolution of metal titanium(TA1) in solution of 0.005 mol·L-1 (EtO)4NBr in the ethanol (AR) in the presence negligible CH3COCH2COCH3. The Ti-based nanocrystalline TiO2 Film electrode (Ti/nano-TiO2) was prepared by sol-gel method. By TEM, SEM and XRD, it has been shown that the anatase particle of TiO2 was 10～35 nm in diameter and the film was 0.5 μm in thickness. The nanocrystalline film was composed of a three-diminsional network of interconnected particles. Reodx behavior and electrocatalytic activities of …

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New Progress In Studies Of Lithium Nickel Oxide As Positive Electrode Materials Of Lithium Ion Batteris, Han-San Liu, Yong Yang, Zhong-Ru Zhang, Zu-Geng Lin May 2001

New Progress In Studies Of Lithium Nickel Oxide As Positive Electrode Materials Of Lithium Ion Batteris, Han-San Liu, Yong Yang, Zhong-Ru Zhang, Zu-Geng Lin

Journal of Electrochemistry

Lithium nickel oxide as the positive electrode of lithium ion batteries has aroused more and more interests.This paper reviews the recent reserches on synthesis and element-substitution of LiNiO2 cathode material,and summarizes the intrinsical relationship between properties and sturcture of the material.The developments of new synthesis methods and mutilsubstitution of the material are expecting to be studied in the future research.

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Electrochemistry Characteristic Of Carbon Steel Under Biofilm And Sulfide Film, Ze-Hua Dong, Xing-Peng Guo, Jia-Shen Zheng, Li-Ming Xu May 2001

Electrochemistry Characteristic Of Carbon Steel Under Biofilm And Sulfide Film, Ze-Hua Dong, Xing-Peng Guo, Jia-Shen Zheng, Li-Ming Xu

Journal of Electrochemistry

Wire Beam Electrode (WBE) made of Q235 carbon steel was applied to study theheterogeneous corrosion beneath biofilm formed by Sulfate Reducing Bacteria (SRB) in cultureand sulfide film in solution with 1% NaCl and 300 mg/L⋅S2-. The potential, galvanic density mapping, as well as polarization curve and Electrochemical Impedance Spectrum (EIS) were measured to predict the localized corrosion under biofilm and sulfide film. As a result, the mappingshowed the potential fluctuation on the WBE suface decreased over time due to the conductivityof the biofilm and sulfide film. Therefore, the potential mapping could not be a criterion of localized corrosion …

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The Applications Of Confocal Raman Micro-Spectroscopy For Study Of Practical Electrode Materials, Yong Yang, Wei Chu, Jun-Min Nan, Xun-Guang Chen, Zu-Geng Lin Feb 2001

The Applications Of Confocal Raman Micro-Spectroscopy For Study Of Practical Electrode Materials, Yong Yang, Wei Chu, Jun-Min Nan, Xun-Guang Chen, Zu-Geng Lin

Journal of Electrochemistry

Some recent research work about applications of confocal Raman micro spectroscopy for study of practical electrode materials carried out in our lab has been briefly introduced. The examples include study of electrochemical Li+ intercalation process, characterization of surface oxide film on AB5 type electrodes and passive film and pitting corrosion of Rebar electrodes.

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A Study On The Performance Of Matrix Prepared By Tape Cast And Its Molten Carbonate Fuel Cells (Mcfcs), Hua-Xin Lin, Bao-Lian Yi, Li Zhou, Chang-Qing He, Lian-Ying Kong, En-Jun Zhang Feb 2001

A Study On The Performance Of Matrix Prepared By Tape Cast And Its Molten Carbonate Fuel Cells (Mcfcs), Hua-Xin Lin, Bao-Lian Yi, Li Zhou, Chang-Qing He, Lian-Ying Kong, En-Jun Zhang

Journal of Electrochemistry

The matrix prepared with γ-LiAlO2 powder and by tape cast displayed higher ability of preventing from gas cross over and lower ohmic polarization. The voltages of the stack (three cells, 122 cm2) stacked with the matrix were 2.02 and 1.78 V at 200 and 246 mA/cm2, respectively, and the output power reached 53.4 W. The cell (28 cm 2) voltages were 0.85 and 0.75 V at 200 and 300 mA/cm2, respectively, and the output power was about 6.6 W. Compensating the shrinkage of matrix in stacking cells promoted the enhancement of the …

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Two-Dimensional Surface Raman Imaging Of A Roughened Iron Electrode In Saline Water, Pei-Gen Cao, Jian-Lin Yao, Jun-Wei Zheng, Bin Ren, Ren-Ao Gu, Zhong-Qun Tian Feb 2001

Two-Dimensional Surface Raman Imaging Of A Roughened Iron Electrode In Saline Water, Pei-Gen Cao, Jian-Lin Yao, Jun-Wei Zheng, Bin Ren, Ren-Ao Gu, Zhong-Qun Tian

Journal of Electrochemistry

The analysis of the composite and distribution of iron oxide due to pit corrosion in saline solutions (3.4% NaCl) is of great importance. Many electrochemical methods, XPS, and other photoelectronic techniques have been applied to this domain. Surface enhanced Raman scattering (SERS) spectroscopy can provide the vibrational information of surface species with high sensitivity and is very useful in the study of surface chemistry of iron. Notwithstanding, the application of SERS in iron corrosion is hampered for its SERS-inactivity. Efforts have been devoted to extend the use of SERS to the study of iron.

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How Can Direct Mthanol Fuel Cell Benefit From Carbonate Media, Lin Zhuang, Yang Wang, Jun-Tao Lu Feb 2001

How Can Direct Mthanol Fuel Cell Benefit From Carbonate Media, Lin Zhuang, Yang Wang, Jun-Tao Lu

Journal of Electrochemistry

The kinetics of methanol oxidation and oxygen reduction in 0.5 mol/L K2CO3 were compared with those in 0.5 mol/L H2SO 4. Experiments revealed that carbonate media could be more beneficial to direct methanol fuel cell(DMFC). Firstly, both electrode reactions show better performance in the carbonate than in the acid; secondly, materials other than noble metals become possible to be used as the anodic and cathodic catalysts; thirdly, the potential dectease caused by methanol crossover could be depressed by using metal oxide catalysts not stable in acid, such as MnO2.

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Synthesis Of Limn2O4-ΔClΔ Cathode Material By Like-Sol-Gel Methode, Zhao-Yong Chen, Yi He, Xing-Quan Liu, Zhi-Jie Li, Zuo-Long Yu Feb 2001

Synthesis Of Limn2O4-ΔClΔ Cathode Material By Like-Sol-Gel Methode, Zhao-Yong Chen, Yi He, Xing-Quan Liu, Zhi-Jie Li, Zuo-Long Yu

Journal of Electrochemistry

LiMn2O4-δClδ was synthesized by like sol gel methode, with calculated LiOH·H2O, Mn(No3)2⋅6H2O and LiCl·H2O, and made electrochemical test with these compounds as positive materials. Result demostrated that LiMn2O4-δClδ cathode material has exellent stability and nearly no capacity loss after reaching stability.

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In Situ Raman Spectroelectrochemical Characterization Of The Prussian Blue/Platinum Modified Electrode, Xiao-Wei Cao, Rong Wang, Gui-Hua Wang, Zong-Rang Zhang Feb 2001

In Situ Raman Spectroelectrochemical Characterization Of The Prussian Blue/Platinum Modified Electrode, Xiao-Wei Cao, Rong Wang, Gui-Hua Wang, Zong-Rang Zhang

Journal of Electrochemistry

Prussian Blue is known to be deposited electrochemically on the electrode surface, producing a dense redox active layer. Since the Prussian Blue modified electrode was first reported by Neff in 1978, different in situ spectroelectrochemical techniques have been widely used to investigate its electrochemical mechanism. But no research work related to the in situ Raman spectroscopic studies on it has been reported. In this paper we try to characterize the nature of thin Prussian Blue films on platinum substrates with in situ Raman spectroelectrochemical technique.

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Adsorption Behavior Of Co At The Ultrathin Rh And Pt Film Electrodes, Yong Xie, Xiao-Qin Li, Bin Ren, Zhong-Qun Tian Feb 2001

Adsorption Behavior Of Co At The Ultrathin Rh And Pt Film Electrodes, Yong Xie, Xiao-Qin Li, Bin Ren, Zhong-Qun Tian

Journal of Electrochemistry

Pt group metals have been widely used in catalysis such as hydrogenation of organic compounds and the oxidation of carbon monoxide. The information about CO adsorption on the Pt group surfaces and the influence of other surface species, such as hydrogen and CO2 will be greatly helpful to elucidate the adsorption behavior of CO on Pt group metal surfaces and get a deeper understanding of catalytic mechanisms of Pt group metals. Surface enhanced Raman spectroscopy (SERS) has been becoming an increasingly important means to characterize the electrochemical metal solution interface over the past two decades. Our laboratory has successfully …

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Adsorption And Oxidation Of Ethanol On Nm-Pt/Gc Electrode Ii. Eqcm And In-Situ Ftir Spectroscopic Studies In Acid Media, Guo-Liang Chen, Sheng-Pei Chen, Zhi-You Zhou, Chun-Hua Zhen, Shi-Gang Sun Feb 2001

Adsorption And Oxidation Of Ethanol On Nm-Pt/Gc Electrode Ii. Eqcm And In-Situ Ftir Spectroscopic Studies In Acid Media, Guo-Liang Chen, Sheng-Pei Chen, Zhi-You Zhou, Chun-Hua Zhen, Shi-Gang Sun

Journal of Electrochemistry

The adsorption and oxidation of ethanol on nm Pt/GC electrode in acid solutions containing 0.1 mol·L -1 H2SO4 +0.1 mol·L -1 CH3CH2OH was investigated by using cyclic voltammetry, EQCM and in situ FTIR spectroscopy. The experimental results demonstrated that the oxidation of CH3CH2OH is closely relaed to solution acidity and oxygen species on electrode surface; CH3CH2OH was oxidized on nm Pt/GC electrode in acidic media via a dual path reaction mechanism, i.e . CH3CH2OH may be oxidized into CO2 through …

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The Photoelectrochemistry Of Tio2-Polyaniline Composite Film, Huai-Guo Huang, Zhi-Xin Zheng, Jin Luo, Hong-Ping Zhang, Ling-Ling Wu, Zhong-Hua Lin Feb 2001

The Photoelectrochemistry Of Tio2-Polyaniline Composite Film, Huai-Guo Huang, Zhi-Xin Zheng, Jin Luo, Hong-Ping Zhang, Ling-Ling Wu, Zhong-Hua Lin

Journal of Electrochemistry

A TiO2 and polyaniline (PANI) composite film was obtained by electrochemical methods. The SEM image of the composite film showed that the PANI film is almost completely covered with TiO2 efficiency. The spectra of photocurrent for the TiO2-PANI composite film were different from these of TiO2 film photosensitized by PANI. The bandgap energy of TiO2 film on partially oxidized PANI film was determined as 3.0 eV by the threshold energy of photocurrent band for TiO2. The spectra of photocurrent for partially oxidized PANI film electrode suggested that it has the characteristics of …

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Catalytic Effect Of Cl- On Electrodeposition Of Binary Zinc Alloys With Iron Group Metals, Ren-He Yin, Zheng-Hua Fang, Wei-Min Cao, A.Za Karia, Rong-Ming Zhou Feb 2001

Catalytic Effect Of Cl- On Electrodeposition Of Binary Zinc Alloys With Iron Group Metals, Ren-He Yin, Zheng-Hua Fang, Wei-Min Cao, A.Za Karia, Rong-Ming Zhou

Journal of Electrochemistry

Zinc iron group metal alloys were deposited under coulostatic (10C⋅cm-2) at 40 ℃ chloride baths. The deposited alloys were quantitatively analyzed by Atomic Absorption Spectrometry. The current efficiency, percent content and partial polarization curves were obtained by the results. The morphology of the deposits was observed by means of Scanning Electron Microscopy(SEM). We observe that the electrodeposition of zinc iron group metal alloys is one of the best known examples of anomalous codeposition. We found the catalytic effect of Cl- on the electrodeposition behavior of iron group metal. Overpotential of iron group metal droped abruptly at high …

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The Effect Of Aluminium Oxide And Cerium Oxide As Dispersoids In Chitosan-Lithium Acetate Complexes, Hoi Mien Leow Jan 2001

The Effect Of Aluminium Oxide And Cerium Oxide As Dispersoids In Chitosan-Lithium Acetate Complexes, Hoi Mien Leow

Student Works (2000-2009)

In this study, chitosan with 85% deacetylation was used with Ni(OAc)₂·2H₂O as doping salt and Al₂O₃, or CeO₂ as dispersoid. They were mixed in certain weight percentages and dissolved in 100ml of 0.5% acetic acid solution. These solutions were poured into petri dishes and left at room temperature for film formation. Infrared Spectroscopy has shown that there is interaction between chitosan and LiOAc with and without dispersoid. The peaks are shifted. broadened. split and differs in intensity. The electrical conductivity of all samples was calculated using the bulk resistance value obtained from the complex admittance plot. The highest electrical conductivity …

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Preparation And Characterization Of Lithiated Cathode Materials For Lithium Batteries, Shanti Navaratnam Jan 2001

Preparation And Characterization Of Lithiated Cathode Materials For Lithium Batteries, Shanti Navaratnam

Student Works (2000-2009)

Four different cathode materials, LiNiO₂, LiCoO₂, LiCo₀.₂ Ni₀.₈O₂ and LiCo₀.₄, Ni₀.₆O₂ were synthesized by sol - gel technique. The prepared materials were characterized X-ray diffraction pattern, FT-IR and cyclic voltammetry. X-ray diffraction pattern shows crystallinity of materials, increases with higher calcination temperature. From FT- IR studies, it was shown, that the purity of sample also increased with prolong heating at higher temperatures. It was possible to obtain pure and highly crystalline LiNiO₂ after heating for fourteen hours at 800°c. Cyclic voltammetry shows the four prepared materials are suitable for fabrication of cathode, as lithium ions can intercalate and de-intercalate. LiNiO₂ …

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Infared Spectroscopy And Electrical Conductivity Of Copper(Ii) Cinnamate And Iodine-Doped Copper(Ii) Cinnamate, Kumar Krishnan Jan 2001

Infared Spectroscopy And Electrical Conductivity Of Copper(Ii) Cinnamate And Iodine-Doped Copper(Ii) Cinnamate, Kumar Krishnan

Student Works (2000-2009)

Copper(II) cinnamate (CC) was prepared from copper(II) acetate monohydrate and cinnamic acid. It was a light-blue powder. The Fourier Transform Infrared (FTIR) spectrum of CC, recorded as potasium bromide (K.Br) disc, indicated the presence of all bonds and functional groups expected of it and showed that it exist as an equal mixture of cis- and trans- isomers. The conductivity of CC at room temperature was 5.22 x 10⁻¹¹Scm⁻¹. It showed metallic behaviour in the temperature range 78-300 K, and its conduction mechanism obeyed Mott's variable range hopping (VRH) model in the same temperature range. The density of states at Fermi …

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Dynamics Of Polyacrylates In Concentrated Chloroform Solutions, Frank D. Blum, Raj B. Durairaj Jan 2001

Dynamics Of Polyacrylates In Concentrated Chloroform Solutions, Frank D. Blum, Raj B. Durairaj

Chemistry Faculty Research & Creative Works

The dynamics of polymers in polymer solutions have not been probed in great enough detail to provide a coherent picture of the behavior of these polymers, especially in more concentrated solutions. To help understand this behavior further, we have prepared a series of backbone-labeled polymers including poly(n-butyl acrylate)-d1 (PNBA). These provide a basis for comparison of the behavior among a group of related polymers. The dynamics have been probed by using deuterium relaxation times. Since the relaxation times are relatively fast and the quadrupolar relaxation mechanism is well understood, data from this technique provide a convenient means for comparison of …

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Glass Transition Behavior Of Pmma Thin Films, Moses T. Kabomo, Frank D. Blum Jan 2001

Glass Transition Behavior Of Pmma Thin Films, Moses T. Kabomo, Frank D. Blum

Chemistry Faculty Research & Creative Works

In the last decade there has been an increased interest in the study of the properties of supported thin polymer films. This has been prompted by the incorporation of thin films into device applications and many other technologies. Although not without controversy, a large body of experimental work indicates departures from bulk behavior by thin films. Strong evidence from both theoretical and experimental work shows that the interaction of polymer with a substrate alters the polymer conformation and mobility. A variety of techniques has been employed to probe the mobility of thin supported polymer films. Some of these techniques indirectly …

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Graduated Segmental Mobility In Polymer Layers On Silica, Frank D. Blum, Crystal E. Porter, Wuu-Yung Lin Jan 2001

Graduated Segmental Mobility In Polymer Layers On Silica, Frank D. Blum, Crystal E. Porter, Wuu-Yung Lin

Chemistry Faculty Research & Creative Works

The behavior of thin polymer layers on oxide substrates has gotten a great deal of attention as the size of materials, and hence polymer films, has gotten smaller. Indeed, the properties of adsorbed polymers are such that they can be different from those of bulk polymers, especially when the films are very thin. A wide variety of studies have been made on adsorbed polymers and sometimes the results seem contradictory. One of the properties often measured in thin films is the apparent glasstransition temperature, Tg. In principle, many techniques are sensitive to phenomenological changes occurring around Tg and, therefore, can …

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Thermal Analysis Of Ultrathin Ps-R-Pmma Copolymer Films On Silica, Bing Zhang, Frank D. Blum Jan 2001

Thermal Analysis Of Ultrathin Ps-R-Pmma Copolymer Films On Silica, Bing Zhang, Frank D. Blum

Chemistry Faculty Research & Creative Works

Composite materials represent a major part of man-made materials that are used in many applications. The interaction of polymers with surfaces plays a crucial role in the final properties of these materials and, by understanding the surface processes and adsorption mechanisms, better systems can be designed. Therefore, the behavior of polymer molecules at interfaces has been the topic of many studies in recent years and a rough picture has been obtained. Keddie et al. Obtained experimental results showing the dependence of the glass transition temperature (Tg) on the thickness of supported polystyrene films using ellipsometry. Later, they also investigated supported …

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Dynamics Of Poly(Vinyl Acetate)-D₃ On Silica, Robert D. O'Connor, Frank D. Blum, Gu Xu Jan 2001

Dynamics Of Poly(Vinyl Acetate)-D₃ On Silica, Robert D. O'Connor, Frank D. Blum, Gu Xu

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Poly(vinyl acetate) (PVAc) is an important polymer in applications because of both its bulk and surface characteristics. Its chain architecture gives it a low Tg and, generally, good qualities for processing and applications, which include paints, adhesives, thin films and surface coatings. In this study, we investigate the surface dynamics of PVAc absorbed onto silica with deuterium nuclear magnetic resonance (2H NMR). For dynamics studies, 2H NMR is an excellent technique because it uses an innocuous probe that can report on correlation times (τc) from approximately 10-8 s to 10 s. We report the use of two-dimensional exchange NMR (2D-X) …

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Evidence Of Nanostructure In Multilayer Cdse Thin Films, Suganthi Devadason Jan 2001

Evidence Of Nanostructure In Multilayer Cdse Thin Films, Suganthi Devadason

Student Works (2000-2009)

Cadmium Selenide multilayer thin films have been prepared using physical vapour deposition method. Alternate layers of Cadmium and Selenium are deposited on unheated glass substrates. Morphological study of the samples has been done using SEM micrographs with a magnification of 5000. The EDX analysis gives the quantitative atomic percentage content of elements present in the samples. It is found that the high Cadmium content in the samples increased the crystallinity. From XRD measurements, it is evident that many films are polycrystalline in nature with a peak corresponding to < 111 > plane orientation of the zinc blende structure. The lattice constant of the …

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Sulphide Based Materials As Potential Anodes In Lithium Ion Cells, Azlin Sanusi Jan 2001

Sulphide Based Materials As Potential Anodes In Lithium Ion Cells, Azlin Sanusi

Student Works (2000-2009)

Sulphides based compounds PbS and SnS have been studied as possible anode material in lithium ion cell. PbS was prepared by the chemical bath deposition technique and SnS by the double decomposition method. Both samples were characterized by the powder X-ray diffraction technique and energy dispersive analysis of X-rays (EDAX). The room temperature electrical conductivity of PbS is 2.6 x 10⁻⁴ S cm⁻¹ and SnS is 5.3 x 10⁻⁷ S cm⁻¹ while at 90°C the electrical conductivity of PbS is 3.3 x 10⁻⁴ S cm⁻¹ and SnS is 2.90 x 10⁻⁶ S cm⁻¹ Cyclic voltammetry determined the potential anode ability …

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Synthesis And Characterization Of Lithiated Mixed Metal Oxides For Lithium Ion Rechargeable Batteries, Seng Gee Tan Jan 2001

Synthesis And Characterization Of Lithiated Mixed Metal Oxides For Lithium Ion Rechargeable Batteries, Seng Gee Tan

Student Works (2000-2009)

Lilhiated mixed metal oxides for lithium ion rechargeable batteries were prepared by the sol gel technique. Samples consisting of lithium acetate, nickel nitrate, cobalt nitrate, manganese acetate and aluminium fluoride were characterised using X-ray Diffraction (XRD), Differential Scanning Calorimetry (DSC), Fourier Transform Infrared Spectroscopy (FTIRS). Energy Dispersive Analysis of X-rays (EDAX) w1d Cyclic Voltammetry (CV). Thermal characterization shows that the acetates, nitrates and fluorides of precursors material deform at temperature between 50° to 100°C and the products begin to form at a temperature between 264°C to 271°C. FTIR studies show that the materials must be heated for a longer time …

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Effect Of Electron-Attracting Groups On The Thermal Stability Of Subtituted Copper (Ii) Benzoate, Fauziah Kamaruddin Jan 2001

Effect Of Electron-Attracting Groups On The Thermal Stability Of Subtituted Copper (Ii) Benzoate, Fauziah Kamaruddin

Student Works (2000-2009)

Copper(II) benzoate, copper(II) 4-fluorobenzoate, copper(II) 4-chlorobenzoate, copper(II) 4-bromobenzoate, copper(II) 4-iodobenzoate, copper(II) pentafluoro benzoate, copper(II) 4-nitrobenzoate and copper(II) 3,5-dinitrobenzoate are potential low dimensional thermally stable molecular electronics. The them1al properties of these samples are investigated by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). TGA reveals that copper(II) benzoate (CB) slowly decomposed at 243.5°C, losing 67.7% of its weight at 515°C. The DSC shows two endotherms separated by an exotherm. The first endotherm at 224°C may due to the breaking of bridging bond to give benzoyloxy radicals. The exotherm at 231°C may due to the formation of volatiles from the decomposition …

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Characterization Of Lithium Intercalation Oxides Based On Manganese And Copper, Vengidason Seguprakash Jan 2001

Characterization Of Lithium Intercalation Oxides Based On Manganese And Copper, Vengidason Seguprakash

Student Works (2000-2009)

In this study, several lithium intercalation compounds have been synthesized and characterized. Lithium manganese copper oxide cathode materials were prepared by sol gel method using tartaric acid as the gelating agent. Five types of cathode materials were synthesized. The sol gel technique has permitted the synthesis of manganese oxides that are capable of reversibly intercalating large amounts of lithium ions. To see the effect of adding copper to lithium manganese oxide several experiments were carried out. These include X-Ray diffraction to see whether the LiMn₂O₄ lattice has widened or collapsed. It was seen that LiMn₂O₄ and LiCu₂O₂ XRD patterns were …

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The Development Of Carbon Monoxide Tolerant Catalysts For Proton-Exchange Membrane Fuel Cell, Zhong-Jun Hou, Hong-Mei Yu, Bao-Lian Yi, Ming Han Nov 2000

The Development Of Carbon Monoxide Tolerant Catalysts For Proton-Exchange Membrane Fuel Cell, Zhong-Jun Hou, Hong-Mei Yu, Bao-Lian Yi, Ming Han

Journal of Electrochemistry

High over-potential of proton exchange membrane fuel cell (PEMFC) anode caused by carbon monnoxide poisoning when reformate or methanol is used as fuel is main obstacle to the high performance of PEMFCs. Using carbon monoxide tolerant catalysts is the most hopeful way to solve the CO problem. The CO poisoning problem is reviewed briefly in this paper, and the development of CO tolerant catalysts is introduced in details, including electrocatalysts activity, preparation method and mechanism of tolerance to CO.Mo and W can improve catalysts' CO tolerance. Multi-component catalysts are expected to be more tolerant to CO.

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A Study Of The Adsorption Behaviors On The Surface Of Gold Electrode By In-Situ Electrochemical Raman Spectroscopy, Xia-Qin Wu, Xiao-Wei Cao, Zhe-Su Wang, Xiao-Yun Meng, Zong-Rang Zhang Nov 2000

A Study Of The Adsorption Behaviors On The Surface Of Gold Electrode By In-Situ Electrochemical Raman Spectroscopy, Xia-Qin Wu, Xiao-Wei Cao, Zhe-Su Wang, Xiao-Yun Meng, Zong-Rang Zhang

Journal of Electrochemistry

The results of in-situ measurements with Raman spectroelectrochemical thchnique on bare gold electrode and adenine modified gold electrode were reported. The adsorption behaviors of adenine and superoxide dismutase (SOD) and their interactions with gold electrode were analyed. The mechanism of promoted electron transfer process of SOD in the presence of adenine at gold electrode surface is discussed.

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