bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis and Study the Chelating Activity of some Polymers Containing Heterocyclic Rings, The Derivatives from 1,2,4- trizol Levofloxacin acid
Authors: Saddam Fandi Al-Mathkuri Tahseen , Mohammed Saleh Al-Jubori Hamid , Taha Saleh Ali
Published: August 2018

The compound 6-amino-5-mercapto-4H-1,2,4-triazol-3-yl)-9-fluoro-3-methyl-10-(4-methylpiperazin-1-yl)-2,3-dihydro-7H-[1,4] oxazino[2,3,4-ij] quinolin-7-one (M1) synthesize from the reaction of thiocarbohydrazide with levofloxacin acid by using ethanol as a solvent, phenolic Schiff bases (Z)-9-fluoro-6-(4-((4-hydroxybenzylidene) amino)-5-mercapto4H1,2,4-triazol-3-yl)-3-methyl-10-(4-methylpiperazin-1-yl)-2,3-dihydro-7H-[1,4]oxazino[2,3,4-ij] quinolin-7-one (M2), (Z)-6-(4-((2,4-dihydroxybenzylidene) amino)-5-mercapto-4H-1,2,4-triazol-3-yl)-9-fluoro-3-methyl-10-(4-methylpiperazin-1-yl)-2,3-dihydro-7H-[1,4] oxazino[2,3,4-ij]quinolin-7-one (M3) and (Z)-6-(4-((5-chloro-2-hydroxybenzylidene) amino)-5-mercapto-4H-1,2,4-triazol-3-yl)-9-fluoro-3-methyl-10-(4-methylpiperazin-1-yl)-2,3-dihydro-7H- [1,4] oxazino[2,3,4-ij] quinolin-7-one (M4) were prepared from the reaction of trizol derivative of [M1] compound with the appropriate phenolic aldehydes by using ethanol as a solvent. The synthetic Schiff bases used to prepare numbers of phenolic polymers [M5-M7] from the reaction of Schiff bases [M2-M4] with phenol formaldehyde. The analytical efficiency of the synthetic chelating polymers studied by the batch method with different transition metals ions (Cd2+, Fe3+, Cu2+), in terms of the effect of treatment time and the pH on the loading capacity of the polymers, controlling the other factors such as temperature, ions concentration and quantity of polymers. The result shows that the capacity of the polymer increased with increasing of the pH and treating time. The synthetic compounds were characterized by various instrumental techniques like FTIR, 1H-NMR, DTG and TGA studies.These spectral and thermal studies provide very valuable information about the structural features.
Electrochemical Trifluoromethylation of Isonicotinic acid hydrazide using Cyclic Voltammetry and Galvanostatic Electrolysis
Authors: Beryl J Raja , Raj Xavier Joseph
Published: August 2018

Trifluoromethylation of isonicotinic acid hydrazide has been investigated in trifluoroacetic acid containing pyridine, triethylamine and sodium trifluoroacetate dissolved in acetonitrile on platinum and glassy carbon electrodes using cyclic voltammetry. LSVs for isonicotinic acid hydrazide in 0.1 M TFA/ Py/TEA/NaTFA in acetonitrile on platinum electrode show that there is no distinct oxidation peak for the oxidation of isonicotinicacid hydrazide within the voltammetric region of 0.0 to 1.6 V vs Ag and it gets oxidized anodically in the gas evolution region itself. TFA/ NaTFA medium shows slightly higher current density than the other two media for the oxidation of isonicotinic acid hydrazide. CVs for different concentrations of isonicotinic acid hydrazide show that anodic peak becomes broad and flat. It shows that severe adsorption of INAH/product takes place on the glassy carbon electrode during the voltammetry scanning. Galvanostatic electrolysis of INAH in TFA/Py/ACN medium at low current density on Pt shows good conversion with low selectivity.
A Storage Module Evaluation for the Hydrogen Fuel Cell on Toy Design
Authors: Pa P. S. , Lin S. H.
Published: August 2018

The problem of environmental pollution has become worse and worse as the demand for energy has grown. An important aim of modern science is a diligent search for non-polluting methods of energy production. The fuel cell is one of the most important power sources devised in the 21st century and has all the necessary characteristics for environmental protection. The technology is pollution-free and highly efficient, converting the chemical energy of hydrogen gas directly into electricity. The fuel cell can be regarded as a small-scale power plant. The flow of electricity will continue as long as there is a supply of hydrogen. At present the storage of hydrogen is the most important consideration and there is not much information about fuel cells readily available at this time. This study concerns the development of 'The Hydrogen Fuel Cell generates Electricity Module' and demonstrates this in the design and use of a toy. A systemized analysis of power operation using existing fuel cell products and a setup of 'The Hydrogen Fuel Cell generates Electricity Module' was made. The Taguchi Method was used to arrive at the best parameter combination between fuel cell and toy. The best combination of parameters obtained in this experiment provides a power line voltage of 3.0V. An assessment was made of the arrangement of a non-pressurized single fuel cell that will best suit the requirements for use in the toy whale used in this work. This will instill feelings of personal scientific accomplishment and give the toy making industry a new look at the same time. We hope this can be applied on a larger scale in the future to provide non-polluting power for many such applications.
Direct Growth of Vertically-Aligned Single-Walled Carbon Nanotubes on Conducting Substrates using Ethanol for Electrochemical Capacitor
Authors: Azam Mohd Asyadi , Fujiwara Akihiko , Shimoda Tatsuya
Published: August 2018

A massive growth of vertically-aligned single-walled carbon nanotubes (VA-SWCNTs) from aluminum oxide (Al-O)-supported Co catalyst and high purity ethanol was performed using alcohol catalytic chemical vapor deposition (ACCVD) technique. SWCNTs with 50-μm thickness were grown on the substrates via this technique. The Al metal layer of 20 nm thickness was thermally-oxidized for the production of Al-O, and 0.5 nm cobalt (Co) thin films was used as catalyst for the CVD process. The CNT growth was optimized using SiO2/Si substrates, and similar experimental condition was applied to the conducting substrates. The as-grown CNTs were characterized using Raman spectroscopy and electron microscopies for growth confirmation and for quality level investigation. Development of the catalyst nanoparticles and Al-O support layer was observed using atomic force microscopy (AFM) and transmission electron microscopy (TEM). The electrodes were fabricated using directly-grown VA-SWCNTs on SUS 310S, and were successfully used as an electrochemical capacitor. Electrochemical analysis using KOH aqueous electrolyte was performed by cyclic voltammetric (CV) and galvanostatic chargedischarge measurements; a maximum 52 Fg-1 specific gravimetric capacitance was obtained from the VA-SWCNT electrodes.
Electropolymerization of Indole-3-acetic Acid on Glassy Carbon Electrode for Sensitive Detection of Nitrite
Authors: Yang Yu Jun , Yin Xiangle , Yu Zhixin , Du Yapin , Li Weikun
Published: August 2018

Highly uniform and adhesive films of poly(indole-3-acetic acid) (p-IAA) were fabricated on the glassy carbon electrode (GCE) by electropolymerization of indole-3-acetic acid (IAA). The p-IAA modified GCE (p-IAA/GCE) was constructed to develop a promising amperometric sensor for the sensitive determination of nitrite. Field emission scanning electron microscope (SEM) and electrochemical techniques were used for the surface characterization of the modified electrode. It was demonstrated that p-IAA modified GCE (p-IAA/GCE) exhibited remarkable electrocatalytic activity towards the oxidation of nitrite with obvious reduction of overpotential. Under the optimal conditions, the linear range for the detection of nitrite was 5.0×10-7 to 5.0×10-4 M with a high sensitivity of 0.105 AM-1, and a low detection limit of 1.0×10-7 M (S/N = 3). The influence of various anions and cations on the nitrite detection has been studied. The proposed method was successfully applied in the detection of nitrite in sausage samples, and the results were consistent with those obtained by UV-vis spectrophotometric methods.
Shorting Effects of LiFePO4 Cathode in Lithium Ion Batteries
Authors: Wang Yan
Published: August 2018

Co3(PO4)2 or AlPO4 coating layers were formed on the surface of LiNi0.8Co0.15Al0.05O2 cathode material by in situ chemical method and calcination at 700°C to improve the electrochemical cyclability and structural stability during charge-discharge process of the cathode. The structure and electrochemical properties of the pristine LiNi0.8Co0.15Al0.05O2 cathode materials and the metal phosphate coated-cathode materials were investigated by X-ray powder diffraction, scanning electron microscopy, particle size analysis, Brunauer-Emmett-Teller method, cyclic voltammetry, and galvanostatic charge-discharge test. Co3(PO4)2-LiNi0.8Co0.15Al0.05O2 and AlPO4- LiNi0.8Co0.15Al0.05O2 cathode showed the improved reversibility compared with the pristine cathode material. It is attributed to the structural stability of metal phosphate coated LiNi0.8Co0.15Al0.05O2. In particular, Co3(PO4)2-LiNi0.8Co0.15Al0.05O2 showed a more stable rate capability than the pristine LiNi0.8Co0.15Al0.05O2 and AlPO4-LiNi0.8Co0.15Al0.05O2 at high C-rate.
Phosphotungstic Acid Modified Expanded PTFE based Nafion Composites
Authors: Pattabiraman K. , Ramya K.
Published: August 2018

Composite membranes have been prepared by impregnation of PFSI(perfluorosulphonic acid ionomer) solution (Nafion®) into the expanded polytetrafluoroethylene (EPTFE) matrix. The matrix was modified by Na/Naphthalene treatment and with phosphotungstic acid (PTA). The matrix modifications helped in reducing the contact angle thereby improving the impregnation process by reducing the hydrophobicity of the matrix. The fuel cell made with these composite membranes showed that the performance of PTA modified matrix is comparable to that of Na/ naphthalene modified matrix. Further the performances of matrix modified membranes were higher than that of the as received matrix-composites. PTA treatment offers a simple method of matrix modification to achieve high performance.
Preparation and Performance of High Activation Carbon Microbeads for Application of Supercapacitors
Authors: Bai Li , Wang Xingyan , Wang Xianyou , Zhang Xiaoyan , Long Wanmei , Wang Hong , Li Xiaoshuan
Published: August 2018

Carbon microbeads (CMB) were successfully prepared by glucose hydrothermal route in a stainless steel autoclave. The CMB was treated in concentrated nitric acid in order to gain the highly activated carbon microbeads (ACMB). The structure and surface morphology of as-prepared ACMB were characterized by scanning electron microscopy (SEM) and Fourier transform infrared spectrometer (FTIR), respectively. The electrochemical characteristics and capacitive behaviors of the ACMB were studied by cyclic voltammetry, current charge/discharge and cycle life measurements. The results show that the ACMB electrode has good electrochemical performance and the specific capacitance of ACMB is 291.9 F g-1 at a scanning rate of 1 mV s-1. Meanwhile, the specific capacitance of the button supercapacitor was as high as 75 F g-1 at a charge/discharge current density of 0.5 A g-1 and the loss of specific capacitance was nearly neglectable after 5000 cycles.
Annealing Effects on the Properties of Electrodeposited CdSSe Thin Films
Authors: Mahalingam T. , Dhanasekaran V. , Rajendran S. , Ravi G. , Ixtlilco Luis , Sebastian P. J.
Published: August 2018

The effect of post heat treatment on structural, morphological and optical properties of electrodeposited CdSSe solid solution thin films were studied using X-ray diffractometer (XRD), scanning electron microscopy (SEM), and UV-Vis-NIR spectrophotometer, respectively. X-ray diffraction patterns revealed that polycrystalline nature with hexagonal structure of CdSSe thin films. Also the microstructural properties are calculated tends to increase and the face centred hexagonal orientation of CdSSe thin film is enhanced significantly by increasing the annealing temperature. Scanning electron microscopic images revealed that the hexagonal shaped grains are occupying the entire surface of the film. The optical transmittance and absorption spectra were recorded in the range 400 to1100 nm. The band gap of the CdSSe thin films was found to decrease from 2.0 eV to 1.8 eV due to annealing temperature. The real part of the complex refractive index (n) and the imaginary part extinction coefficient (k) were calculated before and after annealing.
Oxygen Reduction Performance of Pt/TiO2-C Electrocatalyst prepared by Two-step Chemical Vapor Deposition
Authors: Huerta R.G. González , Valenzuela M.A. , García R. Vargas , Alonso-Vante N. , Velázquez M. Tufiño , Ruiz-Camacho B.
Published: August 2018

The low durability of Pt/C electro-catalysts in polymer electrolyte membrane fuel cells (PEMFC), e.g., as a result of carbon oxidation to CO2 in an acid medium, has been recognized as one of the most important hindrances to long-term stability. In this work, Pt electrocatalysts supported on TiO2-carbon and Vulcan carbon were prepared by the chemical vapor deposition method. The physical and electrochemical properties of Pt/TiO2-C and Pt/C electrocatalysts were investigated by the characterization techniques of XRD, TEM, CO stripping and cyclic and linear voltammetry. The prepared materials were electrochemically evaluated in the oxygen reduction reaction (ORR) in an acid medium at room temperature. The XRD results show crystalline fcc platinum formation. The mean particle size is between 2 and 4 nm with a spherical morphology. Pt/TiO2-C electrocatalysts showed a higher electrochemical active surface area and better activity results for the ORR compared with the Pt/C samples. The addition of TiO2 to the conventional Pt/C catalyst modifies the electronic properties affecting the oxygen adsorption and improving the catalytic activity for the oxygen reduction reaction.
Thermal Treatment Effects on Pd5Cu4Pt Electrocatalyst for the Oxygen Reduction Reaction in a PEM Fuel Cell
Authors: Martínez-Casillas D.C. , Gil-Esquivel O.A. , Solorza-Feria O.
Published: August 2018

The research is aimed to study the thermal treatment effects in the electrochemical activity of Pd5Cu4Pt electrocatalyst for the oxygen reduction reaction (ORR) in acid medium as well as on its performance as cathode electrode in a single Proton Exchange Membrane Fuel Cell (PEMFC). The electrocatalyst is synthesized by chemical reduction of PdCl2, CuCl2 and H2PtCl6 with NaBH4 in THF, and is characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Cyclic voltammetry (CV) and rotating disc electrode (RDE) are performed for electrochemical characterization in a 0.5 M H2SO4 at 25 ºC. Results of thermal treatment at 200 and 300 ºC in H2 atmosphere show a growth of nanocrystallyte particles and an enhancement of the crystallinity of the electrocatalyst. Shifts towards positive 2 θ XRD values are associated to the incorporation of elements inside the crystalline structure of the sample. Electrochemical results show a decrease in the electrocatalytic activity as the temperature of the thermal treatment increases. The maximum power density, Wmax of 350 mW cm-2 is achieved using Pd5Cu4Pt without thermal treatment with 0.8 mg cm-2 cathode electrocatalyst loading of the PEMFC. This result is attributed to the formation of new inactive-ORR phases on the electrocatalyst with the thermal treatment.
Nanostructured OMO type Manganese Oxide – as Novel Support for Palladium towards Electrooxidation of Methanol and Ethylene Glycol
Authors: Kannan Ramanujam , Karunakaran Kulandaivelu , Vasanthkumar Samuel
Published: August 2018

Octahedral molecular sieve type manganese oxide (OMO) was synthesized by the ultra sonic assisted hydrothermal method, and was subsequently used as supportive material for palladium (Pd) metal towards the electrooxidation of methanol and ethylene glycol. The Pd nanoparticles were coated on the OMO by insitu reduction method. Low quantity of 5% Pd metal was used and the electrocatalytic activity was studied. The prepared OMO and the OMO/Pd nanocomposite were characterized by powder X–ray diffractogram (XRD), Scanning Electron Microscopy (SEM), Energy dispersive X–ray spectroscopy (EDS) and electrochemical methods. These studies demonstrated that the OMO can act as a good catalyst supporting material. The OMO helps to enhance the catalytic activity of Pd metal by supplying the active oxygen, which is extracted from the electrolytic solution. The electrooxidation of EG shows improved catalytic activity.
A Comparative Study of the Electrooxidation of Ethylene Glycol on Transition Metal Electrodes in Alkaline Solution
Authors: Danaee I. , Jafarian M. , Sangachin A.A. Shahnazi , Gobal F.
Published: August 2018

Electrodes made of group VIII and IB metals were examined for their redox process and electrocatalytic activities towards the oxidation of ethylene glycol in alkaline solutions. The method of cyclic voltammetery (CV) and Open circuit potentials measurement (OCP) was employed. It is found that considerable electrooxidation current are observed for silver and copper but lower anodic overpotential for oxidation is obtained for gold and platinum. Oxide layer produced on the surface of all electrodes in alkaline solution under anodic scan participates in ethylene glycol electrooxidation. Oxidation current observed in the reverse scans for platinum and gold are higher than those observed in forward potential scan. Open circuit potential measurements have shown the interaction of ethylene glycol and electrodes.
High Surface Area Lithium Titanate Electrode for Li-ion Batteries
Authors: Tikekar Nishant M. , Lannutti John J. , Revur Ramchandra Rao , Sengupta Suvankar
Published: August 2018

A lithium titanate (Li4Ti5O12) anode composed of submicron fibers with nanosize grains was fabricated by electrospinning from spin dopes prepared from nanoparticles of lithium titanium oxide (Li4Ti5O12) and polyvinylpyrolidone (PVP) in a solvent. Optimal electrospinning conditions and solvent composition that could be electrospun into fibers under a variety of ambient conditions were determined. Pyrolyzing the electrospun fibers at high temperatures (700°C for 5 hours in air) and plasma-treating in oxygen (500 m Torr for 30 m) revealed a nano-size grain structure within the individual fibers. Electrochemical testing with metallic lithium as a reference electrode displayed promising capacities for three charging cycles. The C rates displayed complete charging when the charging time was at least 10 minutes. However, faster charging resulted in a loss of capacity to as low as 50% when charged in less than three minutes. This degradation appears to be triggered by trace amounts of a secondary phase introduced by standard purity precursors used for preparing lithium titanate. Evidence for this was found using x-ray fluorescence revealing the presence of iron and silicon oxides.
Oxygen Evolution Nickel Hydroxide Electrodes in a Ni-MH Battery Prototype
Authors: Becker M.D. , Cuscueta D.J. , Salva H.R. , Nieto F. Rodriguez , Ghilarducci A.A. , Visintin A.
Published: August 2018

The effect of cobalt in both alpha and beta phases on the oxygen evolution of nickel hydroxide was studied. The electrochemical properties of the oxygen evolution reaction on the positive nickel hydroxide electrodes were studied under conditions similar to those of a commercial Ni-MH battery. The presence of different kinds of defects in the structure of the active material was determined by XRD methods distorted and asymmetric reflections in the XRD patterns. Both the morphology of the active material and the additives influence the oxygen evolution potential and the electrochemical characteristics. The experimental results showed that the optimized prototype used in this work is suitable for evaluating several electrochemical parameters. It was shown that the electrode without cobalt exhibited the charging efficiency was 94% and those with cobalt exhibited a charging of 98%.
Effect of Nafion Loading in the Oxygen Electrode on Performance of the PEM-type Water Electrolyzer
Authors: Ma Hongchao , Yue Lixia , Dong Xiaoli , Fu Yinghuan , Liao Jianhui , Liu Changpeng , Xing Wei
Published: August 2018

The electrocatalyst layers of the oxygen electrode with various Nafion loading for water electrolyzer with polymer electrolyte membrane (PEM-type) were prepared, and the relationship between Nafion loading in the oxygen electrode and the performance of PEM-type water electrolyzer were examined by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and Steady-state galvanostatic polarization (GP). It is found that the appropriate Nafion loading in the oxygen electrode (i.e., 0.5 and 1.0 mg/cm2) can increase the electrochemically active area and decrease resistance of electrocatalyst layer. The decrease in working voltage for water electrolyzer with 0.5 and 1.0 mg/cm2 Nafion loading was 0.23 and 0.19 V at a current density of 1A/cm2, compared with that of water electrolyzer without Nafion loading (2.25V).
Simulation of Flow Field Pattern Influence on the Hydrogen Consumption in A PEMFC
Authors: Palacios M.J. , Perez-Hernandez A. , Sebastian P.J.
Published: August 2018

Simulations results are presented in this paper, which were obtained on investigating the effects of flow patterns on the hydrogen consumption in a proton exchange membrane fuel cell (PEMFC). In this study, a 3-D computational model was developed to investigate the influence of the flow and depth of the channels on hydrogen consumption. Simulation results showed the influence of depth in the distribution of hydrogen concentration. The flow channel pattern adopted in this study is the serpentine flow channel.
A Study on Electrochemical, Catalytic and Biological Properties of New Nickel Coordinated Schiff Base Materials
Authors: Jebamary S. Asha , Antony R. , David S. Theodore , Karuppasamy K. , Thanikaikarasan S. , Mahalingam T. , Eapen D.
Published: August 2018

Four new Schiff bases have been derived from the condensation of acenapthoquinone and naphthylamines in 1:2 molar ratios. These Schiff base ligands were used to synthesise novel mononuclear Ni(II) complexes with square planar geometry. The ligands and the complexes have been investigated by elemental analyses, spectroscopic methods (FT-IR and UV-Vis.,), molar conductance and magnetic susceptibility studies. The electrochemical properties of Ni(II) complexes have been studied by cyclic voltammetry technique. The catalytic efficacy of the complexes has been analysed in the oxidation of toluene to benzyl alcohol, using H2O2. Biological activities of these ligands and complexes were checked against selected bacterial strains (E. coli and S. Aureus).
Effect of Chitin Nanofibres on the Electrochemical and Interfacial Properties of Composite Solid Polymer Electrolytes
Authors: Karuppasamy K. , Thanikaikarasan S. , Balakumar S. , Thiravetyan Paitip , Eapen D. , Sebastian P.J. , Shajan X. Sahaya
Published: August 2018

Chitin nanofibres (CNF) are synthesized from a biopolymer chitin by ultra-pure chemical curing method. The nanocomposite solid polymer electrolytes (CSPE) based on PEO-LiBOB with chitin nanofibres as inert nanofiller are prepared by membrane hot-press method. The polymer membrane obtained is subjected to various electrochemical studies such as impedance analysis, cyclic voltammetry and compatibility studies. The crystalline behavior and structural changes in CSPE are investigated by means of XRD and FT-IR analyzes. The filler incorporated membrane shows better electrochemical properties as compared to filler free membrane. The addition of chitin nanofibre in polymer matrix enhances the ionic conductivity and achieves a maximum of 10-3.8 S/cm. Cyclic voltammetry study is used to know the electrochemical activity of prepared polymer electrolytes at ambient temperature. The compatibility studies reveals that the filler incorporated nanocomposite solid polymer electrolytes reduce the value of interfacial resistance (Ri) and it is better compatible with lithium interface.
Growth and Characterization of Electroplated Copper Selenide Thin Films
Authors: Ramesh K. , Bharathi B. , Thanikaikarasan S. , Mahalingam T. , Sebastian P.J.
Published: August 2018

Copper Selenide thin films have been prepared on indium doped tin oxide coated conducting glass substrates from an aqueous electrolytic bath consists of CuSO4 and SeO2 using potentiostatic electrodeposition technique. Deposition mechanism has been analyzed using cyclic voltammetry. X-ray diffraction pattern showed that the prepared films possess polycrystalline nature with hexagonal structure. Film composition and surface morphology showed that films with smooth surface and better stoichiometry are obtained under optimized condition. Band gap value of the deposited films is determined using optical absorption measurements. Variation of film thickness with time and its dependency on structural, morphological, compositional and optical properties are investigated.
Electrodeposition of ZnO for Application in Dye-sensitized Solar Cells
Authors: Tzec F. I. Lizama , Frutis M. A. Aguilar , Gattorno G Rodríguez , Oskam G.
Published: August 2018

ZnO has been electrodeposited from 0.5 M Zn(NO3)2 at pH 4.5 with and without polyethylene glycol (PEG) as additive. Cyclic voltammetry on FTO substrates reveals two electrochemical regimes, where reduction of nitrate and water are rate determining, respectively. ZnO films were galvanostatically electrodeposited as a function of the deposition current density: at low current densities, where nitrate reduction is rate determining, highly crystalline ZnO films were obtained, whereas amorphous ZnO films were obtained at higher current densities, where water reduction dominates. The amorphous films transform to crystalline ZnO upon sintering, and SEM images show that the presence of PEG results in a homogeneous film morphology. The films were used for the fabrication of dye-sensitized solar cells (DSSCs), resulting in solar cell conversion efficiencies of up to 1.4% for non-sintered ZnO films deposited at low current density (without PEG), while the best cells were obtained with films electrodeposited from the plating bath with 0.15 mM PEG with efficiencies of up to 1.8% for sintered films prepared at higher current density. These results illustrate that the presence of PEG in the plating bath optimizes the film morphology and, hence, the performance of ZnO-based dye-sensitized solar cells.
Effect of Two Anodic Materials and RuxMoySez as a Cathode Catalyst on the Performance of Two Singlw Chamber Microbial Fuel Cells
Authors: Vázquez-Larios A.L. , Solorza-Feria O. , González-Huerta R. de G. , Ponce-Noyola M.T. , Barrera-Cortés J. , Rinderknecht-Seijas N. , Poggi-Varaldo H.M.
Published: August 2018

The objectives of this work were to evaluate (i) the application of a bimetallic chalcogenide, RuxMoySez, as an oxygen reduction reaction (ORR) catalyst and (ii) the effect of the type of two anodic materials on the performance of two microbial fuel cells (MFCs). A single chamber MFC-T was built with a plexiglass cylinder, the two extreme circular faces were fitted with PEM-cathode assemblage, i.e., left and right faces. The anode consisted of 65 small triangular pieces of graphite filling the anodic chamber. A second MFC-C had a ‘sandwich’ arrangement anode-PEM-cathode. The cathodes were made of ?exible carbon-cloth containing catalysts loading of 1mg/cm2 RuxMoySez or 0.5mg/cm2 Pt. Power derived by cell T with cathode chalcogenide catalyst was 43% inferior to that of a similar cell with Pt although the cost of the first catalyst is significantly lower than that of Pt, i.e., 73% lower. Finally, application of graphite anode made of small triangular pieces significantly improved the performance of a MFC-T that used RuxMoySez as a cathodic catalyst for ORR.
Synthesis of Unsupported Pt-based Electrocatalysts and Evaluation of Their Catalytic Activity for the Ethylene Glycol Oxidation Reaction
Authors: Chávez Villanueva A. F. , Ramirez Adriana M. , Gutiérrez G. Vargas , Torres L. A. , Varela F. J. Rodríguez
Published: August 2018

In this work, unsupported Pt, Pt-Ru (1:1 wt. % Pt:Ru ratio) and Pt-CeO2 (1:1 wt. % Pt:CeO2 ratio) electrocatalysts were synthesized and evaluated as anodes for the ethylene glycol oxidation reaction (EGOR) in out in H2SO4 electrolyte. The nanomaterials were prepared by slowly dropping the precursors in a NaBH4 solution, in a reduction process of 10 min. Analysis by XRD showed the formation of polycrystalline electrocatalysts, while the chemical composition characterization indicated a ratio between the different elements in the bimetallic materials close to the stoichiometric value. Selected area electron diffraction patterns evaluation carried out in the TEM apparatus helped in the identification of Pt (1 1 1) in the three anodes, Ru (1 0 0) in Pt-Ru, and CeO2 (1 1 1) in Pt-CeO2, confirming the formation of Ru and CeO2 phases. The results from the electrochemical characterization by Linear Scan Voltammetry (LSV) showed that the Pt-Ru material possess a higher mass catalytic activity for the EGOR, followed Pt-CeO2, compared to Pt-alone. The nano-sized Pt-Ru and Pt-CeO2 anodes demonstrated a high electrochemical stability in accelerated potential cycling tests, with very low surface area losses in the hydrogen adsorption/desorption region after 500 polarization cycles. The results indicated that the bimetallic electrocatalysts are candidate anodes for Direct Ethylene Glycol Fuel Cells.
Oxygen Reduction Reaction (ORR) on a Mixed Titanium and Tantalum Oxy-nitride Catalyst Prepared by the Urea-based Sol-gel Method
Authors: Seifitokaldani A. , Perrier M. , Savadogo O.
Published: August 2018

The electrochemical stability and activity of different compositions of titanium and tantalum oxy-nitride nano-catalysts were investigated for the oxygen reduction reaction (ORR). A new sol-gel method was used to produce a nano-powder mixture of Ti and Ta oxynitride from their alkoxides using urea as a nitrogen source. The precursors prepared by the sol-gel method were annealed in a N2 + 3% H2 atmosphere at determined temperatures (500, 700 and 900 °C) inside a silica tube furnace. X-ray diffraction results proved that by using this method a considerable amount of nitrogen was inserted into the catalyst structure at a relatively low temperature. Energy dispersive spectroscopy showed that the prepared catalyst should be oxidized carbonitride of titanium and/or tantalum. Heat treatment had a major effect on the onset potential by changing the crystallinity of the catalyst, so that the onset potential of titanium oxynitride increased from ca. 0.05 V to 0.65 V vs. NHE by increasing the temperature from 500 to 700 °C. Increasing the Ta concentration also led to a higher onset potential but lower ORR current. For instance, the onset potential for the ORR for tantalum oxynitride heat treated at 700 °C was ca. 0.85 V vs. NHE while this value was ca. 0.65 V vs. NHE for titanium oxynitride. However, the ORR current was 100 times smaller in tantalum oxynitride, most likely because of a low electrochemically active surface area. Electrochemical measurements suggested that an appropriate composition of titanium and tantalum was required to have both a good onset potential and ORR current by improving the catalytic activity and increasing the active surface area and electrical conductivity.
Effective Electro-Fenton Degradation of Reactive Black 5 Dye using Modified Electrode with Cu-Zeolites
Authors: Oliver-Tolentino Miguel A. , Jiménez-Álvarez Elmer , Martínez-Ortiz María De Jesús , García-Báez Efrén , Franco-Hernández M. Olivia , Guzmán-Vargas Ariel
Published: August 2018

The electrocatalytic production of hydroxyl radical (HO•) on the surface of zeolite modified electrode (ME) employing Cu-Zeolites (ZSM5 and β) with different theoretical ionic exchange (15 and 100%) was investigated (ME/Cu-Zeolites). The i-E characteristic of ME/Cu-ZSM-5 presented the faradic process associated to redox couple Cu2+/Cu+. On the other hand, voltammetric studies showed that in presence of H2O2, the cathodic peak current of ME/Cu-Zeolites increases followed by a decrease in the corresponding anodic current. This suggested that hydroxyl radical was produced by a cooperative effect of the acidic properties of zeolite and copper that acts as a redox mediator on the electrode surface via an electrocatalytic mechanism. Experiments of degradation using azo dye Reactive Black 5 as probe molecule exhibited that the concentration of azo dye decreased in the time, this confirms the formation of hydroxyl radical on the surface of modified electrode; kinetics parameters demonstrated that the ME/Cu- β with 15% of ionic exchange presented the highest catalytic activity.
Properties of Polystyrene/Acrylic Acid Membranes After Sulphonation Reactions
Authors: Benavides R. , Oenning L. W. , Paula M. M.S. , Da Silva L.
Published: August 2018

Sulphonation reaction in styrenic membranes is a common method used to graft ionic groups needed to enhance proton conductivity in polymeric electrolytes (PEM). A synthesized copolymer of styrene and acrylic acid (94/6 % mol) was partially crosslinked using a trifunctional monomer, trimethylolpropane trimethacrylate (TMPTMA) (0.01% mol), like a crosslinking agent. The obtained material was subjected to different sulphonation reactions in order to prepare several PEM membranes. The sulphonation reactions used sulphuric acid (H2SO4, 98%) at 50, 75 and 100 %molar ratio considering amount of styrene rings, during 1 and 2 hours of reaction time. Fouriertransformed infrared spectroscopy (FTIR) spectra were obtained to identify specific chemical groups in these materials. Thermogravimetric analysis (TGA) and Dynamic Mechanical Analysis (DMA) were used to evaluate the thermal stability and mechanical effects after sulphonation reactions. Water absorption and its effect on proton conductivity by means of Electrochemical Impedance Spectroscopy (EIS) were also evaluated. FTIR spectra show characteristic bands corresponding to sulphone groups within macromolecular structure. Sulphonating agent concentration and/or sulphonation time induce higher glass transition temperatures and no changes in thermal stability when comparing with the no sulphonated material. Latter condition also allows higher water absorption and an enhancement in proton conductivity.
Effect of X-ray Irradiation on Dielectric Properties of Polymer Electrolytes Complexed with LiCF3SO3
Authors: Vani C. Vijil , Thanikaikarasan S. , Mahalingam T. , Sebastian P. J. , Verea L. E. , Shajan X. Sahaya
Published: August 2018

Solid polymer electrolytes of polyethylene oxide (PEO) embedded with LiCF3SO3 was prepared and subjected to X-ray irradiation of different dosages (1.5 to 6 Gy). Ionic conductivity and dielectric studies were made over a frequency range of 100 Hz to 490 KHz. A little increase in ionic conductivity was noted for the sample irradiated for 1.5 Gy and the equivalent circuit remained unaltered for irradiated samples. Remarkable increase in dielectric constant was found for the irradiated samples. It was found that irradiation improved the dissolution of lithium salt and increased the polymer/Lithium interaction and thus improved the polarizability of the electrolyte. The frequency of hopping and liberation of free lithium ions were found altered by irradiation and hence the given dosage was found to have an optimum value in concern with the ionic conductivity of the electrolyte.
Growth and Characterization of Electroplated NiO Coatings
Authors: Bharathi B. , Thanikaikarasan S. , Kollu Pratap , Chandrasekar P. V. , Mahalingam T. , Lxtlilco Luis
Published: August 2018

Thin films of NiO have been prepared using potentiostatic electrodeposition technique from an aqueous electrolytic bath containing NiSO4. Deposited films have been characterized using x-ray diffraction, scanning electron microscopy and energy dispersive analysis by x-rays. X-ray diffraction patterns showed that the prepared films possess polycrystalline nature with face centered cubic structure. Surface morphology and film composition showed that films with better stoichiometry and smooth surface are obtained at optimized growth condition. Optical absorption analysis showed that the prepared films possess direct band gap value around 3.46 eV.
Electroanalysis of Diazepam on Nanosize Conducting Poly (3-Methylthiophene) Modified Glassy Carbon Electrode
Authors: Lakshmi A. , Gopu G. , Thanikaikarasan S. , Mahalingam T. , Alvarez Peggy , Sebastian P. J. , Vedhi C.
Published: August 2018

A glassy carbon electrode (GCE) was modified with nanosize poly (3-methylthiophene) (P3MT) and used for the sensitive voltammetric determination of diazepam. The cyclic voltammetric response of the bare GCE was compared with the P3MT modified electrode. Electrochemical impedance response of diazepam on modified GCE was studied by various concentrations of diazepam from 0.2 μM to 0.6 μM. The poly (3-methylthiophene) modified glassy carbon electrode (P3MT/GCE) can greatly enhance the peak currents and the detection sensitivity of diazepam under optimal conditions. The quantitative analysis of diazepam was made by the DPSV method. The experimental results showed that the peak current increased with the increase in concentration of diazepam. A calibration was made, which indicated the linear dependence of peak current with concentration (ip = 13.31Conc. + 0.4359R2 = 0.9948) in the range od determination and ot was found to be good between 0.2 and 1.07 μg/L. The limit of detection was 0.1μg/mL. The reproducibility of the stripping signal was realized in terms of relative standard deviation for 6 identical measurements and was found to be 2.6%. The effect of interference of different cations and anions on the oxidation of diazepam was studied. Real sample analysis of diazepam was also studied through DPSV.
Study of Calcination Temperatures of Pillared Bentonite to the Performance of Cyanide Biosensor and its Application to Determine Cyanide in Cassava
Authors: Bijang Catherina , Wahab Abd. Wahid , Ahmad Ahyar , Taba Paulina
Published: August 2018

Amperometric biosensors for determining cyanide which are accurate, cheap and practical have been made. The biosensor used a modified bentonite as a electerode membrane. Current measured by a potensiostat with a Cyclic Voltametry method. Study of calcination temperature on pillarization of bentonite and thickness of bentonite membrane was conducted to get electrode with the best performance. The performance was tested using : Cathecol linearity, maximum inhibition percentage, cyanide linearity, detection limit and sensitivity. The data showed that electrode with membrane of bentonite pillarized at 250 C and the thickness is 5 mg/mL had the best performance.
Influence of pH on the Electropolymerisation of 2-Aminophenol and 2-Aminobenzyl Alcohol
Authors: Barham Ahmad S.
Published: August 2018

The electrochemical oxidation and polymerisation of 2-aminophenol and 2-aminobenzyl alcohol in aqueous solutions of different pH values has been studied. Polymer films of the studied monomers on gold electrodes were synthesized. The behaviour of both monomers is quite different, illustrating the resonance effect of the hydroxyl group being bound directly to the benzene ring for 2-aminophenol. For each compound it is shown that oxidation in acidic solutions is most difficult due to the protonation of the amine group. These polymer films can be used for applications such as corrosion protection and as structures from which textured electrodes, microelectrode arrays for example, can be generated.
Electrophoretic Deposition and Physicochemical Characterization of Al2O3-NiO Composite Materials
Authors: Bintou O. , Savadogo O.
Published: August 2018

Al2O3-NiO composites were fabricated by electrophoretic deposition (EPD). Suspensions were prepared from the mixture of Al2O3 and NiO powder in a mixed ethanol-water electrolyte and were stabilized with acetic acid. The effects of the NiO content, sintering temperature and the deposition parameters such as the EPD applied voltage and deposition time on the coating weight, microstructure and crystallinity of final composites were studied. Due to the positive charge of Al2O3 and NiO in suspension in the mixed ethanol-water solvent, samples were deposited on the cathode and they were not affected by the possible solvent electrolysis. Coatings with defect-free microstructure were then obtained. These investigations have revealed that the deposits weight gain increases linearly with NiO content and theirs thickness was controlled by adjusting the NiO content and/or the time of the deposition. By increasing NiO content, the distribution of NiO nano-particles in Al2O3 matrix became more homogenous forming thereby an interconnected network like-microstructure which inhibits the grain growth of Al2O3. This illustrates clearly the advantage of EPD for the synthesis of Al2O3-NiO particles. XRD studies have revealed that apart from Al2O3 and NiO, a cubic nickel spinel (NiAl2O4) like phase is formed in the Al2O3-NiO composite. The increase of the applied voltage has resulted in a serious reduction of the deposit weight gain and also to the degradation of their microstructures particularly when the NiO content is lower than 40%.
Fabrication of ZnO Nanorods on Silicon Substrates by Sol-gel Hyrdothermal Methods
Authors: Shyu Yow-Chyun , Lin Min Han , Lin Shang-Ren , Tsai Shang Lin , Chen Chin Pang , Sheu Meng-Lieh , Chen Hsiang
Published: August 2018

ZnO nanorods were deposited on silicon substrate using sol-gel hydrothermal methods. The seed layer was first grown by sol-gel methods and then annealed at temperatures of 300ºC, 400ºC, 500ºC and 600ºC. Multiple material and optical analyses including field-emission scanning electron microscope, energy dispersive X-ray spectroscopy, X-ray diffraction, photoluminescence spectra, and Raman spectra were conducted to examine the growth orientation and material properties. Results indicate that the ZnO nanorods annealed at a proper temperature of 400ºC could enhance orientation and material quality.
A Simple Approach to Prepare Metal Oxides Supra-Structures for LIBs
Authors: Padashbarmchi Zahra , Hamidian Amir Hossein , Noonan Owen , Khorasani Nematolah , Kazemzad Mahmood
Published: August 2018

A variety of materials have been investigated as potential electrode materials for LIBs. Electrodes including Fe, Co, Ni or Cu have more Lithium ion storage capacity (more than 600 mAh/g) comparing to graphite (about 372 mAh/g). Recently, much effort has been focused toward achieving 3-dimensional hollow spheres with high surface area and porous for better capacity performance. In this study a simple spray drying approach has been introduced to synthesize porous CuO and Co3O4 microspheres. The results revealed that uniform structures of the nanoparticles microspheres were achieved. Then their cyclic performance were analyzed and compared to their commercial counterparts. The porous CuO microspheres and Co3O4 microspheres exhibited high capacity retention (86.2% of the discharge capacity of the second cycle after 60 cycles) and (89.8% of the discharge capacity of the second cycle after 40 cycles) at a current density of 400 mA/g, respectively. The excellent electrochemical properties could be attributed to their unique porous structures. The electrochemical results showed that microspheric electrode materials are able to manifest superior electrochemical properties compared to their commercial counterparts.
Synthesis, Crystal Structure, and Fluorescence Properties of Dinuclear and Tetranuclear Zinc(II) Complexes Based on 2-(2’-Hydroxyphenyl)-2-oxazoline
Authors: Zhou Yuan , Liu Qiming , Zhang Yuao
Published: August 2018

Two new zinc(II) complexes have been prepared by reaction of 2-(2’-Hydroxyphenyl)-2-oxazoline(Hoz) with Zn(acac)2 and ZnCl2 respectively. The complexes are characterized by IR and X-ray crystallography. Complex 1 is dinuclear zinc structure bridged by the oxygen atoms from oz- ligand and acac- ligand as terminal chelating ligand. Complex 2 is tetranuclear zinc structure bridged by both μ2-oxygen from oz- ligand and μ3-methoxide. 1 crystalizes in P21 space group with crystallographic parameters: a=9.3842Å19), b=13.5840 Å30), c=11.1380 Å20), β=96.250°(30). 2 crystalizes in P-1 space group with crystallographic parameters: a=9.5517Å(19), b=11.1234Å(22), c=11.1826Å(22), α=102.820°(30), β=114.988°(30), γ=100.806°(30). The UV absorption and fluorescence emission spectra are measured on the methanol solution and solid state of complex 1 and it shows strong luminescence.
Effect of Growth Solution Concentration on the Performance of Boron Doped ZnO Dye-sensitized Solar Cell (DSSC)
Authors: Rahman M. Y.A. , Umar A. A. , Roza L. , Samsuri S. A.M. , Salleh M. M. , Iwantono I. , Tugirin Tugirin
Published: August 2018

Synthesis parameter plays important role in modifying physical property of metal oxide films which serve as photoanode in dye-sensitized solar cell (DSSC). This paper reports the synthesis of boron doped ZnO nanostructures via seed mediated growth hydrothermal technique and their application as photanode in DSSC. The growth process was carried out at various solution concentrations, 0.1, 0.2, 0.3 and 0.4 M. The solution contains 1 % wt. dimethyl borate as boron source, hexamethylenetetramine (HMT) surfactant and zinc nitrate (Zn(NO3)2). The samples are crystalline with wurtzite phase. The morphological shape of the samples changes with the growth solution concentration. The optical absorption increases as the concentration increases. However, the band gap does not significantly change with the concentration. The DSSC utilizing the ZnO sample prepared at 0.1 M solution performs the best photovoltaic parameters with the JSC of 0.969 mA cm-2, FF of 0.48 and η of 0.222%, respectively since it shows the highest absorption and lowest photoluminescence in visible region.
Permittivity Study of a CuCl Residue at 13–450 °C and Elucidation of the Microwave Intensification Mechanism for Its Dechlorination
Authors: Zhanyong Guo , Fachaung Li , Guang Su , Demei Zhai , Fang Cheng , Shaohua Ju , Jinhui Peng
Published: August 2018

Permittivity is a vitally important parameter for describing the absorbing and heating characteristics of a material under microwave irradiation, and it is also strongly dependent on temperature. However, the literature contains little information on this topic and even less particular permittivity data at elevated temperatures. In this paper, the permittivity of a CuCl residue at temperatures from 13 to 450 °C at 2.45 GHz was measured using the cavity perturbation method. The relationship of its real part (ε′) and imaginary part (ε″) with temperature (T) was deduced. In addition, the temperature-dependent tangent (tan δ) and the penetration depth (d) of microwaves into the material were calculated. The results of the permittivity study show that the dielectric constant (ε′) of the CuCl residue increased linearly with increasing temperature. In contrast, the dielectric loss factor (ε″) and loss tangent first maintained on a steady value between 13 and 300 °C and then substantially increased from 300 to 450 °C. The positive interaction of the dielectric property and temperature showed the reasonableness of our earlier metallurgy process, where the CuCl residue for dechlorination was roasted at 350–450 °C under microwave irradiation.
Investigation on the Time Error of Detonation Acoustic in Process of Formation and Propagation
Authors: Xu Gui-yang , Wang Chun-guang , Hu Shao-qing , Gong Jian-Liang , Deng Zhe
Published: August 2018

The time error of detonation acoustic in process of detonation formation and propagation in a multi-cycle gas-liquid two-phase pulsed detonation engine is experimentally investigated. Results from the tests show that before the detonation wave escapes through the open-end of PDE tube, the maximum average arrival time error of detonation acoustic is achieved in the process of overdriven detonation. After detonation wave exists of PDE tube, arrival time error at 0 deg is greater than the other directivity angles in all distances and increases dramatically first and then almost stays at a certain value. The filling fraction has a major impact on the time error of detonation acoustic. With filling fraction increasing, there are increases in arrival time error and interval time error. Arrival time error with the highest filling fraction at 30 deg is much greater than other filling fraction. The convergent nozzle exhibits a marked suppression in the time error of detonation acoustic, where the maximum reductions of 62.02 percent and 56.13 percent are obtained in arrival time error and interval time error respectively.