Physical Sciences and Mathematics Commons^™

Electrochemical Preparation And Photocatalytic Performance Of Lanio3/Tio2 Nanotube Arrays, Cheng Gong, Ze-Yang Zhang, Si-Wan Xiang, Lan Sun, Chen-Qing Ye, Chang-Jian Lin

Journal of Electrochemistry

The LaNiO₃/TiO₂ nanotube arrays were prepared by pulse electrodeposition combined with high temperature annealing. The LaNiO₃ nanoparticles modified on the TiO₂ nanotube arrays had small particle size (< 10 nm), uniform distribution and controllable loading. Some LaNiO3 nanoparticles were deposited inside the TiO₂ nanotubes. The UV-visible absorption spectra displayed that the absorption band edge of LaNiO₃/TiO₂ nanotube arrays was obviously red-shifted as compared with that of TiO₂ nanotube arrays, and the visible light absorption was enhanced significantly. The photocatalytic degradation results of rhodamine B (RhB) under visible light showed that the LaNiO₃/TiO₂ nanotube arrays prepared by pulse electrodeposition for 500 cycles had …

Transient Electrochemical Surface-Enhanced Raman Spectroscopic Study In Electrochemical Reduction Of P-Nitrothiophenol, Yun Ling, Jing Tang, Guo-Kun Liu, Cheng Zong

Journal of Electrochemistry

P-nitrothiophenol (PNTP) is one of the most common probe molecules studied by surface-enhanced Raman spectroscopy (SERS). The research in electrochemical reduction behavior of PNTP will help understanding the mechanism for the nitrobenzene reduction. In this paper, we used transient electrochemical surface-enhanced Raman spectroscopy (TEC-SERS) to study the SERS of PNTP with cyclic voltammetry and chronoamperometry on gold electrodes. The results show that the TEC-SERS provide a time resolution that equals the transient electrochemical methods, and we concluded that the reaction was so quick that we did not observe the spectral information of intermediate species described in the literatures with a …

Quantitative Detection Of Levofloxacin Hydrochloride By Differential Pulse Stripping Voltammetry With Electrodeposited Bismuth Film Electrodes, Zi-Ying Guo, Zuo-Peng Li, Jiang Li, Jian-Guo Zhao, Feng Feng

Journal of Electrochemistry

In this study, differential pulse stripping voltammetry was developed for the quantitative detection of levofloxacin hydrochloride indirectly. Levofloxacin hydrochloride contains organic amine, which can be precipitated upon interaction with Zn(SCN)₄^2-. By means of differential pulse stripping voltammetry, the concentration of Zn²⁺ can be determined using an in-situ formed bismuth film electrode, which allows determining indirectly the amount of levofloxacine hydrochloride. The linearity equation, I = 1.1401c - 0.5309 with the correlative coefficient R = 0.9979, was presented in the experiment. The results showed that this approach is very sensitive, having a limitation of detection of 3.18 …

Polyaniline Coated Hollow Sulfur Prepared Using Sublimate 2,4,6-Tri(Propan-2-Yl)-1,3,5-Trioxane As Template For Sulfur Electrode, Zhang-Feng Li, Xiao-Rui Wang, Wen-Sheng Tian, Jin-Ze Yang, Ping Zhang, Li-Ping Ma, Yang Chen, Xiao-Li Cui, Zhi-Yu Jiang

Journal of Electrochemistry

An advance method for preparing polyaniline-coated hollow sulfur material using sublimate material ADD(2,4,6-tri(propan-2-yl)-1,3,5-trioxane) as a template was developed for lithium-sulfur battery. At first, the smashed ADD particles were coated by a sulfur layer through the reaction of Na₂S₂O₃ with diluted HCl. Then polyaniline layer was coated again on the surface of sulfur layer through the reaction of aniline with (NH₄)₂S₂O₈. After being dried at 60 ^oC for 12 h, the ADD in such a composite evaporated totally, and resulted in the formation of polyaniline-coated hollow sulfur …

Electrochemical Determination Of Trace Copper Ions In Drinking Water Source, Jing-Ji Peng, Hong Zheng, Yi-Song Zou, Guo-Kun Liu, Dong-Xing Yuan

Journal of Electrochemistry

Aiming at the on-site and quick safety evaluation of the dissolved trace copper ions (Cu²⁺) in drinking water source, an electrochemical detection platform was developed on the basis of the square wave anodic stripping voltammetry using the gold nanoparticles (Au NPs) modified glassy carbon electrode, where Au NPs were deposited via electrochemical cyclic voltammetry. The proposed method displayed the limit of detection as low as 1.3 μg·L^-1 in the linear range of 2 ~ 50 μg·L^-1. The proposed method was applied to the determination of Cu²⁺ in the midstream of Minjiang River, one of …

Bipolar-Membrane Electrodialysis Method To Treat Industrial High Saline Perfume Wastewater, Jian Zhang, Dong-Fang Niu, Shuo-Zhen Hu, Xin-Sheng Zhang

Journal of Electrochemistry

Large amount of organic saline wastewater is generated from various chemical industries. The contents of organic saline wastewater are more and more complicated as they are created from different types of industries. Directly discharging the organic saline wastewater without pre-treatment can generate severe environmental problem and waste useful resources. It is necessary to use an economical method to treat the organic saline wastewater and recover the salt into useful materials to achieve resource reuse. Bipolar-membrane electrodialysis (BMED) is one of the methods that can remove salt from the wastewater and convert it into certain acid and base with higher value …

Study On Electro-Sorption Of Heavy Metals And Sulfamethoxazole On Activated Carbon Fibers, Wen-Jun Zhao, Bing-Xin Jia, Ya-Nan Zhang, Jiu-Nian Guan, Jiao Qu, Ying Lu

Journal of Electrochemistry

To study the optimal removal condition, adsorption mechanism and comparative analysis of the three typical cationic pollutants, i.e., Zn(II), anionic pollutant Cr(VI) and molecular pollutant sulfamethoxazole (SMX), using self-made upflowed electro-sorption device for adsorptions of above three pollutants by modified activated carbon fiber were researched. The activated carbon fiber (ACF) was modified by hydrochloric acid. The ACF morphology and structure before and after modification were characterized by SEM, BET and FTIR. The characterization results show that the modified ACF had fewer surface impurities than the modified surface and the gully is more obvious, the specific surface area was increased by …

Electrochemical Sensor Based On Magnetic Electrode Modified With Magnetic Molecularly Imprinted Nanoparticles Immobilized Hemoglobin For Determination Of Hydrogen Peroxide, Yang Yuan, Jia-Xin Wang, Yu-Hua Cao

Journal of Electrochemistry

In this work, the surface-imprinted technique was used to prepare magnetic hemoglobin (Hb) imprinted nanoparticles, using Fe₃O₄@SiO₂ NPs as the carrier, Hb as the template molecule, and tetraethyl orthosilicate (TEOS) as the imprinted polymer monomer. The nanoparticles had a core-shell structure, with magnetic Fe₃O₄ NPs as the core and Hb imprinted polymers as the shell. Therefore, Hb could be concentrated and fixed on the surface of the magnetic imprinted nanoparticles (MMIPs NPs). Furthermore, MMIPs NPs were immobilized with chitosan (CS) on the surface of a magnetic electrode to constitute Hb enzyme-like biosensor …

Hydrogen Production Of Microbial Electrolysis Cell Using Scrap Metal Net As Cathode And The Analysis Of Microbial Community Structure In Anode, Hong-Yan Dai, Hui-Min Yang, Xian Liu, Xiu-Li Song, Zhen-Hai Liang

Journal of Electrochemistry

In order to find high quality and low price hydrogen catalyst, a scrap metal net was used as single-chamber microbial electrolytic cell (MEC) cathode, and its hydrogen production performance was investigated at different applied voltages. Meanwhile, the microbial community structures of original aerobic activated sludge, MFC and MEC anode microbes were analyzed by 16S rDNA amplicon sequencing technology. As the applied voltage increased, the maximum current density was increased and the running time was shortened. At an applied voltage of 0.7 V, the hydrogen production and electrical energy efficiency obtained with scrap metal mesh cathode MEC were, respectively, 0.330±0.012 m …

Ionic Liquid Assisted Synthesis Of Porous Carbons From Rice Husk For Supercapacitors, Han-Fang Zhang, Feng Wei, Jian Sun, Meng-Ying Jing, Xiao-Jun He

Journal of Electrochemistry

It is still a challenge to prepare carbon materials with high specific surface area at low cost from renewable resources. Herein, the authors report an efficient approach to synthesize porous carbons (PCs) from rice husk with ionic liquid (1-butyl-3-methylimidazolium hexafluorophosphate (BMIMPF₆)) as a template and an activation agent. The as-made PCs featured the high specific surface area up to 1438 m²·g^-1. As electrodes for supercapacitors, PCs showed a high specific capacitance of 256 F·g^-1 at 0.05 A·g^-1 in 6 mol·L^-1 KOH aqueous electrolyte and a good rate performance of 211 F·g …

An Aptasensor Based On Aunps/Pani/Tnts Nanocomposite For Electrochemical Detection Of Tobramycin, Yong-Ling Nong, Ni-Na Qiao, Ying Liang

Journal of Electrochemistry

A novel well-constructed electrochemical aptamer-based sensor for the detection of tobramycin was presented, using differential pulse voltammetry (DPV) as a detection technique and methylene blue（MB） as an electrochemical indicator. A glassy carbon electrode modified with a nanocomposite of Au nanoparticles/polyaniline/titania nanotubes (AuNPs/PANI/TNTs) was constructed as the electrode scaffold. The nanocomposite was characterized by transmission electron microscopy and X-ray photoelectron spectroscopy in detail. The results of cyclic voltammetry and electrochemical impedance measurements demonstrated that the AuNPs/PANI/TNTs nanocomposites can improve greatly the electron transfer on the interface. For the detection of tobramycin, the DPV results showed a linear relationship between the current …

Effects Of Al-Doping On Properties Of Ni-Rich Cathode Materials Employing Different Aluminum Sources, Dan-Feng Wang, Yi-Xiao Li, Wei-Li Wang, Yong Yang

Journal of Electrochemistry

In order to investigate the effects of Al-doping on the structure, morphology and electrochemical performance of Ni-rich layered oxides, the NCA cathode materials with a nominal chemical formula of LiNi_0.8Co_0.15Al_0.05O₂ were prepared by two methods with different aluminum sources. One was the solid phase method: the precursor (Ni_0.84Co_0.16(OH)₂) prepared by co-precipitation was mixed with lithium and aluminum source (nano-Al₂O₃ or Al(NO₃)₃) thoroughly, and calcined at 780 ℃ for 15 h under an oxygen atmosphere. The other was the co-precipitation method: …

Electrochemical Properties Of Sulfur In Different Carbon Support Materials, Bo Zhang, Jia Liu, Xiao-Chen Liu, De-Jun Li

Journal of Electrochemistry

In order to investigate the effect of carbon structure on electrochemical performance of sulfur/carbon composite in lithium-sulfur battery, in this paper, sublimation sulfur was incorporated into three types of carbon materials, namely, graphene, carbon black and porous carbon. The three sulfur/carbon composites were characterized by scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET), and X-ray diffraction (XRD) techniques, and their electrochemical performances were also studied. The results showed that the sulfur/porous carbon composite offered an initial discharge capacity of 1623.2 mA·h·g^-1 and remained 845 mA·h·g^-1 after 100 cycles. Compared with graphene and carbon black, the mesopores and micropores in porous …

Electrochemical Behaviors Of Azopurine On Gold Electrodes, Ming-Xue Li, Hang Shi, Jia Liu, Meng Zhang, Jian-Zhang Zhou, De-Yin Wu, Zhong-Qun Tian

Journal of Electrochemistry

In this paper, we studied the electrochemical behaviors of azopurine on polished gold electrodes with cyclic voltammetry (CV). On the basis of analyzing scan rate and peak current, it was supposed that the redox process belonged to a reversible process controlled by adsorption in 0.2 mol·L^-1 PBS (pH = 4.0 ~ 10.0) solutions. The potentials of redox peaks moved more negatively with increasing pH value. This proved that the H⁺ proton has participcted in the electrochemical reaction. The further data analysis and the calculation of surface adsorption excess demonstrated that the reaction was a two-proton and two-electron process. …

Morphology Controlled Preparations And Electrochemical Properties Of Znco2O4 Electrode Materials For Supercapacitors, Yue-Shen Zhou, Meng Li, Shuang Wu, Zhao-Lei Li, Yan-Min Gao

Journal of Electrochemistry

In this work, hydrothermal reaction and high temperature were used to grow ZnCo₂O₄ active materials on Ni foam. The crystal stuctures and surface morphlogies of four samples were investigated by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). The electrochemical performances were characterized by cyclic voltammetry (CV)、galvanostatic charge/discharge (GCD) testing and electrochemical impedance spectroscopy (EIS) on an electrochemical station. It can be seen that active materials tended to form denser stuctures with an increasing amount of NH₄F in the solution system and four different morphologies of ZnCo₂O …

Electrochemical Cycling Stability Of Polyaniline Films In Different Color Ranges, Kun Xu, Kai-Ling Zhou, Hao Wang, Jing-Bing Liu, Hui Yan

Journal of Electrochemistry

The electrochromic behaviors of polyaniline films were investigated by potential step and cyclic voltammetry coupled with UV viscosity photometer. The polyaniline films show colorful changes from pale yellow to green and then to blue. Electrochromic stability, electrochemical behavior, coloring performance, optical properties and surface formations of the produced films were studied in detail. The working electrode was the flexible PANI electrode, and the counter electrode and the reference electrode were a platinum sheet and Ag/AgCl, respectively. The in situ optical transmittance of the PANI film at 650 nm was measured using an ultraviolet-visible-near-infrared spectrophotometer (Shimadzu UV-3101PC) combining with a square …

Zif-67-Derived Ag/Co-Embedded N-Enriched Mesoporous Carbon For Oxygen Reduction Reaction, Zheng-Ling Di, Jing Zhu, Lei Dai, Wei Meng, Yue-Hua Li, Zhang-Xing He, Ling Wang

Journal of Electrochemistry

Nitrogen-doped porous carbon materials are considered as one of the most promising catalysts for oxygen reduction reaction (ORR). Herein, in order to further improve the activity of the nitrogen-doped porous carbon, Ag/Co bimetal is embedded into nitrogendoped porous carbon to form Ag/Co-embedded nitrogen-doped porous carbon material (AgCo@NC). The AgCo@NC was derived by the wet impregnation of Ag+ into ZIF-67 precursor, followed by chemical reduction and a subsequent pyrolysis process under Ar atmosphere at different temperatures (500 ℃, 600 ℃, 700 ℃). The morphologic characterization shows that the Ag/Co nanoparticles were successfully embedded in the mesoporous carbon framework with abundant nitrogen …

Evaluation Of The Mechanisms And Effectiveness Of Nano-Hydroxides, Wood And Dairy Manure-Derived Biochars To Remove Fluoride And Heavy Metals From Water, Anna Rose Wallace, Wenjie Sun Dr, Chunming Su Dr

Civil and Environmental Engineering Theses and Dissertations

The development of effective treatment processes for the removal contaminants, such as fluoride and heavy metals, from polluted water have been urgently needed due to serious environmental health and safety concerns. In this dissertation, a variety of materials including various (hydro)oxide nanomaterials, biochars and surface modified biochar were studied to evaluate their effectiveness and mechanism on removing fluoride or mixed heavy metals from water.

In the Chapter 2, this study investigated the adsorptive removal of fluoride from water using various (hydro)oxide nanomaterials, focusing on ferrihydrite, hydroxyapatite (HAP) and brucite, which have the potential to be used as sorbents for surface …

Instrumentation For Dynamic Nuclear Polarization And Application Of Electron Decoupling For Electron Relaxation Measurement, Nicholas Howard Alaniva

Arts & Sciences Electronic Theses and Dissertations

Dynamic nuclear polarization nuclear magnetic resonance (DNP NMR) exploits internal electron spin and nuclear spin interactions to increase sensitivity and uncover valuable information regarding structure and dynamics of a system. To manipulate these interactions, instrumentation is developed to combine high-power microwave and radiofrequency irradiation with the ability to spin samples at the magic angle (MAS) at temperatures from 90 K to 4.2 K. Electron decoupling uses frequency-modulated microwaves to mitigate the electron-nuclear dipolar interaction, improving signal intensity and resolution in DNP NMR experiments. Electron decoupling is combined with short DNP periods to encode electron spin information in polarized nuclear signal. …

X-Ray Absorption Spectroscopy, X-Ray Diffraction And Optical Luminescence Studies Of Phase Transition Of Titania Nanotubes, Lu Yao

Electronic Thesis and Dissertation Repository

The one-dimensional (1D) TiO₂ nanotubes (NTs) and their derivatives have been extensively studied due to their wide applications, such as photocatalysts, solar cell, paints and so on. Since TiO₂ has a wide band gap (~3.0 eV), its photo-absorption as the photocatalyst only occurs in the UV region that wastes mostly solar energy. Therefore, the solution to higher photocatalytic efficiency has been sought for some time. This thesis presents a study of the size-dependent phase transitions of TiO₂ NTs using synchrotron-based X-ray techniques. The chemical environment including local symmetry and the luminescence origin of the TiO₂ NTs …

Nanopatterned Silk Fibroin Films With High Transparency And High Haze For Optical Applications, Corey Malinowski, Fengjie He, Yihong Zhao, Ivan Chang, David W. Hatchett, Shengjie Zhai, Hui Zhao

Chemistry and Biochemistry Faculty Research

Simultaneous high transparency and high haze are necessary for high-efficiency optical, photonic, and optoelectronic applications. However, a typical highly transparent film lacks high optical haze or vice versa. Here, we report a silk fibroin-based optical film that exhibits both ultrahigh optical transparency... (See article for full abstract).

Chemical Self-Assembly Strategies Toward The Design Of Molecular Electronic Circuits, Dustin Olson

Theses and Dissertations

The field of molecular electronics is generally divided into one of two major categories, the first focusing on the unique functionalization of single molecules to produce electronic behavior, the other utilizing large assemblies of molecules to produce electronic behavior. The former approach is largely attributed to the seminal paper by Aviram and Ratner in which they proposed a molecular donor-bridge-acceptor (D-B-A) type architecture could lead to single molecule rectification producing electronic effects similar to conventional semiconductor based diodes. Extensive research has been carried out in both fields as it is foreseen that new approaches to electronics miniaturization will be necessary …

Laser Spectroscopy Investigations Of Jet-Cooled Metal-Containing Free Radicals., Anam Chandra Paul

Electronic Theses and Dissertations

Metal-containing free radicals are important intermediates in metal-surface reactions and the interactions between metals and organic molecules. Among metal-containing free radicals, monovalent derivatives of alkaline earth metals have been extensively investigated by using spectroscopic techniques in a gas phase, mainly in Broida ovens or under supersonic-jet-cooled conditions. In the present study, the results of performed spectroscopic investigations of both metal-containing monoalkoxides (CaOR) and metal oxides (MO) radicals have been reported. Laser-induced fluorescence (LIF) and dispersed fluorescence (DF) spectra of the electronic transition of the calcium CaOR radicals have been obtained under jet-cooled conditions. Complete active space self-consistent field (CASSCF) and …

Laser Spectroscopy Investigations On Molecular And Free Radicals Dynamics., Hamzeh Telfah

Electronic Theses and Dissertations

Studying molecular dynamics and chemical kinetics is important to understand the chemical behavior of renewable energy sources. Laser spectroscopy techniques are powerful tools for the identification and diagnosis of such processes. In this dissertation, using our laser spectroscopy techniques, biofuels and solar energy were targeted as renewable energy sources study. We have studied the ultrafast exciton dynamics for a series of methylammonium lead bromide (CH3NH3PbBr3) nanostructures, nanocrystals (NCs, 0D), nanowires (NWs, 1D), and nanoplatelets (NPs, 2D) as a promising solar energy materials.1-2 Aided by analysis of UV−visible absorption and photoluminescence spectra, features in the transient absorption (TA) spectra are assigned …

Laser Spectroscopic Investigations Of Organic Alkoxy And Peroxy Radicals., Md Asmaul Reza

Electronic Theses and Dissertations

Understanding the mechanism of combustion reactions is key for advancing internal combustion engine design, improving the efficiency of ignition chemical reactions, and reducing pollutant formation. In order to model the extremely complicated chemical kinetics of combustion processes, it is critical to detect and identify transient reactive chemical intermediates, particularly free radicals. Hence, it needs to be fully understood the gas-phase chemistry of organic compounds in the lower atmosphere. Over the past fifty years, parallel advancement in observational, experimental, and theoretical techniques, tremendous strides have been made in our understanding of the role of organic compounds in the atmosphere. Combustion chemistry …

Understanding And Controlling Lithium Microstructure During Electroplating For Energy Applications, Yang Tian

Graduate Theses and Dissertations

Lithium-ion batteries are reaching the specific theoretical capacity limit, while lithium metal batteries are regarded as the ideal energy storage system for the next generation “beyond lithium-ion” battery systems. The lithium metal anode is considered as the “Holy grail” of anodes due to its relatively low electrochemical potential (-3.04 V vs SHE) and high theoretical capacity (3860 mAh g-1). However, the application of lithium metal anodes is hindered because of significant reaction between metallic lithium and electrolytes, as well as uneven electro-plating, which leads to dendrite formation, causing safety problems.

The kinetic parameters of Li ions such as diffusion coefficient …

Effects Of The Dihydrouracil Lesion On Dna Using 1h/31p 1d And 2d Solution Nmr, Benjamin M. Boyd

MSU Graduate Theses

The effects of the dihydrouracil lesion in DNA were studied using two dimensional NMR spectroscopy. The sequence used was based off of the Drew-Dickerson Dodecamer, with the cytosine in the three position replaced by a dihydrouracil. All of the nonexchangeable proton chemical shifts, with the exception of the H2, H5’, and H5’’, of the lesioned DNA were identified using NOESY spectra and then compared to the chemical shift values of the Drew Dickerson Dodecamer. The largest differences in chemical shifts were observed in the nucleotides neighboring the lesion, both within the strand and on the opposite strand. The imino exchangeable …

Galvanic Corrosion Of Copper-Coated Carbon Steel For Used Nuclear Fuel Containers, Thalia E. Standish

Electronic Thesis and Dissertation Repository

Carbon steel vessels coated with ∼3 mm of Cu have been proposed for the permanent disposal of used nuclear fuel in a deep geological repository (DGR) in Canada. In the event of an undetected defect in the Cu coating that exposes the steel substrate, galvanically accelerated corrosion of steel is, in principle, possible. To investigate this scenario, the progression of steel corrosion at the base of novel simulated through-coating defects was monitored electrochemically and imaged non-destructively using X-ray micro-computed tomography (micro-CT) as a function of time, O₂ availability (including anoxic conditions), and coating method (cold spray deposition (with and …

Saponin Penetration And Interactions With Membranes, Sarai Guerrero

Electronic Thesis and Dissertation Repository

The saponin QS21 has been used and studied for years as an adjuvant agent to improve vaccines for both humans and animals. However, how the saponin interacts with the membrane and itself remains poorly understood. We studied the QS21-A majority isomer using all-atom classical molecular dynamics simulations in model bilayers composed of cholesterol and either DOPC or DPPC. As this is one of the few computational studies on QS21-A, we had very few resources to compare our results to. Nevertheless, we were able to gain insight into possible configurations that QS21-A takes after penetration, the effect of the bilayer on …

Modeling And Simulations Of Peptoids, Pu Du

LSU Doctoral Dissertations

Polypeptoids, or poly-N-substituted glycines, are a class of sequence defined polymers that are structural mimics of polypeptides. Polypeptoids currently have received a growing interest due to their improved thermal stability, larger chemical diversity, and easier synthetic pathways as compared to peptides. Their lack of backbone hydrogen bonding and stereochemistry coupled with their easily tunability make them an ideal prototypical model system to study the effect of secondary/non-covalent interactions on self-assembly in solution. In order to develop a molecular level understanding of the effect of secondary interactions on polypeptoid self-assembly, systematic studies were carried out using molecular dynamics simulations on several …