Soft Ion Sputtering Of Pani Studied By Xps, Afm, Tof-Sims, And Sts,
2020
Stockholm University
Soft Ion Sputtering Of Pani Studied By Xps, Afm, Tof-Sims, And Sts, Christopher M. Goodwin, Zachary E. Voras, Xiao Tong, Thomas P. Beebe, Jr.
Chemistry Faculty Publications
Herein is a study of the soft sputtering method, gas cluster ion sputtering (GCIS), and its effects on the atomic, morphologic, and band structure properties of polyaniline (PAni) as studied with X-ray photoelectron spectroscopy (XPS), time-of-flight secondary ion mass spectrometry, atomic force microscopy, and scanning tunneling spectroscopy (STS). The GCIS source used was a 1000 argon atom cluster with 4 keV energy, which resulted in a sputter yield of 3.4 ± 0.2 × 10−3 nm3 per argon atom. Soft ion sputtering reduced the sample by explicitly removing the oxidized contaminants as determined by surface sensitive techniques: XPS and Time-of-flight secondary …
Water-Soluble Graphene In Agar Gel As Electrolyte For Magnesium-Air Battery,
2020
Universiti Malaya
Water-Soluble Graphene In Agar Gel As Electrolyte For Magnesium-Air Battery, Liew Siaw Ying
Student Works (2020-2029)
Presently, ever-increasing demands on energy and the global environmental issues have given the impetus to investigate the new battery systems which are inexpensive, efficient, having high performance, and also green to the environment. Among all the battery technologies, magnesium-air (Mg-air) battery is an attractive battery to be developed owing to the interesting properties of the Mg anode. Mg has high specific energy (6.46 kWh kg-1) and reactivity, apart from its high abundance, lower cost, low toxicity, and comparatively safe to handle in the atmosphere. Nevertheless, Mg-air battery is still not being widely investigated as compared to the other batteries. Electrolyte …
Low-Load Metal-Assisted Catalytic Etching Produces Scalable Porosity In Si Powders,
2020
University of Eastern Finland
Low-Load Metal-Assisted Catalytic Etching Produces Scalable Porosity In Si Powders, Konstantin Tamarov, Riku Kiviluoto, Josph D. Swanson, Bret A. Unger, Alexis T. Ernst, Mark Aindow, Joakim Riikonen, Vesa-Pekka Lehto, Kurt W. Kolasinski
Chemistry Faculty Publications
The recently discovered low-load metal-assisted catalytic etching (LL-MACE) creates nanostructured Si with controllable and variable characteristics that distinguish this technique from the conventional high-load variant. LL-MACE employs 150 times less metal catalyst and produces porous Si instead of Si nanowires. In this work, we demonstrate that some of the features of LL-MACE cannot be explained by the present understanding of MACE. With mechanistic insight derived from extensive experimentation, it is demonstrated that (1) the method allows the use of not only Ag, Pd, Pt, and Au as metal catalysts but also Cu and (2) judicious combinations of process parameters such …
Hexacyanoferrate-Based Nanocomposites For The Electrochemical Sensing Of Hydrogen Peroxide And Nicotine,
2020
Universiti Malaya
Hexacyanoferrate-Based Nanocomposites For The Electrochemical Sensing Of Hydrogen Peroxide And Nicotine, Lee Pui Kee
Student Works (2020-2029)
Metal hexacyanoferrate (MeHCF) is a unique material that not only acquired immense research interest in electrochemical sensing field but also possesses potential as energy storage material. As such, the present thesis sought to investigate the facile method to synthesis MeHCF-based nanocomposites and explore its possible applications. First, comparative research on the synthesis of Prussian blue-polypyrrole (PB-PPy) nanocomposite by novel self-assembly (SA) method and conventional electrodeposition technique was performed. PB-PPy nanocomposites were prepared by the novel self-assembly method and via the electrodeposition approach. The nanocomposites were compared in term of surface morphology and its electrochemical and electrocatalytic characteristics. The results indicated …
Synthesis And Characterization Of Water-Soluble Polyaniline For Hydrazine Detection / Hazira Hussin,
2020
Universiti Malaya
Synthesis And Characterization Of Water-Soluble Polyaniline For Hydrazine Detection / Hazira Hussin, Hazira Hussin
Student Works (2020-2029)
In this study, polyaniline (PAni) was synthesized through the chemical oxidation method using aniline (Ani) as a monomer, hydrochloric acid (HCl) as a dopant, and ammonium persulphate (APS) as an initiator. PAni was rendered water soluble through treating with cellulose derivatives. Cellulose derivatives such as methylcellulose (MC), hydroxypropyl cellulose (HPC), and hydroxypropyl methylcellulose (HPMC) were used as a stabilizer to improve the solubility of PAni in an aqueous medium. The water-soluble PAni-cellulose derivative was applied as a chemical sensor for hydrazine detection. The chemical structures and electrical conducting behaviours of PAni-cellulose derivatives were investigated using Fourier transform infrared (FTIR) and …
Peo-Ppo-Peo Surfactant Mixtures As Templates For Silicas With Very Large Cylindrical Mesopores At Ambient Temperature And With Helical Mesopores At Sub-Ambient Temperature,
2020
CUNY Graduate Center
Peo-Ppo-Peo Surfactant Mixtures As Templates For Silicas With Very Large Cylindrical Mesopores At Ambient Temperature And With Helical Mesopores At Sub-Ambient Temperature, Laurance Beaton
Dissertations, Theses, and Capstone Projects
The original research described herein concerns the synthesis of mesoporous silicas through a surfactant-templating method. The approach taken involved the use of a mixed surfactant system of two poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) surfactants, with one of the copolymers containing a much larger percentage of hydrophobic (PPO) blocks than the employed co-surfactant. Systematic adjustments of experimental parameters initially enabled the preparation of 2-D hexagonally ordered mesoporous silicas (SBA-15) of uncommonly large pore diameter at ambient temperature. Comparable silica was synthesized with and without temperature control. Additional adjustments to experimental parameters, including reduction of the relative amount of framework precursor used in …
Preparation And Characterisation Of Heat Treated Oil Palm-Empty Fruit Bunch/High Density Polyethylene Composites,
2020
Universiti Malaya
Preparation And Characterisation Of Heat Treated Oil Palm-Empty Fruit Bunch/High Density Polyethylene Composites, Nordin Nur Afifah
Student Works (2020-2029)
Natural fibre composites (NFCs) are composite materials, in which the reinforcing fibres are derived from renewable and carbon dioxide neutral resources such as wood or plants. NFC can be made by replacing synthetic fibres with various types of natural fibres. Oil palm empty fruit bunch (OPEFB) fibre and oil palm mesocarp fibre are two important types of fibrous materials left in the palm-oil industry. In this study, EFB will be used as a reinforcement to the high-density polyethylene (HDPE). EFB was heat-treated at 180°C using vacuum oven for one hour, extrusion compounded with HDPE at 10%, 20% and 30% weight …
Excitons In Self-Assembled Hybrid Systems Of Molecular Aggregate Light-Harvesting Nanotubes: Charge-Transfer Substrates And Solution-Stabilized Nanocomposites,
2020
CUNY Graduate Center
Excitons In Self-Assembled Hybrid Systems Of Molecular Aggregate Light-Harvesting Nanotubes: Charge-Transfer Substrates And Solution-Stabilized Nanocomposites, Kara Ng
Dissertations, Theses, and Capstone Projects
Delocalized Frenkel excitons-coherently-shared excitations among chromophores-are responsible for the remarkable effciency of supramolecular light-harvesting aggregates within photosynthetic organisms. Despite tremendous progress towards a deeper understanding of these photosynthetic complexes, as well as progress in the development of organic solar cells, the possibility of using bio-inspired molecular nanostructures for large-scale solar energy conversion has not been realized yet. The persistent limitations in translating natures design principles for applications in optoelectronic devices have been the supramolecular structures fragility, and the Frenkel excitons delicate nature. The structural instability, both dis-assembly and spontaneous re-assembly of aggregates. Analysis of the absorption spectrum of a model …
Pressure Driven Desalination Utilizing Nanomaterials,
2020
calpoly san luis obispo
Pressure Driven Desalination Utilizing Nanomaterials, Fangyou Xie
Master's Theses
Nanomaterials such as graphene oxide and carbon nanotubes, have demonstrated excellent properties for membrane desalination, including decrease of maintenance, increase of flux rate, simple solution casting, and impressive chemical inertness. Here, two projects are studied to investigate nanocarbon based membrane desalination. The first project is to prepare hybrid membranes with amyloid fibrils intercalated with graphene oxide sheets. The addition of protein amyloid fibrils expands the interlayer spacing between graphene oxide nanosheets and introduces additional functional groups in the diffusion pathways, resulting in increase of flux rate and rejection rate for the organic dyes. Amyloid fibrils also provide structural assistance to …
Detection Of Melamine Based On The Suppressed Anodic Response Of Uric Acid By A Au-Ag Nanoparticles Modified Glassy Carbon Electrode,
2020
National Changhua University of Education, Taiwan
Detection Of Melamine Based On The Suppressed Anodic Response Of Uric Acid By A Au-Ag Nanoparticles Modified Glassy Carbon Electrode, Yu-Hui Peng, Tsunghsueh Wu, Yang-Wei Lin
Journal of Food and Drug Analysis
We demonstrated a sensitive electrochemical method for the determination of non-electroactive melamine (Mel) using a modified glassy carbon electrode (GCE), with uric acid (UA) as the signal reporter. To increase the anodic response of UA, GCE was coated with Au–Ag nanoparticles and a Nafion thin film (Au–Ag/Nafion/GCE). The sensing mechanism was based on the competitive adsorption behavior of Mel on the Au–Ag/Nafion/GCE, which reduces the electroactive surface area of nanoparticles and thus hinders anodic response of UA. Under optimal conditions and the use of an analytical method of differential pulse voltammetry, this modified electrode detected Mel concentrations ranging from 2.5 …
Recent Progress In Bifunctional Catalysts For Zinc-Air Batteries,
2020
1. State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Environmental Science and Engineering, Donghua University, Shanghai 201620, China;2. University of Louisiana at Lafayette, Lafayette, LA 70504, USA;
Recent Progress In Bifunctional Catalysts For Zinc-Air Batteries, Neng-Neng Xu, Jin-Li Qiao
Journal of Electrochemistry
Zinc-air battery has attracted great attention from researchers due to its high energy density and power density, which is expected to be widely used in energy conversion and storage. Air electrode as the core area of oxygen catalytic reaction is the focus of the entire zinc-air battery research. Recently, many research achievements have been made in non-noble metal bifunctional catalysts/electrodes with high activity, low cost and abundant species. In this review, we mainly focus on the reaction mechanism and the recent progress in non-noble metal oxide catalyst, carbon-based catalyst, and carbon-based transition metal compound composite and self-supporting electrode. In addition, …
Research Progress Of Metal-Nitrogen-Carbon Catalysts Toward Oxygen Reduction Reaction Inm Changchun Institute Of Applied Chemistry,
2020
1. State Key Laboratory of Electroanalytica Chemistry, Changchun Institute of Applied Chemistry,Chinese Academy of Sciences University of Chinese Academy of Sciences, Changchun 130022,Jilin, China;2. University of Science and Technology of China, School of Applied Chemistry & Engineering, Hefei 230026, Anhui, China;
Research Progress Of Metal-Nitrogen-Carbon Catalysts Toward Oxygen Reduction Reaction Inm Changchun Institute Of Applied Chemistry, Ming-Jun Xu, Jie Liu, Jun-Jie Ge, Chang-Peng Liu, Wei Xing
Journal of Electrochemistry
The development of highly active and stable catalysts toward oxygen reduction reaction (ORR) has been facing severe challenges. In recent years, pyrolytic M-N-C catalysts and metal-organic framework derived materials made the performance of non-noble metal catalysts greatly improved, however, the molecular and atomic level understanding in the reaction active sites and the mechanism are still lacking. Here, we summarize the recent research progress made in the Changchun Institute of Applied Chemistry. We present a microporous metal-organic-framework confined strategy toward the preferable formation of ORR catalysts. Firstly, we studied the active site and proposed a new active site structure for the …
Electrochemical Carbon Dioxide Reduction In Flow Cells,
2020
Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University, Suzhou 215123, Jiangsu, China;
Electrochemical Carbon Dioxide Reduction In Flow Cells, Jia Fan, Na Han, Yan-Guang Li
Journal of Electrochemistry
Electrochemical carbon dioxide reduction (CO2RR) is an appealing approach to convert atmospheric CO2 to value-added fuels and industrial chemicals, and may play an important role during the transition to a carbon-neutral economy. In order to make this technology commercially viable, it is essential to pursue CO2RR in flow reactors instead of conventional H-type reactors, and to combine electrocatalyst development with system engineering. In this review, we overview the cell configurations and performance advantages of the two types of flow reactors, analyze their shortcomings, and discuss the effects of their different components including gas diffusion electrode …
Electrolyte Tailoring For Electrocatalytic Reduction Of Stable Molecules,
2020
Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Renewable Energy Conversion and Storage Center (ReCast), College of Chemistry, Nankai University, Tianjin 300071, China;
Electrolyte Tailoring For Electrocatalytic Reduction Of Stable Molecules, Jin-Han Li, Fang-Yi Cheng
Journal of Electrochemistry
Reduction of stable molecules such as CO2 and N2 is important process in electrochemical energy conversion and storage technologies for electrofuels production. However, for the inert nature of CO2/N2 molecule and competitive proton reduction in conventional aqueous electrolytes, selective electrochemical carbon/nitrogen fixation suffers from high overpotential, low reaction rate and low selectivity. While addressing these issues has witnessed substantial advances in electrocatalysts, much less attention has been placed on the electrolytes, which play an important role in regulating the local environment and thus the performance of catalysts under operating conditions. Rational design of electrolytes has …
Fuel Cell Performance Of Non-Precious Metal Based Electrocatalysts,
2020
1. Jiangsu Aoxin NEV Co., Ltd, Yancheng, Jiangsu, 224000, China;2. Department of Chemical and Biological Engineering, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China;3. Shanghai AI NEV Innovative Platform Co., Ltd, Shanghai, 201805, China;4. Yangtse Delta Academy of NEV CO.,LTD, Yancheng, Jiangsu, 224000, China;
Fuel Cell Performance Of Non-Precious Metal Based Electrocatalysts, Yan-Feng Zhang, Fei Xiao, Guang-Yu Chen, Min-Hua Shao
Journal of Electrochemistry
The commercialization of proton exchange membrane fuel cells (PEMFCs) is hindered by high cost and low durability of Pt based electrocatalysts. Developing efficient and durable non-precious metal catalysts is a promising approach to addressing these conundrums. Among them, transition metals dispersed in a nitrogen (N)-doped carbon support (M-N-C) show good oxygen reduction reaction activity. This article reviews recent progress in M-N-C catalysts development, focusing on the catalysts design, membrane electrode assembly fabrication, fuel cell performance, and durability testing. Template-assisted approach is an efficient way to synthesize M-N-C materials with homogeneously dispersed single atom active site and reduced metal particles, carbides …
Electrochemical Energy Storage And Conversion Based On Organic Electrodes,
2020
1. Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Institute of New Energy, Collaborative Innovation Center of Chemistry for Energy Materials, Fudan University, Shanghai 200433, China;2. School of Materials Science and Engineering, Nanchang Hangkong University, Nanchang 330063, Jiangxi, China;
Electrochemical Energy Storage And Conversion Based On Organic Electrodes, Jian-Hang Huang, Xiao-Li Dong, Zhao-Wei Guo, Yuan-Yuan Ma, Yan-Rong Wang, Yong-Gang Wang
Journal of Electrochemistry
Aqueous batteries have been considered to be a competitive candidate for large-scale energy storage. However, most of aqueous batteries adopt inorganic electrode materials with metallic elements, which are based on the reversible insertion of metal ions, making their application being highly hindered by limited cycle life, environmental issue, high cost and low reserves. On the other hand, organic electrode materials offer the advantages of abundant reserves, tunable structures, renewability and environmental benignity. Furthermore, the wide internal space enables these organics to flexibly store various charge carriers. Organics have been investigated as the alternative to inorganic electrode materials. Herein, we review …
Recent Progress On Enhancing Effect Of Nanosized Metals For Electrochemical Co2 Reduction,
2020
State Key Laboratory of Chemical Engineering, School of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China;
Recent Progress On Enhancing Effect Of Nanosized Metals For Electrochemical Co2 Reduction, Yu-Ning Zhang, Dong-Fang Niu, Shuo-Zhen Hu, Xin-Sheng Zhang
Journal of Electrochemistry
The electrochemical conversion of CO2 to chemical raw material for further utilization shows promising future to alleviate global warming and realize carbon cycle in nature, which is of great significance to the green chemistry and sustainable development. This review briefly introduces the advantages of CO2 electrochemical reduction (CO2ER) and its basic reaction principles, and summarizes the recent progress in a series of activity enhancement strategies based on nanosized metal catalysts. The influences of alloy effect, interface engineering, synergistic effect, surface defect engineering and support effect on the catalytic performance of nanosized metals for CO2ER …
Response Of Photoluminescence Of H-Terminated And Hydrosilylated Porous Si Powders To Rinsing And Temperature,
2020
West Chester University of Pennsylvania
Response Of Photoluminescence Of H-Terminated And Hydrosilylated Porous Si Powders To Rinsing And Temperature, Kurt W. Kolasinski, Joseph D. Swanson, Benjamin Roe, Teresa Lee
Chemistry Faculty Publications
The photoluminescence (PL) response of porous Si has potential applications in a number of sensor and bioimaging techniques. However, many questions still remain regarding how to stabilize and enhance the PL signal, as well as how PL responds to environmental factors. Regenerative electroless etching (ReEtching) was used to produce photoluminescent porous Si directly from Si powder. As etched, the material was H-terminated. The intensity and peak wavelength were greatly aected by the rinsing protocol employed. The highest intensity and bluest PL were obtained when dilute HCl(aq) rinsing was followed by pentane wetting and vacuum oven drying. Roughly half of the …
Doping Effects On Transition-Metal Silicides: Crystal Structures And Physical Properties Of Aluminium Doped Rhenium Silicide,
2020
Missouri State University
Doping Effects On Transition-Metal Silicides: Crystal Structures And Physical Properties Of Aluminium Doped Rhenium Silicide, Victoria Decocq
Graduate Theses/Dissertations
Semiconductive transition-metal silicides (e.g., ReSi) express weak thermoelectric properties. These properties can improve through n-type or p-type doping (e.g., Al), resulting in altered crystal structures. Binary rhenium silicide (ReSi1.75) exhibits promising thermoelectric properties and an intriguing crystal structure. Previous research has shown ReSi1.75 changes from a commensurate supercell MoSi2-type structure to an incommensurate superspace group structure, when doped with aluminium to ReAl0.074Si1.67. ReSi1.75 expresses a figure of merit (ZT) of 0.70 at 800°C, which improves to a ZT of 0.95 at 150°C for ReAl0.02Si1.75. Because of …
A Simple Predictive Model For Estimating Relative E-Cigarette Toxic Carbonyl Levels,
2020
Portland State University
A Simple Predictive Model For Estimating Relative E-Cigarette Toxic Carbonyl Levels, Shawna Vreeke, Xijing Zhu, Robert Strongin
Chemistry Faculty Publications and Presentations
E-cigarette devices are wide ranging, leading to significant differences in levels of toxic carbonyls in their respective aerosols. Power can be a useful method in predicting relative toxin concentrations within the same device, but does not correlate well to inter-device levels. Herein, we have developed a simple mathematical model utilizing parameters of an e-cigarette’s coil and wick in order to predict relative levels of e-liquid solvent degradation. Model 1, which is coil length/(wick surface area*wraps), performed in the moderate-to-substantial range as a predictive tool (R2 = 0.69). Twelve devices, spanning a range of coil and wick styles, were analyzed. …
