Physical Sciences and Mathematics Commons^™

Copper Nanoparticles In-Situ Anchored On Nitrogen-Doped Carbon For High-Efficiency Oxygen Reduction Reaction Electrocatalyst, Hui-Fang Yuan, Yue Zhang, Xing-Wu Zhai, Li-Bing Hu, Gui-Xian Ge, Gang Wang, Feng Yu, Bin Dai

Journal of Electrochemistry

Compared with noble metal platinum (Pt)-based catalysts, inexpensive non-noble metal electrocatalysts have attracted extensive attention for oxygen reduction reaction (ORR). Herein, chitosan as a kind of biomass resource rich in nitrogen and carbon was used to prepare nitrogen-doped carbon (N-C) and N-C in-situ anchored by copper nanoparticles (Cu/N-C). The as-obtained N-C and Cu/N-C nanoparticles were successfully used as non-noble eletrocatalysts tested for ORR. Compared with the N-C, the Cu/N-C showed the high surface area of 607.3 m 2·g-1 with the mean pore size of 2.5 nm and the pore volume of 0.40 cm3·g-1. The most positive Gibbs free …

Effect Of Glycol Based Coolant Pollution On Pem Fuel Cells Stack And Recovery Measures, Cong-Yi Zhu, Xiao-Hui Li, Quan-Quan Gan

Journal of Electrochemistry

As the heat conduction medium of fuel cell cooling system, coolant is very important for the thermal management of fuel cell stack. In practical application, coolant leakage into the stack often occurs. Due to the randomness of fault location of components, the location of coolant leakage is uncertain, which may occur on the cathode side or anode side of some or all single cells. The main effects of coolant pollution on fuel cell stack are as follows: the output of open circuit voltage decreases sharply, the consistency of single cells voltage decreases and so on, which seriously affects the normal …

Functional Sulfate Electrolytes Enable The Enhanced Cycling Stability Of Nati2(Po4)3/C Anode Material For Aqueous Sodium-Ion Batteries, Shu-Jin Li, Zhi-Kang Cao, Wen-Kai Wang, Xiao-Han Zhang, Xing-De Xiang

Journal of Electrochemistry

Aqueous sodium-ion batteries show promising application in fields of large-scale storage of intermittent renewable energies owing to the earth-abundant sodium resources and incombustible aqueous electrolytes. Primary factors determining whether they can be commercially utilized are low cost and long lifetime. Among current electrode materials, NASICON-type NaTi₂(PO₄)₃ arouses wide interests as an anode material for aqueous sodium-ion batteries as it offers a high specific capacity, fast Na-transport ability and reasonable working potential, however, suffering from insufficient cycling performance caused by severe dissolution of active materials in traditional aqueous electrolytes. In this work, a functional sulfate electrolyte …

Nitrogen-Sulfur Co-Doped Porous Carbon Preparation And Its Application In Lithium-Sulfur Batteries, Zhao Gui-Xiang, Hafiz Zaki Ahmed Wail, Zhu Fu-Liang

Journal of Electrochemistry

In recent years, lithium-sulfur (Li-S) batteries have been considered as a promising candidate for the next generation of energy storage system due to their ultrahigh theoretical capacity (1675 mAh·g-1) and energy density (2600 Wh·kg-1). However, the practical application of Li-S batteries is seriously limited by their insulating nature of sulfur, the shuttle effect of polysulfides (LiPSs), and volume expansion during charging and discharging. To overcome those disadvantages, one of the commonly methods is to infiltrate sulfur into porous conductive carbon framework, such as porous carbon, hollow carbon spheres, graphene, carbon nanotubes and some composites of the above structures to achieve …

Cyclic Voltammetric Simulations On Batteries With Porous Electrodes, Xue-Fan Cai, Sheng Sun

Journal of Electrochemistry

Lithium-ion batteries (LIBs) are among the most widely used energy storage devices. Whole-cell modeling and simulations of LIBs can optimize the design of batteries with lower costs and higher speeds. The Pseudo-Two-Dimensional (P2D) electrochemical model is among the most famous whole-cell models and widely applied in LIB simulations. P2D model consists of a series of kinetic equations to model Li+/Li diffusion in working/counter electrodes and electrolytes, which are filled in the porous electrodes and separator, and reactions at the interface of electrolyte and active particles. The traditional applications of P2D model, however, are limited to the cases where the current …

Effect Of Aluminum Alloy Surface Modification On Adhesion Of The Modified Polyurethane Coating And Its Corrosion Protective Performance, Xian-Yin Kuang, Shao-Qiang Jin, Yan-Hui Cao, Yan-Mei Zhang, Shi-Gang Dong, Long-Hui Zhu, Li-Wen Lin, Chang-Jian Lin

Journal of Electrochemistry

The ordinary organic coatings on aluminum alloy usually encounter a problem of low adhesion to the substrate, which results in destruction and failure of the long-term protective performance of the anticorrosion systems. The surface modification of aluminum alloy is able to enhance the adhesion of organic coating on aluminum alloys, and to improve their protective performance. In this work, a combined surface modification of anodic oxidation and mussel adhesion protein/CeO₂/3-aminopropyltriethoxysilane composite film (MCA) was developed on the aluminum alloy. The adhesion of modified polyurethane coated on the treated aluminum alloy and its corrosion protective performance were evaluated comprehensively …

Photoelectrochemical Sensing Based On Zr-Mofs For Homocysteine Detection, Wen-Xia Dong, Guang-Ming Wen, Bin Liu, Zhong-Ping Li

Journal of Electrochemistry

Due to the independent form of the light source and detection system, photoelectrochemical (PEC) sensor has the advantages of low background, high sensitivity and simple operation. So far, PEC systems have been widely used in the fields including the actual detection of metal ions, biological antibodies or antigens in environmental pollutants. When the photosensitive material is irradiated by a light source with an energy being equal to or greater than its band gap, electrons (e-) transition occurs from the valence band to the conduction band, leaving a hole (h+), at the same time, the generated electron-hole pair (e-/h+) separate, and …

Structure Analysis Of Pemfc Cathode Catalyst Layer, Rui-Qing Wang, Sheng Sui

Journal of Electrochemistry

The sluggish oxygen reduction reaction (ORR) on the cathode of the proton exchange membrane fuel cell (PEMFC) has always been one of the key factors limiting its commercialization. The optimization of the cathode catalytic layer structure plays an important role in improving fuel cell performance and reducing production costs. In this paper, two different catalysts (platinum nanoparticles (Pt-NPs) and platinum nanowires (Pt-NWs)) were prepared by using catalyst coated substrate (CCS) method. By constructing a double-layer catalytic layer structure, we analyzed the effect of different catalytic layer structures by performing a single cell test. The results showed that the dense platinum …

Formation And Morphological Evolution Of Nanoporous Anodized Iron Oxide Films, Jin-Wei Cao, Nan Gao, Zhao-Qing Gao, Chen Wang, Sheng-Yan Shang, Yun-Peng Wang, Hai-Tao Ma

Journal of Electrochemistry

The preparation of iron oxide films with nanoporous structure by anodization has attracted much attention for its potential applications. However, the formation mechanism of porous structure during anodization is still unclear. In this paper, the composition of anodic current during the formation of nanoporous anodized iron oxide film was analyzed in combination with the current density-potential response (I-V curve) and the derivation of Faraday’s law. The results showed that the anodic current consisted of an ionic current (leading to the migration of ions to form oxide) and an electronic current (leading to the oxygen evolution), and the …

Influence Of Heat Treatment Time On Cathode Material Cr8O21 For Lithium Battery, Jiu-Kang Teng, Qing-Jie Wang, Liang Zhang, Hong-Mei Zhang, Xiao-Tao Chen, Peng Zhang, Jin-Bao Zhao

Journal of Electrochemistry

Chromium oxide (Cr₈O₂₁) cathode material for lithium batteries was synthesized by thermal decomposition of chromium trioxide (CrO₃) at high temperature. The electrochemical properties of chromium oxide depended on the time and temperature during the heat treatment. Pure phase chromium oxide was prepared, and the effects of heat treatment time on the structures and electrochemical properties of Cr₈O₂₁ were systematically studied. The first discharge mechanism of chromium oxide in lithium batteries was explored, and the results were similar to that in lithium-sulfur batteries. The crystal phases and electrochemical properties of the prepared …

The Immobilization Of Ticagrelor On Implant Materials And Corrosion And Biofouling Inhibition By Novel Layered Polymer Thin Films For Marine Application, Tell Lovelace

Electronic Theses and Dissertations

Percutaneous coronary interventions are a widely used cardiovascular surgery which is typically accompanied by the insertion of a vascular stent. After the procedure patients are put on dual anti-platelet therapy (DAPT) to prevent stent thrombosis, a common complication to this procedure in which platelets aggregate in the blood vessel on the inserted stent. Systemic deactivation of platelets in patients via oral DAPT results in patients becoming bleeding risks in future medical procedures, necessitating the development of a localized delivery system for anti-platelet medications from the surface of the stent. A novel anti-thrombogenic vascular stent coating has been prepared by covalent …

Ultrasound-Driven Fabrication Of Nanosized High-Entropy Materials For Heterogeneous Catalysis, Francis Uchenna Okejiri

Doctoral Dissertations

High-entropy materials (HEMs) have emerged as a new class of multi-principal-element materials with great technological prospects. As a unique class of concentrated solid-solution materials, HEMs, formed on the premise of incorporating five or more principal elements into a single crystalline phase, provide an excellent opportunity to access superior catalytic materials ‘hiding’ in the unexplored central regions of a multicomponent phase space of higher orders.

However, the fabrication of HEMs is energy-intensive, typically requiring extreme temperatures and/or pressures under which agglomeration of particles occurs with a commensurate decrease in surface area. For most catalytic applications, non-agglomerated particles with high surface areas …

A Tribute To Professor Gaetano Granozzi And His Contributions To Surface Science On The Occasion Of His 70th Birthday, Kurt W. Kolasinski

Chemistry Faculty Publications

On the occasion of his 70th birthday, we celebrate the career of our Editor-in-Chief, Professor Gaetano Granozzi. Prof. Granozzi’s work is marked by his dedication to the fundamental understanding of technologically relevant systems through the lens of surface science.

Exploring The Potential Of Ionothermal Syntheses For High-Performance Lithium-Ion Battery Anode Materials, Runming Tao

Doctoral Dissertations

Renewable energy storage systems are regarded as the solution to the environmental and energy crises caused by the burning of fossil fuels in vehicles. Unfortunately, owning to the limits to the electrochemical performance of the current anode materials, lithium-ion batteries [LIBs] are still lacking strength in the charging rate-capability and thereby cannot fulfill future application requirements in electrical vehicles [EVs].

Particularly, graphite with a high theoretical specific capacity of 372 mAh/g is unsuitable for EVs due to the safety concerns of passivating solid-electrolyte interphase [SEI] resulted from the low operation potential of 0.1 V versus Li/Li⁺. The other …

Synthesis And Characterization Of 4,6-Protected Glucosamine Derivatives And Branched Glycoconjugates, Jonathan Bietsch

Chemistry & Biochemistry Theses & Dissertations

Low molecular weight gelators (LMWGs) are small molecules that self-assemble in appropriate solvents to form three dimensional networks that immobilize the solvent, creating a supramolecular gel. The self-assembly of LMWGs occurs through non-covalent interactions such as hydrogen bonding, aromatic interactions, donor-acceptor interactions, Van der Waals interactions, hydrophobic forces, halogen bonding, etc. Due to self-assembly occurring through reversible non-covalent interactions, supramolecular gels can undergo a gel to solution transformation. Because of this, these materials can be sensitive to external stimuli such as temperature changes, pH changes, and other stimuli that effect non-covalent interactions. This makes the synthesis of LMWG’s an appealing …

Synthesis And Characterization Of Pyridine-Based Diimide Ligands And Metal Phosphonate Coordination Polymers, Juan Pinedo

Honors Program Theses and Research Projects

Coordination polymers have been a topic of interest because of the large variety of applications these materials have. in particular Metal-Organic Frameworks (MOFs) have been researched due to their porosity and simple synthetic pathways. Structurally a MOF is composed of one or more organic ligands serving as the backbone of the structure. These ligands are complexed with metal ions coordinating into the desired structure. It is this structure that gives way to a variable porosity useful for proton conductivity and material transport. By varying backbone size a framework can be customized for use in specific conditions. This is due not …

Investigating Thermodynamics And Kinetics Of Methylene Blue And Eriochrome Black-T Adsorption On Activated Carbon Prepared From Coconut Husk, Abdul Rahman Wahoud, Lotfi Abdul Samed Bawazer

Hadhramout University Journal of Natural & Applied Sciences

In this research, the adsorption process was studied for methylene blue eriochrome black-T from aqueous solutions on the surface of activated carbon prepared from coconut husk by chemical activation with potassium hydroxide. The results show that the adsorption isotherm for methylene blue follows the Langmuir model while it follows the Freundlich model and the maximum adsorption capacity was 909 mg/g for methylene blue and 262 mg/g for eriochrome black-T. The equilibrium contact time reached in about 90 minutes at lower concentrations and 120 minutes at higher concentrations. Two simplified kinetic models including pseudo-first-order and pseudo-second-order equations were selected to follow …

Performance And Mechanism Of PtXCuY/C Electrocatalyst For Methanol Oxidation, Jia Tang, Xiao-Ming Zhang, Shan-Sheng Yu, Su-Li Wang, Gong-Quan Sun

Journal of Electrochemistry

Direct methanol fuel cell (DMFC), which directly converts the chemical energy of methanol fuel into electrical energy, has the advantages of high energy conversion efficiency, environmental friendliness, and abundance of fuel sources. DMFC is considered as the promising substitutes in the field of portable devices, military applications, and stationary power stations, while the broad application is severely hindered by the sluggish kinetic of methanol oxidation reaction (MOR) in the anode and the high cost of platinum (Pt)-based anodic electrocatalysts. Herein, a series of carbon supported Pt_xCu_y (Pt_xCu_y/C) binary metal electrocatalysts, featured with high …

Synthesis Of Nickel Phosphide/Nitrogen Phosphorus Co-Doped Carbon And Its Application In Lithium Ion Batteries, Jian Hu, Yan-Shuang Meng, Qian-Ru Hu

Journal of Electrochemistry

In recent years, the nickel-based phosphide has drawn great attention because of its low intercalation/deintercalation platform and lower polarization compared to sulfides and oxides as anodes for next-generation high-energy lithium-ion batteries. The Ni₂P anode can deliver high theoretical specific capacity of 542 mAh·g-1, but it subject to a conversion reaction mechanism, which make them unsuitable for commercial applications. The agglomeration of Ni₂P nanoparticles during material fabrication and the structural deterioration of electrode associated with large volume change during charge-discharge process lead to poor cycle stability and low utilization of active materials. Meanwhile, the low intrinsic conductivity …

Effect Of Alkyl Chain Length Of Symmetrical Quaternary Ammonium Hydroxide On Oxalic Acid Electroreduction Reaction, Bo Huang, Xin-Sheng Zhang, Dong-Fang Niu, Shuo-Zhen Hu

Journal of Electrochemistry

Glyoxylic acid with the dual characteristics of acid and aldehyde is an important chemical raw material and organic synthesis intermediate, which is extensively used in the perfumery, pharmaceutical and fine chemical industries. A family of symmetric quaternary ammonium hydroxides (QAHs) with different alkyl chain lengths was used as the additives in generating glyoxylic acid from oxalic acid electroreduction reaction (OAER). The effects of alkyl chain length on OAER and the corresponding side reaction, i.e., hydrogen evolution reaction (HER), were investigated. Linear sweep voltammetric (LSV) results showed that the adsorption of the additives suppressed more on the HER than that on …

Preparation Of Modified Titanium Based Pbo2 Electrode And Its Rapid Detection Of Cod, Qi Sun, Yan-He Han, Xiao-Lu Fu

Journal of Electrochemistry

In the traditional Ti/β-PbO₂ electrode, the crystal lattice difference between β-PbO₂ and Ti matrix is large, and the prepared electrode is easy to fall off and has a short service life. It needs to be modified in actual use. Based on the advantages of α-PbO₂ material and Ag material in terms of adhesion and conductivity, respectively, the above two materials are selected as the intermediate layer of Ti/β-PbO₂ electrode to improve electrode performance. In this paper, by preparing Ti/α/β-PbO₂ and Ti/Ag/β-PbO₂ electrodes …

Application Of Ti/Ruo2-Iro2-Sno2-Sb2O5 Anode In Rural Drinking Water Disinfection, Jing-Ru Guo, Xue-Jiao Zhang, Shuai Liao, Xue-Ming Chen

Journal of Electrochemistry

Sodium hypochlorite disinfection has many advantages, including reliable operation, low cost, easily available raw materials. It is, therefore, suitable for disinfection of drinking water in remote rural areas. The service life and chlorine evolution efficiency of the anode are the main factors restricting the performance of the sodium hypochlorite generator. The special conditions of frequent shutdown and low electrolyte concentration in the rural drinking water application also put forward high requirements on the performance of the anode. In this study, Ti/RuO₂-IrO₂-SnO₂-Sb₂O₅,a new-type and efficient chlorine evolution anode, was prepared by …

Electrochemical Synthesis Of P-(Β-Hydroxyethyl Sulfone) Aniline, Hao Guo, Dong-Fang Niu, Shuo-Zhen Hu, Xin-Sheng Zhang

Journal of Electrochemistry

Para-ester is the most important intermediate for the preparation of ethylene sulfone type reactive dyes, which is usually used in the dyeing of cellulose fibers and synthetic fibers. P-(β-hydroxyethyl sulfone) aniline is an important intermediate for the synthesis of para-ester. In this paper, p-(β-hydroxyethyl sulfone) aniline was prepared by electrochemical method, having the advantages of simple process, mild reaction condition, less environmental pollution, easy reaction control and so on. It has strong development potential and industrial application prospect. The electrochemical reduction of p-nitrophenyl-β-hydroxyethyl sulfone on a lead plate electrode to prepare p-(β-hydroxyethyl …

Mathematical Expression And Quantitative Analysis Of Impedance Spectrum On The Interface Of Glassy Carbon Electrode, Lei Cheng, Pu-Xuan Yan, You-Jun Fan, Hua-Hong Zou, Hong Liang

Journal of Electrochemistry

Glassy carbon electrode (GCE) is a common basic electrode for various electrochemical sensors, and the detection properties are determined by its interfacial characteristics. In this paper, we established an equivalent circuit including electrolyte resistance (R_el), charge transport resistance (R_ct), diffusion impedance (R_di, C_di), electrochemical (oxidation/reduction) reaction impedance (R_R, C_R), surface adsorption impedance (R_ads , C_ads), double-layer capacitance (C_DL), and derived the mathematical expression for the equivalent circuit. The R_el and C_DL are contributed by inactive …

Fundamentals Of Electrochemical Impedance Spectroscopy For Macrohomogeneous Porous Electrodes, Xiang Li, Qiu-An Huang, Wei-Heng Li, Yu-Xuan Bai, Jia Wang, Yang Liu, Yu-Feng Zhao, Juan Wang, Jiu-Jun Zhang

Journal of Electrochemistry

Electrochemical impedance spectroscopy (EIS) can be used to diagnose charge transfer reactions and mass transport in porous electrodes. The charge transfer reactions include interfacial charge accumulation and charge conduction as well as electrochemical reaction. In this paper, the complex phasor method is developed under the macrohomogeneous assumption to build an impedance model of porous electrodes for clarifying several vague expressions in the traditional approaches. The following researches are carried out: (1) Identifying characteristic parameters for the porous electrodes, including electrode electronic conductivity σ₁, electrolyte ionic conductivity σ₂, interface charge transfer conductivity g_ct, unit area …

Janus-Tinbco2 For Hydrogen Evolution Reaction With High Conductivity And Catalytic Activity, Li-Li Xu, Dong-Yan Ren, Xiao-Feng Zhao, Yong Yi

Journal of Electrochemistry

Exploring the potential hydrogen evolution reaction (HER) catalysts with the high activity and high conductivity has always been a hot spot in the research of renewable energy development. Ti₂C, as one of the 2D-MXene, has excellent properties relating to many active sites, mechanical stability, conductivity, etc., and has become a potential HER catalyst. However, the modification of the surface of Ti₂C by terminal O will reduce the conductivity, thereby limiting the transport of electrons between the valence band and the conduction band. In this study, an electric double layer Janus-TiNbCO₂ was constructed by Nb doping. …

Structural Tuning And Spectroscopic Characterizations Of Polysulfide As Battery Materials, Daiqiang Liu

Electronic Thesis and Dissertation Repository

Polysulfide materials have drawn extensive attention for next-generation battery development since the current lithium-ion battery has almost reached its limit regarding energy density and safety issues. Many phosphorus and sodium sulfide materials have been used in different battery types, such as solid-state and sodium-sulfur batteries. However, there are still issues that prevent these techniques from applications. In recent years, there has been increasing attention on investigations of the structural and phase transformations of electrode and electrolyte materials under high pressure. Many studies have shown that external pressure can affect structural properties and influence electrical properties. In this study, three battery-related …

National Chemistry Week: From Irl To The Web, Ilayda Kelley, Daniela Mesa Sanchez

Purdue Journal of Service-Learning and International Engagement

National Chemistry Week, an outreach program initiated by the American Chemical Society (ACS), encourages scientists to bring their love of chemistry to their community. Celebrated nationwide, ACS invites businesses, schools, and individuals to organize and participate in community events to promote the value of chemistry in everyday life. The Purdue graduate student chapter of Iota Sigma Pi, a national honor society for women in chemistry, annually organizes one such celebration. On a normal year, this event is a large logistical undertaking in which 100+ volunteers go directly to over 70 local elementary school classrooms and perform a series of activities …

Developing Covalent-Organic Frameworks For Protecting Against Radiation, Megan J. Francis

Senior Theses

This research focuses on the development of lightweight, thermostable dual-function materials for secondary radiation protection and sensing by the integration of hydrogen-rich aliphatic chains inside the porous matrix of covalent-organic frameworks (COFs). The main aims of this project are the synthesis of organic linkers for forming a robust porous COF, synthesizing the porous COF through a condensation reaction, the development of hydrogen-rich aliphatic chains, and integration of aliphatic chains into COFs through click chemistry. This manuscript outlines the methodology and development of a novel self-assembled crystalline, porous material engineered to combine the functions of a shield and sensitive dosimeter. The …

Hemoglobin-Modified Core–Shell Fe3o4@Au Nanostructures For The Electrochemical Detection Of Acrylamide, Endang Saepudin, Tri Yuliani, Mochammad Arfin Fardiansyah Nasution, Munawar Khalil, Jong Wook Hong, Tribidasari Anggraningrum Ivandini

Makara Journal of Science

In this study, electrochemical detection of acrylamide using hemoglobin (Hb)-modified core–shell Fe₃O₄@Au nanostructures was conducted. Fe₃O₄ nanoparticles (~4.9 nm) and core–shell Fe₃O₄@Au (5.0–6.4 nm) nanostructures were successfully synthesized by the thermal decomposition method. Electrochemical investigation revealed that the optimum amount of Hb of 2 mg/mL could be immobilized in 0.1 M acetate buffer solution (pH = 6). Moreover, the detection of acrylamide using Fe₃O₄@Au/Hb was evaluated by the cyclic voltammetry technique. A linear calibration curve (R² = 0.98) in the concentration range of …