Electrical and Computer Engineering Commons^™

Recycling Mf Solid Waste Into Mesoporous Nitrogen-Doped Carbon With Iron Carbide Complex In Graphitic Layers As An Efficient Catalyst For Oxygen Reduction Reaction, Can-Yun Zhao, Lin Huang, Yong You, Ying-Fang Yao, Xiao-Gang Su, Hong Wan, Jian-Guo Liu, Cong-Ping Wu

Journal of Electrochemistry

Nitrogen-doped carbon materials with iron ions are known as catalytic growth agents for the oxygen reduction reaction (ORR) in fuel cells, but the design and synthesis of high-performance and low-cost catalysts still remain a significant challenge. Herein, we present a cost-effective approach to dispose of MF solid waste as the precursor for the synthesis of MCFes catalyst with the favorable structure features such as the high specific surface area, abundant active sites and suitable pore structure. The results showed that the MCFe-10/10/2 had specific surface area as high as 780.7 m²•g^-1 and high efficient catalytic activity comparable …

Syntheses Of Carbon Paper Supported High-Index Faceted Pt Nanoparticles And Their Performance In Direct Formic Acid Fuel Cells, Long Huang, Mei Zhan, Yu-Cheng Wang, Yan-Fen Lin, Shuo Liu, Ting Yuan, Hui Yang, Shi-Gang Sun

Journal of Electrochemistry

Direct formic acid fuel fuels (DFAFCs) are promising energy source for portable electronic devices. Palladium (Pd) is more active than platinum (Pt) for the formic acid electrooxidation. However, the stability of Pd is much poorer than that of Pt. Unfortunately, the ultra-low natural abundance of the Pt makes it extremely expensive and limits its application as a fuel cell catalyst. Boosting both the activity and stability of Pt nanoparticles to enhance their efficiency is urgent. As previous works illustrated, nanoparticles enclosed with high-index facets usually bare a higher activity toward fuel cell related reactions than those nanoparticles with low-index facet. …

Synthesis Of Structurally Ordered Platinum-Iron Catalysts With Enhanced Oxygen Reduction Reaction Activity, Ye-Zheng Cai, Ming-Chuan Luo, Fang-Hui Wang, Zhao-Nan Sun, Hong Zhu

Journal of Electrochemistry

To improve oxygen reduction reaction catalytic activity of the precious metals platinum for fuel cell, the precursors of carbon-supported structurally disordered platinum-iron alloy (D-Pt₃Fe/C and D-PtFe/C) catalysts with different compositions were synthesized via a modified polyol reduction method. Then, by optimizing the annealing conditions in the inert gas, we turned the structurally disordered platinum-iron alloy to the structurally ordered platinum-iron alloy (O-Pt₃Fe/C and O-PtFe/C) catalysts. The structural characterizations of the as-prepared catalysts were performed by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), inductively coupled plasma-atomic emission spectroscopy (ICP-AES), and X-ray photoelectron spectroscopy (XPS). The results …

Preparation And Performance Of 3d Graphene Type Porous Carbon Employing Nano Fe(Oh)3 As Template For Oxygen Reduction Catalyst, Chong-Yun Sun, Zhong-Fang Li, Xue-Wei Lu, Xi-Zhan Zhong, Yu-Rong Liu

Journal of Electrochemistry

The 3D graphene type porous carbon was prepared using coal tar pitch as carbon source and nano Fe(OH)₃ as template. Optimal conditions for the catalytic oxygen reduction performance were determined as: the mass ratio of coal tar, nano Fe(OH)₃ and KOH is 6:8:4; the pyrolysis temperature is 800 ^oC. SEM images show that the products have uniformly porous structure. TEM images demonstrate that the products are porous with foam shapes. HRTEM images further indicate that the products have formed several-layers 3D graphene structure, which are also supported by XRD and Raman data, and the pore size mainly …

Recent Progress In Non-Precious Metal Oxygen Reduction Reaction Catalysts With An Encapsulation Structure, Mei-Ling Xiao, Jian-Bing Zhu, Chang-Peng Liu, Jun-Jie Ge, Wei Xing

Journal of Electrochemistry

Platinum-based materials, the state-of-the-art catalysts for fuel cells, suffer from prohibitive costs, limited resources and insufficient durability. Accordingly, tremendous efforts were made in searching for efficient, durable and inexpensive alternatives to precious-metal electrocatalysts for the oxygen reduction reaction (ORR). Transition-metals (Fe, Co)/nitrogen co-doped hybrids, heteroatom (N, P, S, F, et al) doped carbons and composites with transition-metals encapsulated in graphitic layers are reported as the most efficient non-precious metal ORR catalysts. Among the various non-precious metal ORR catalysts, transition-metals encased in graphitic layer catalysts are a novel type of catalysts for ORR with high activity and durability, and thus, the …

Special Issue: Electrocatalyst And Electrocatalysis In Fuel Cells Preface, Zi-Dong Wei

Journal of Electrochemistry

In the last two decades, fuel cells captured worldwide attention as a promising renewable emission-free technology to meet the increasing demand of clean energy for stationary and transportation applications. Currently, platinum (Pt) is the most widely used electrocatalyst for both hydrogen oxidation reaction (HOR) at anode and oxygen reduction reaction (ORR) at cathode. However, the high-cost and scarcity of Pt have become the major challenges for commercialization of fuel cells. To overcome the above mentioned problems, great progress has been made in developing more active electrocatalysts on the basis of Pt-based and Pt-free electro catalysts. For the Pt-based electrocatalysts, composition, …

Rambling Between "Zhong Yong" And "Catalysis", Zi-Dong Wei

Journal of Electrochemistry

“Zhong Yong” represents a traditional Chinese wisdom, which was first proposed by Confucius and continuously richened by his followers. “Zhong Yong” pursues the balances among all kinds of contradictions, and insists that neither “too much” nor “not enough” is good. For a successful catalyst, on which the adsorption of reactants must be not so strong and not so weak either. On this point of view, there are the same pursuits for “Zhong Yong” and catalysis. In this paper, the author starts his story with a conversation between Confucius and his student, followed by 3 interesting stories happening in the ancient …

Mini-Review: Possible Applications Of Scanning Electrochemical Microscopy (Secm) In Characterizations Of Oxygen Reduction Reaction And Oxygen Evolution Reaction, Xing-Xing Chen

Journal of Electrochemistry

Scanning electrochemical microscopy (SECM) has been proved to be a unique technique for combinatorial screening of localized phenomena for different electrocatalysts potentially used in new energy conversion and storage systems. This mini-review provides a brief summary of different SECM working modes, such as direct mode, feedback mode, generation-collection mode, redox competition mode and noise mode, which are especially applied for characterizing the oxygen reactions. Particularly, a series of important development in SECM screening of electrocatalysts for oxygen reduction reaction and oxygen evolution reaction from the author and W. Schuhmann’s group in Germany has been highlighted and overviewed. Finally, some prospects …

Recent Progresses In Molybdenum-Based Electrocatalysts For The Hydrogen Evolution Reaction, Ze-Xing Wu, Jie Wang, Jun-Po Guo, Jing Zhu, De-Li Wang

Journal of Electrochemistry

Electrochemical catalytic production of hydrogen has been considered as a promising and sustainable strategy for clean and renewable energy technologies. Molybdenum-based non noble metal catalysts for the hydrogen evolution reaction have attracted extensive attention due to its effective catalytic performance. In this review, the recent progresses in molybdenum-carbide, phosphide, nitride and sulfide electrocatalysts are presented. In addition, the strategies to improve the catalytic performance are analyzed and the prospects for the future development trends are expected.

Multi-Scaled Carbon Supported Platinum As A Stable Electrocatalyst For Oxygen Reduction Reaction, Yu-Ping Li, Lu-Hua Jiang, Su-Li Wang, Gong-Quan Sun

Journal of Electrochemistry

The stability of carbon supports is essential for electrocatalysts of fuel cells. Herein, the mesoporous carbon with the high graphitic degree (highly graphitic mesoporous carbon, HGMC) was synthesized by using resorcinol as the carbon precursor, SiO2 as the templates and urea as the reducing agent. The as-prepared HGMC was characterized by XRD, Raman spectroscopy, TEM, N2 adsorption. The stability of HGMC was evaluated by mimicking the start-up/shut-down conditions of fuel cells in a three-electrode system referring to the NREL standard. The obtained HGMC is of moderate surface area (187.4 m²•g^-1) and is chemically stable under potentiodynamic …

A Study Of Single Scattering Of Scatterer At Various Orientation Angles With Equivalence Principle Algorithm, Chan Fai Lum, Hong Tat Ewe, Fu-Xin, Li (Lijun) Jun Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

It is common that spherical scatterers are used to represent air bubbles or brine inclusions embedded in the snow or sea ice layer. This physical configuration is then solved using radiative transfer theory to obtain backscattering coefficient from the snow or sea ice layer. With the advent of new techniques in computational electromagnetics, the typical theoretical model of single layer of snow or sea ice can be easily extended to consider types of scatterers which are of other shapes or irregular shapes. A computational electromagnetic method based on equivalence principle algorithm can be incorporated into existing theoretical model to calculate …

Impact Of Wind Generation On Dynamic Voltage Characteristics Of Power Systems, Luis Badesa

Electronic Theses and Dissertations

In recent times there has been an increasing interest in renewable energies due to public awareness of the negative effects on the environment of conventional electricity generation resources like coal and oil, and several policies have been enacted requiring progressive reduction of fossil-fuel-based generation. Due to some favorable characteristics of wind over other renewables, wind power has grown considerably in the last two decades.

Integration of wind generation into the existing power grids poses significant challenges. The limited reactive power capability that wind turbines have can cause several problems, such as important voltage drops or rises in the system. Therefore, …

Memory And Information Processing In Recurrent Neural Networks, Alireza Goudarzi, Sarah Marzen, Peter Banda, Guy Feldman, Matthew R. Lakin, Christof Teuscher, Darko Stefanovic

Electrical and Computer Engineering Faculty Publications and Presentations

Recurrent neural networks (RNN) are simple dynamical systems whose computational power has been attributed to their short-term memory. Short-term memory of RNNs has been previously studied analytically only for the case of orthogonal networks, and only under annealed approximation, and uncorrelated input. Here for the first time, we present an exact solution to the memory capacity and the task-solving performance as a function of the structure of a given network instance, enabling direct determination of the function-structure relation in RNNs. We calculate the memory capacity for arbitrary networks with exponentially correlated input and further related it to the performance of …

Hallmarks Of The Mott-Metal Crossover In The Hole-Doped Pseudospin-1/2 Mott Insulator Sr2Iro4, Yue Cao, Qiang Wang, Justin A. Waugh, Theodore J. Reber, Haoxiang Li, Xiaoqing Zhou, Stephen Parham, S. -R. Park, Nicholas C. Plumb, Eli Rotenberg, Aaron Bostwick, Jonathan D. Denlinger, Tongfei Qi, Michael A. Hermele, Gang Cao, Daniel S. Dessau

Physics and Astronomy Faculty Publications

The physics of doped Mott insulators remains controversial after decades of active research, hindered by the interplay among competing orders and fluctuations. It is thus highly desired to distinguish the intrinsic characters of the Mott-metal crossover from those of other origins. Here we investigate the evolution of electronic structure and dynamics of the hole-doped pseudospin-1/2 Mott insulator Sr₂IrO₄. The effective hole doping is achieved by replacing Ir with Rh atoms, with the chemical potential immediately jumping to or near the top of the lower Hubbard band. The doped iridates exhibit multiple iconic low-energy features previously observed …

Instructables.Com As A Tool To Improve Student Outcomes And Promote Community Engagement (Work-In-Progress), Andrew Danowitz

Electrical Engineering

Project-based Learning (PBL) has become a popular pedagogical tool in Engineering. Projects force students to put theory learned in lecture into practice, exposes students to some of the nonidealities of real systems (imperfect instruments, uncooperative systems, etc.) that are difficult to convey in lecture or homework, and ideally motivates students by showing how course material is related real-world engineering problems. This work discusses my preliminary and ongoing research into using Instructables.com—a user-content generated website of “Do It Yourself” tutorials—as a tool to help amplify the benefits students derive from PBL. Specifically, I require students to document their projects in an …

Ac Power Monitoring System Provides Individual Circuit Energy Consumption Data, Jared L. Newman, Grayson H. Dearing, Luke M. Tomlinson, Frederick G. Harmon

The Research and Scholarship Symposium (2013-2019)

Motivated by high energy costs, people and organizations want to cut back on their energy consumption. However, the only feedback consumers typically receive is a monthly bill listing their total electricity usage (in kWh). Some companies have begun developing systems that allow households and organizations to monitor their energy usage for individual circuits. Available systems are expensive so a CU engineering senior design team has designed, fabricated, and tested a system for use at Cedarville University. The AC power monitoring system has the ability to measure energy consumption for each individual circuit in the breaker panel, store the data, and …

Solar Tracking And Lighting Design For A Multimedia Sculpture, Alexandra Ferguson

Honors Theses

A lighting system utilizing solar energy was built to illuminate a wireframe multimedia sculpture. Increased power generation from the solar cells was achieved using a solar tracking mechanism. Color-selectable light emitting diodes were used to provide the user with unlimited customization options. A digital control system was designed using an Arduino® microcontroller to configure the color of the lights and the positioning of the solar panel. The sculpture will create a sense of community and sustainability among students at the school.

Free-Hand Scanning And Imaging, Joseph T. Case, Mohammad Tayeb Ahmad Ghasr, R. Zoughi

Electrical and Computer Engineering Faculty Research & Creative Works

Wideband synthetic aperture radar (SAR) imaging. A probe transmits a signal through its aperture incident to an object located in a medium of interest remotely from the probe. The probe receives through the aperture a plurality of nonuniformly sampled reflected signals from the object as the probe moves in a measurement plane located a predetermined distance from the object. A processor executes a SAR-based reconstruction algorithm to generate an image.

Life Alert System For Vulnerable Adults Who Live Alone, Bohyun Ahn

Undergraduate Research Symposium

As medical technology and the standard of living have improved, the number of vulnerable adults who live alone has increased. Asking for help themselves may be impossible if they have a medical or life issue. Some accidents may go unnoticed for individuals living alone. When accidents regarding vulnerable adults occur, it may take days or weeks to become known by family or neighbors. To solve this problem, a life alert system was designed for vulnerable adults in their homes. To demonstrate the system, A fusion of different sensors were set up in a booth to detect the user’s motion over …

Autonomous Methods In The Application Of Simple Swarm Capabilities, Joseph Watt Iii

GS4 Georgia Southern Student Scholars Symposium

Swarm technology is a relatively new aspect to the drone industry. It involves multiple drones being able to communicate with each other and relay this back to the user. From this standpoint one operator can control all of them at once while only giving directions to one or more. This involves the use of different autonomous algorithms, similar to autopilot where programs fly the plane, that relay to one another on what adjustments to make or where to go. This idea is very useful in search and rescue operations where it might be too dangerous to insert a human. Also …