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Full-Text Articles in Analytical Chemistry

Development Of A Digestion Procedure Using Fe2+ Ions For Electrochemical Detection Of Mno2 Particles In Drinking Water, Kayla Elliott, Sarah Jane Payne, Zhe She Nov 2025

Development Of A Digestion Procedure Using Fe2+ Ions For Electrochemical Detection Of Mno2 Particles In Drinking Water, Kayla Elliott, Sarah Jane Payne, Zhe She

Journal of Electrochemistry

Developing methods for detection contaminants in drinking water is essential to ensuring that safe and acceptable quality drinking water is delivered to consumers. While manganese (Mn) was previously known only as a mere aesthetic issue, recent epidemiological data has shown to have negative neurological effects on humans, especially on children, prompting new health-based guidelines by Health Canada and the World Health Organization. In drinking water, Mn exists predominantly as Mn(II) and Mn(IV), and is regulated based on total Mn levels. Interestingly, measurement of Mn particulate using electroanalytical methods has not yet been reported in the literature. Herein, a digestion procedure …


Electrochemical And Electrocatalytic Properties Of Screen-Printable Carbon Inks Featuring Pyridinic Nitrogen-Containing Polymeric Binder, Albert Sam Junior Aug 2025

Electrochemical And Electrocatalytic Properties Of Screen-Printable Carbon Inks Featuring Pyridinic Nitrogen-Containing Polymeric Binder, Albert Sam Junior

Electronic Theses and Dissertations

Screen-printable conductive inks have been widely applied to prepare electrodes for electrochemical sensing. These inks generally consist of conductive metal or carbon particles, solvents, and polymeric binders. Low-cost, carbon-based, screen-printable conductive inks are especially popular. However, screen-printed carbon electrodes (SPCEs) must often be modified after they are printed to impart the necessary characteristics (e.g., sensitivity, selectivity, stability) for the desired application. For example, nitrogen-doping of SPCEs, especially in ways that introduce pyridinic or pyrrolic nitrogen species, can impart electrocatalytic properties towards reduction of O2, H2O2, and CO2. While our previous work done …


Probing The Surface Structure Of Ferrocene Modified Electrodes Using Cyclic Voltammetry, Rebekah S. Stanley May 2024

Probing The Surface Structure Of Ferrocene Modified Electrodes Using Cyclic Voltammetry, Rebekah S. Stanley

Reviews, Analyses, and Instructional Studies in Electrochemistry (RAISE)

Modifying electrodes imparts new electrochemical properties for use in various applications. To fully understand these electrochemical properties the structure of the modified surface needs to be characterized. Cyclic voltammetry (CV) offers a quick and simple way to determine if the surface structure has been homogeneously modified even at low surface concentrations. Nonideal responses in CV scans give insights to the microenvironments and structure of the monolayer surface that may be indistinguishable in other techniques. Peak fitting CV data, coupled with other surface techniques, can further characterize the contributions and nature of these microenvironments and aid in structural determination.


Electrochemiluminescence Using Pencil Graphite Electrodes And Screen-Printed Carbon Electrodes Interfaced With A Simple Imaging System, Sandra Ehigiator May 2024

Electrochemiluminescence Using Pencil Graphite Electrodes And Screen-Printed Carbon Electrodes Interfaced With A Simple Imaging System, Sandra Ehigiator

Electronic Theses and Dissertations

Electrochemiluminescence (ECL) is a phenomenon whereby electrochemical reactions generate a product that is capable of emitting light. ECL’s high sensitivity, selectivity, extremely low background, and relatively simple instrumentation make it particularly well-suited for chemical sensing and biosensing strategies. Here we report a simple ECL imaging system based on a camera interfaced with a zoom lens to compare pencil graphite electrode (PGE) and screen-printed carbon electrode (SPCE) arrays as ECL platforms. With this system, ECL signals generated from tris(2,2′- bipyridine)ruthenium(II) chloride hexahydrate ([Ru(bpy)3]2+) using co-reactant tri-n-propylamine (TPA) were linear with respect to [Ru(bpy)3]2+ concentrations from 9 to 450 μM. Detection limits …


Nitro-Aromatic Polymers For Conversion-Style Battery Cathodic Materials, Brady P. Samuelson May 2022

Nitro-Aromatic Polymers For Conversion-Style Battery Cathodic Materials, Brady P. Samuelson

Honors Thesis

The development of organic electrode materials in rechargeable batteries has seen a resurgence in recent decades. This spike in interest is mostly due to the increased investments in renewable energy sources, grid-scale energy storage, and the rapid transition to electric vehicles. Current lithium battery cathode materials typically use some form of lithium metal oxide (specific capacity: 272 mAh g-1 which has problems with limited capacity, thermal runaway, and an unreliable supply chain. Our research group’s solution involves investigating new lightweight, organic redox groups combined with a conductive polymer backbone to serve as a possible replacement for the cathode in …


Transient Electrochemical Surface-Enhanced Raman Spectroscopic Study In Electrochemical Reduction Of P-Nitrothiophenol, Yun Ling, Jing Tang, Guo-Kun Liu, Cheng Zong Dec 2019

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 …


Synthesis Of Keggin Polyoxometalates Modified Carbon Paste Electrode As A Sensor For Dopamine Detection, Peng-Fei Dong, Na Li, Hai-Yan Zhao, Min Cui, Cong Zhang, Ju-Jie Ren, Xue-Ping Ji Oct 2018

Synthesis Of Keggin Polyoxometalates Modified Carbon Paste Electrode As A Sensor For Dopamine Detection, Peng-Fei Dong, Na Li, Hai-Yan Zhao, Min Cui, Cong Zhang, Ju-Jie Ren, Xue-Ping Ji

Journal of Electrochemistry

Polyoxometalates, a class of anionic clusters with structure diversity and size variability, make them very attractive in many fields such as electrochemistry, catalysis and medicine. The Co(C15N6H12)2[PW12O38]·5H2O(Co[PW12O38]) modified carbon paste electrode was prepared in this work, and its electrochemical performances as the sensor for dopamine detection were characterized with electrochemical impedance spectroscopy, cyclic voltammetry and differential pulse voltammetry. The preparation conditions and test conditions were optimized respectively. Under the optimized conditions, the POMs modified carbon paste electrode exhibited good selectivity and sensitivity …


Immobilization Of Gold Nanoparticles On Nitrided Carbon Fiber Ultramicroelectrodes By Direct Reduction, George Affadu-Danful Aug 2018

Immobilization Of Gold Nanoparticles On Nitrided Carbon Fiber Ultramicroelectrodes By Direct Reduction, George Affadu-Danful

Electronic Theses and Dissertations

Due to enhanced properties such as large surface area-to-volume ratio, metal nanoparticles are often employed as catalysts for various applications. However, most studies involving nanoparticle catalysts have been conducted on collections of particles rather than single nanoparticles. Results obtained for ensemble systems can be difficult to interpret due to variations in particle loading and interparticle distance, which are often challenging to control and characterize. In this study, two immobilization strategies for incorporating gold nanoparticles (AuNPs) on carbon fiber ultramicroelectrodes (UMEs) were compared with the goal of extending these techniques to nanoelectrodes for studies of single AuNPs. Both layer-by-layer deposition of …


Electrochemical Detection Of Ammonia In Aqueous Solution Using Fluorescamine: A Comparison Of Fluorometric Versus Voltammetric Analysis, Panchompoo Janjira, G. Compton Richard Oct 2012

Electrochemical Detection Of Ammonia In Aqueous Solution Using Fluorescamine: A Comparison Of Fluorometric Versus Voltammetric Analysis, Panchompoo Janjira, G. Compton Richard

Journal of Electrochemistry

Fluorescamine is a non-fluorescent reagent widely used for the quantitative determination of primary amines by fluorescence spectroscopy as it reacts readily with primary amines to form a fluorescent product. In this work, a new sensitive voltammetric method for the detection of ammonia in aqueous solution by the reaction with fluorescamine has been developed. First, the electrochemical behaviour of fluorescamine in the absence and presence of ammonia was investigated in 0.1 mol L-1 borate buffer solution (pH 9.0) by cyclic voltammetry using a glassy carbon (GC) electrode. As for fluorescamine itself, a well-defined irreversible oxidation peak could be observed at …


Electrochemical Behavior Of Imidacloprid, Jie-Qiong Wang, Wang Zhang, Ming Chen, Guo-Wang Diao Feb 2012

Electrochemical Behavior Of Imidacloprid, Jie-Qiong Wang, Wang Zhang, Ming Chen, Guo-Wang Diao

Journal of Electrochemistry

The electrochemical behavior of imidacloprid(IDP)on glassy carbon electrode has been investigated by cyclic voltammetry. The result shows that the electrochemical reduction of IDP is irreversible and controlled by diffusion. At 25 ℃, the numbers of the electrons transferred of IDP in the electrochemical reaction are four. The diffusion coefficient of IDP is 2.44×106 cm2·s-1 and the diffusion activation energy is calculated to be 9.33 kJ·mol-1.


Electrochemistry Of Pani/Metal Composites In Basic Solutions, Tamthinhan Quy Dec 2011

Electrochemistry Of Pani/Metal Composites In Basic Solutions, Tamthinhan Quy

UNLV Theses, Dissertations, Professional Papers, and Capstones

Polyaniline (PANI) has been extensively investigated due to its unique conductivity, which is primarily dependent on the oxidation state of the material and the solution pH. PANI is an insulator when it is oxidized, and the solution pH exceeds four. Numerous attempts to extend PANI's conductivity to neutral and alkaline environments have been unsuccessful. However, our previous study has demonstrated that PANI/Pd composite is conductive and catalytically active in a basic solution, pH ∼ 12. Therefore, the conductivity and the electrochemical properties of PANI composites including PANI/Au, PANI/Pd and PANI/Pt were evaluated in basic solutions. The fundamental studies of PANI/metal …


Determinations In Reducing Degree Of Iron-Amine Complex By Cyclic Voltammetry, Yu-Kun Lai, Wei Wang Feb 2011

Determinations In Reducing Degree Of Iron-Amine Complex By Cyclic Voltammetry, Yu-Kun Lai, Wei Wang

Journal of Electrochemistry

The veracity and influence factors in reducing degree on iron-amine complex were tested by cyclic voltammetry.The types of cathode electrolytes including ferric nitrate,triethanolamine,sodium hydroxide and calcium nitrate were optimized.Compared with dip-dyeing coloration method,the cyclic voltammetry method can be used to measure the reducing degree of iron-amine complex more accurately with better stability,easier and faster operation.Potential applications of cyclic voltammetric determination method can be found in the fields of electrochemical dye production and related quality control.


Electrochemical Studies Of Quinone On Clay-Modified Platinum Electrodes, Thomas Edward Nelson Jan 2011

Electrochemical Studies Of Quinone On Clay-Modified Platinum Electrodes, Thomas Edward Nelson

Theses (2 year embargo)

No abstract provided.


Cyclic Voltammetric And In-Situ Ftir Spectroscopic Studies Of Adsorption And Reduction Of No On Electrode Of Pt Nanoparticles, Qian Cheng, Yan-Xia Jiang, Dong-Mei Zeng, Shi-Gang Sun Nov 2009

Cyclic Voltammetric And In-Situ Ftir Spectroscopic Studies Of Adsorption And Reduction Of No On Electrode Of Pt Nanoparticles, Qian Cheng, Yan-Xia Jiang, Dong-Mei Zeng, Shi-Gang Sun

Journal of Electrochemistry

Adsorption and reduction of NO on electrode of Pt nanoparticles in acid solutions were studied by means of cyclic voltammetry(CV) and in-situ FTIR spectroscopy.The results indicated that the reduction of NO is a complicated process including the adsorption of NO on electrode surface.Two types of surface-bonded NO were determined on Pt nanoparticles.The weakly adsorbed NO was reduced between 0.6 V and-0.05 V,which yielded nitrous oxide(N2O) and ammonium(NH4+) as products;while the strongly bonded NO was reduced at more negative potentials between-0.05V and-0.15V,producing only NH4+ species.


Surface-Enhanced Raman Spectra Of Cytosine Adsorbed On A Roughened Gold Electrode, Yuan-Fei Wu, Jian-Feng Li, De-Yin Wu, Bin Ren, Zhong-Qun Tian Aug 2005

Surface-Enhanced Raman Spectra Of Cytosine Adsorbed On A Roughened Gold Electrode, Yuan-Fei Wu, Jian-Feng Li, De-Yin Wu, Bin Ren, Zhong-Qun Tian

Journal of Electrochemistry

Cytosine adsorbed on a roughened gold electrode has been investigated by using electrochemical cyclic voltammetry and surface-enhanced Raman spectroscopy (SERS). The results indicate that cytosine was adsorbed on the Au electrode in a perpendicular orientation via the N3 position. As the maximum enhancement of ring breathing mode appears at negative potentials compared with other modes, both the electromagnetic enhancement and the charge transfer mechanism were considered to contribute to the SERS intensity. The binding interaction between cytosine and the gold electrode was weakened when the potential was negatively moved. The result also indicates that the SERS technique can be used …


Study Of The Effect Of Rare Earth Ions On Dna Using Cyclic Voltammetry And Spectroscopy, Hei-Bai Shen, Yu-Zhuan Kang, Hai-Feng Yang, Lin Yu, Zong-Rang Zhang Nov 1998

Study Of The Effect Of Rare Earth Ions On Dna Using Cyclic Voltammetry And Spectroscopy, Hei-Bai Shen, Yu-Zhuan Kang, Hai-Feng Yang, Lin Yu, Zong-Rang Zhang

Journal of Electrochemistry

The interaction between rare earth ions(e.g. Eu3+ ,Ce3+, Er3+, Sm3+, Tb3+, La3+ and Nd3+) and DNA had been investigated by using Cyclic Voltammetry, Ultraviolet and Raman Spectroscopy. After the adding of Ce3+ ion to DNA solution, the cathodic peak current of Ce3+ ion reduction was found to decrease obviously, and the anodic peak current to decrease even more significantly. Differential UV spectra of Ce3+ ion depicted hyperchromic effect after the reaction of these two species and a new peak of 272 nm was found. Differential …


Ohmic Drop Compensation In Voltammetry:  Iterative Correction Of The Applied Potential, David O. Wipf Jan 1996

Ohmic Drop Compensation In Voltammetry:  Iterative Correction Of The Applied Potential, David O. Wipf

CAS Publications

A new method of ohmic potential drop correction for use with potential step and sweep voltammetric methods is described. The method, iterative correction of the applied potential (ICAP), essentially replaces an electronic positive feedback correction with a digital positive feedback correction. This paper will present one form of the ICAP procedure, in which voltammetric current data acquired by a high-speed digital oscilloscope are used to iteratively generate a compensating potential waveform that is then synthesized by an arbitrary waveform generator. The ICAP method is advantageous for high-speed measurements, since many of the difficulties caused by electronic positive feedback compensation are …