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University of South Carolina

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2014

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Articles 1 - 30 of 36

Full-Text Articles in Engineering

A Reversible And Stable Flake-Like Licoo2 Cathode For Lithium Ion Batteries, Tao Wei, Rui Zeng, Yongming Sun, Yunhui Huang, Kevin Huang Dec 2014

A Reversible And Stable Flake-Like Licoo2 Cathode For Lithium Ion Batteries, Tao Wei, Rui Zeng, Yongming Sun, Yunhui Huang, Kevin Huang

Faculty Publications

A dense and thick flake-like cathode structure was demonstrated to have a preferential crystallographic orientation for Li+ migration and a better tolerance to cracking, both of which enable a reversible and stable capacity at moderate rates from 0.1 to 2 C.


Direct Synthesis Of Methane From Co2-H2O Co-Electrolysis In Tubular Solid Oxide Electrolysis Cells, Long Chen, Fanglin Chen, Changrong Xia Dec 2014

Direct Synthesis Of Methane From Co2-H2O Co-Electrolysis In Tubular Solid Oxide Electrolysis Cells, Long Chen, Fanglin Chen, Changrong Xia

Faculty Publications

Directly converting CO2 to hydrocarbons offers a potential route for carbon-neutral energy technologies. Here we report a novel design, integrating the high-temperature CO2–H2O co-electrolysis and low-temperature Fischer–Tropsch synthesis in a single tubular unit, for the direct synthesis of methane from CO2 with a substantial yield of 11.84%.


Synthesis And Formation Mechanism Of Cuins2 Nanocrystals With A Tunable Phase, Chao Yu, Linlin Zhang, Long Tian, Dan Liu, Fanglin Chen, Cheng Wang Nov 2014

Synthesis And Formation Mechanism Of Cuins2 Nanocrystals With A Tunable Phase, Chao Yu, Linlin Zhang, Long Tian, Dan Liu, Fanglin Chen, Cheng Wang

Faculty Publications

Chalcopyrite CuInS2 (CIS) hierarchical structures composed of nanoflakes with a thickness of about 5 nm were synthesized by a facial solvothermal method. The thermodynamically metastable wurtzite phase CIS would be obtained by using InCl3 instead of In(NO3)3 as In precursor. The effects of the In precursor and the volume of concentrated HCl aqueous solution on the phases and morphologies of CIS nanocrystals have been systematically investigated. Experimental results indicated that the obtained phases of CIS nanocrystals were predominantly determined by precursor-induced intermediate products. The photocatalytic properties of chalcopyrite and wurtzite CIS in visible-light-driven degradation of …


Biphilic Nanoporous Surfaces Enabled Exceptional Drag Reduction And Capillary Evaporation Enhancement, Xianming Dai, Fanghao Yang, Ronggui Yang, Xinyu Huang, William A. Rigdon, Xiaodong Li, Chen Li Nov 2014

Biphilic Nanoporous Surfaces Enabled Exceptional Drag Reduction And Capillary Evaporation Enhancement, Xianming Dai, Fanghao Yang, Ronggui Yang, Xinyu Huang, William A. Rigdon, Xiaodong Li, Chen Li

Faculty Publications

Simultaneously achieving drag reduction and capillary evaporation enhancement is highly desired but challenging because of the trade-off between two distinct hydrophobic and hydrophilic wettabilities. Here, we report a strategy to synthesize nanoscale biphilic surfaces to endow exceptional drag reduction through creating a unique slip boundary condition and fast capillary wetting by inducing nanoscopic hydrophilic areas. The biphilic nanoporous surfaces are synthesized by decorating hydrophilic functional groups on hydrophobic pristine multiwalled carbon nanotubes. We demonstrate that the carbon nanotube-enabled biphilic nanoporous surfaces lead to a 63.1% reduction of the friction coefficient, a 61.7% wetting speed improvement, and up to 158.6% enhancement …


Host-Guest Interaction Dictated Selective Adsorption And Fluorescence Quenching Of A Luminescent Lightweight Metal-Organic Framework Toward Liquid Explosives, Dan Liu, Xiaojuan Liu, Yongxin Liu, Yang Yu, Fanglin Chen, Cheng Wang Oct 2014

Host-Guest Interaction Dictated Selective Adsorption And Fluorescence Quenching Of A Luminescent Lightweight Metal-Organic Framework Toward Liquid Explosives, Dan Liu, Xiaojuan Liu, Yongxin Liu, Yang Yu, Fanglin Chen, Cheng Wang

Faculty Publications

In this article, we report the successful preparation of a Mg-based luminescent MIL-53 metal–organic framework (MOF), namely [Mg2(BDC)2(BPNO)]·2DMF (1) (BDC = 1,4-benzene dicarboxylate, BPNO = 4,4’- dipyridyl-N,N’-dioxide, DMF = N,N-dimethylformamide) in a mixed solvent containing a 2 : 3 volume ratio of DMF and ethanol (EtOH) under solvothermal conditions. Desolvated compound 1a can be used as an absorbent for selective adsorption and separation of liquid explosives, including nitroaromatic (nitrobenzene (NB)) and nitroaliphatic (nitromethane (NM) and nitroethane (NE)) compounds, through single crystal-to-single crystal (SC–SC) transformations. As one of the weakly luminescent MOFs, the luminescence of compound 1a could be quenched by …


Influence Of Crystal Structure On The Electrochemical Performance Of A-Site-Deficient Sr 1-Xnb 0.1 Co 0.9 O 3-Δ Perovskite Cathodes, Yinlong Zhu, Ye Lin, Xuan Shen, Jaka Sunarso, Wei Zhou, Shanshan Jiang, Dong Su, Fanglin Chen, Zongping Shao Aug 2014

Influence Of Crystal Structure On The Electrochemical Performance Of A-Site-Deficient Sr 1-Xnb 0.1 Co 0.9 O 3-Δ Perovskite Cathodes, Yinlong Zhu, Ye Lin, Xuan Shen, Jaka Sunarso, Wei Zhou, Shanshan Jiang, Dong Su, Fanglin Chen, Zongping Shao

Faculty Publications

The creation of A-site cation defects within a perovskite oxide can substantially alter the structure and properties of its stoichiometric analogue. In this work, we demonstrate that by vacating 2 and 5% of A-site cations from SrNb0.1Co0.9O3−δ (SNC1.00) perovskites (Sr1−sNb0.1Co0.9O3−δ, s = 0.02 and 0.05; denoted as SNC0.98 and SNC0.95, respectively), a Jahn–Teller (JT) distortion with varying extents takes place, leading to the formation of a modified crystal lattice within a the perovskite framework. Electrical conductivity, electrochemical performance, chemical compatibility and microstructure of Sr …


Path Loss Modeling For V2v Communication On A Slope, Pengyu Liu, David W. Matolak, Bo Ai, Ruoyu Sun Jul 2014

Path Loss Modeling For V2v Communication On A Slope, Pengyu Liu, David W. Matolak, Bo Ai, Ruoyu Sun

Faculty Publications

Path loss modeling for both regular and irregular terrains is still gaining significant attention from researchers. A sloped terrain is one specific kind of an irregular terrain that-as far as we are aware-has not been completely studied. Although some results have been published for slope path loss modeling in cellular communication, an adequate model for the case when the transmitter (Tx) and the receiver (Rx) both have low-height antennas and are located on or near a slope does not exist. In this paper, for complete analysis of such conditions, we consider four scenarios: 1) two vehicles are located at opposite …


Phonon Confinement Using Spirally Designed Elastic Resonators In Discrete Continuum, Sourav Banerjee, Raiz U. Ahmed Jun 2014

Phonon Confinement Using Spirally Designed Elastic Resonators In Discrete Continuum, Sourav Banerjee, Raiz U. Ahmed

Faculty Publications

Periodic and chiral orientation of microstructures, here we call phononic crystals, have extraordinary capabilities to facilitate the innovative design of new generation metamaterials. Periodic arrangements of phononic crystals are capable of opening portals of non-passing, non-dispersive mechanical waves. Defying conventional design of regular periodicity, in this paper spirally periodic but chiral orientation of resonators are envisioned. Dynamics of the spirally connected resonators and the acoustic wave propagation through the spirally connected multiple local resonators are studied using fundamental physics. In present study the spiral systems with local resonators are assumed to be discrete media immersed in fluid. In this paper …


Uncertainty Quantification Driven Predictive Multi-Scale Model For Synthesis Of Mycotoxins, Sourav Banerjee, Gabriel A. Terejanu, Anindya Chanda Jun 2014

Uncertainty Quantification Driven Predictive Multi-Scale Model For Synthesis Of Mycotoxins, Sourav Banerjee, Gabriel A. Terejanu, Anindya Chanda

Faculty Publications

Many toxic molds synthesize and release an array of poisons, termed mycotoxins that have an enormous impact on human health, agriculture and economy [1]. These molds contaminate our buildings, indoor air and crops, cause life threatening human and animal diseases and reduce agricultural output [2]. In order to design appropriate approaches to minimize the detrimental effects of these fungi, it is essential to develop diagnostic methodologies that can rapidly and accurately determine based on fungal strains and their growth patterns, the extent of mycotoxin mediated damage caused to the environment.Here we developed a novel multi-scale predictive mathematical model that could …


Effect Of Z1/2, Eh5, And Ci1 Deep Defects On The Performance Of N-Type 4h-Sic Epitaxial Layers Schottky Detectors: Alpha Spectroscopy And Deep Level Transient Spectroscopy Studies, M. A. Mannan, S. K. Chaudhuri, K. V. Nguyen, K. C. Mandal Jun 2014

Effect Of Z1/2, Eh5, And Ci1 Deep Defects On The Performance Of N-Type 4h-Sic Epitaxial Layers Schottky Detectors: Alpha Spectroscopy And Deep Level Transient Spectroscopy Studies, M. A. Mannan, S. K. Chaudhuri, K. V. Nguyen, K. C. Mandal

Faculty Publications

No abstract provided.


Redox Stable Anodes For Solid Oxide Fuel Cells, Guoliang Xiao, Fanglin Chen Jun 2014

Redox Stable Anodes For Solid Oxide Fuel Cells, Guoliang Xiao, Fanglin Chen

Faculty Publications

Solid oxide fuel cells (SOFCs) can convert chemical energy from the fuel directly to electrical energy with high efficiency and fuel flexibility. Ni-based cermets have been the most widely adopted anode for SOFCs. However, the conventional Ni-based anode has low tolerance to sulfur-contamination, is vulnerable to deactivation by carbon build-up (coking) from direct oxidation of hydrocarbon fuels, and suffers volume instability upon redox cycling. Among these limitations, the redox instability of the anode is particularly important and has been intensively studied since the SOFC anode may experience redox cycling during fuel cell operations even with the ideal pure hydrogen as …


Simulation And Analysis Of Inhomogeneous Degradation In Large Format Limn2O4/ Carbon Cells, Yiling Dai, Long Cai, Ralph E. White Jun 2014

Simulation And Analysis Of Inhomogeneous Degradation In Large Format Limn2O4/ Carbon Cells, Yiling Dai, Long Cai, Ralph E. White

Faculty Publications

Degradation phenomena are not distributed uniformly in a large-format cell. To better understand the inhomogeneous degradation in large-format cells, a two-dimensional model was developed for a LiMn2O4 (LMO)/Carbon cell. The model includes both the non-uniform porous electrode properties and the electrode mismatch. The simulation results show that when the anode edge is extended over the cathode edge, the LMO particles near the edge suffer larger potential difference, larger charge/discharge depth, and higher insertion-induced stress. Therefore, the predicted loss of LMO is more pronounced near the edge as has been seen experimentally. The influence of different design adjustable …


Probing The Roles Of Polymeric Separators In Lithium-Ion Battery Capacity Fade At Elevated Temperatures, Jianchao Chen, Yongda Yan, Tao Sun, Yue Qi, Xiaodong Li May 2014

Probing The Roles Of Polymeric Separators In Lithium-Ion Battery Capacity Fade At Elevated Temperatures, Jianchao Chen, Yongda Yan, Tao Sun, Yue Qi, Xiaodong Li

Faculty Publications

The high temperature mechanical property of separators is very important for safety of lithium-ion batteries. However, the mechanical integrity of polymeric separators in lithium-ion batteries at elevated temperatures is still not well characterized. In this paper, the temperature dependent micro-scale morphology change of PP (polypropylene)-PE (polyethylene)-PP sandwiched separators (Celgard 2325) was studied by in-situ high temperature surface imaging using an atomic force microscope (AFM) coupled with power spectral density (PSD) analysis and digital image correlation (DIC) technique. Both PSD and DIC analysis results show that the PP phase significantly closes its pores by means of dilation of the nanofibrils surrounding …


A Novel Intermediate-Temperature All Ceramic Iron–Air Redox Battery: The Effect Of Current Density And Cycle Duration, Xuan Zhao, Xue Li, Yunhui Gong, Nansheng Xu, Kevin Huang May 2014

A Novel Intermediate-Temperature All Ceramic Iron–Air Redox Battery: The Effect Of Current Density And Cycle Duration, Xuan Zhao, Xue Li, Yunhui Gong, Nansheng Xu, Kevin Huang

Faculty Publications

We here report the energy storage characteristics of a new all ceramic iron–air redox battery comprising of a reversible solid oxide fuel cell as the charger/discharger and a Fe–FeOx redox couple as the chemical storage bed. The effects of current density and cycle duration on specific energy and round trip efficiency of the new battery have been systematically studied at 650°C and 550°C. The results explicitly show that current density is the most influential variable on the performance, signifying the importance of improving electrochemical performance of the reversible solid oxide fuel cell.


Defect Levels In Cu₂Znsn(Sₓse₁₋ₓ)₄ Solar Cells Probed By Current-Mode Deep Level Transient Spectroscopy, S. Das, S. K. Chaudhuri, R. N. Bhattacharya, K. C. Mandal May 2014

Defect Levels In Cu₂Znsn(Sₓse₁₋ₓ)₄ Solar Cells Probed By Current-Mode Deep Level Transient Spectroscopy, S. Das, S. K. Chaudhuri, R. N. Bhattacharya, K. C. Mandal

Faculty Publications

No abstract provided.


Characterization Of 3d Interconnected Microstructural Network In Mixed Ionic And Electronic Conducting Ceramic Composites, William M. Harris, Kyle S. Brinkman, Ye Lin, Dong Su, Alex P. Cocco, Arata Nakajo, Matthew B. Degostin, Yu-Chen Karen Chen-Wiegart, Jun Wang, Fanglin Chen, Yong S. Chu, Wilson K. S. Chiu May 2014

Characterization Of 3d Interconnected Microstructural Network In Mixed Ionic And Electronic Conducting Ceramic Composites, William M. Harris, Kyle S. Brinkman, Ye Lin, Dong Su, Alex P. Cocco, Arata Nakajo, Matthew B. Degostin, Yu-Chen Karen Chen-Wiegart, Jun Wang, Fanglin Chen, Yong S. Chu, Wilson K. S. Chiu

Faculty Publications

The microstructure and connectivity of the ionic and electronic conductive phases in composite ceramic membranes are directly related to device performance. Transmission electron microscopy (TEM) including chemical mapping combined with X-ray nanotomography (XNT) have been used to characterize the composition and 3-D microstructure of a MIEC composite model system consisting of a Ce0.8Gd0.2O2 (GDC) oxygen ion conductive phase and a CoFe2O4 (CFO) electronic conductive phase. The microstructural data is discussed, including the composition and distribution of an emergent phase which takes the form of isolated and distinct regions. Performance implications are considered …


A Sinteractive Ni-Bazr0.8Y0.2O3-Δ Composite Membrane For Hydrogen Separation, Shumin Fang, Siwei Wang, Kyle S. Brinkman, Fanglin Chen Apr 2014

A Sinteractive Ni-Bazr0.8Y0.2O3-Δ Composite Membrane For Hydrogen Separation, Shumin Fang, Siwei Wang, Kyle S. Brinkman, Fanglin Chen

Faculty Publications

BaZr0.8Y0.2O3−δ (BZY) is an excellent candidate material for hydrogen permeation membranes due to its high bulk proton conductivity, mechanical robustness, and chemical stability in H2O- and CO2-containing environments. Unfortunately, the use of BZY as a separation membrane has been greatly restrained by its highly refractory nature, poor grain boundary proton conductivity, high number of grain boundaries resulting from limited grain growth during sintering, as well as low electronic conductivity. These problems can be resolved by the fabrication of a Ni–BZY composite membrane with large BZY grains, which requires the development …


Kinetic Modeling Of Self-Hydrolysis Of Aqueous Nabh4 Solutions By Model-Based Isoconversional Method, Rajasree Retnamma, A. Q. Novais, C. M. Rangel, Lin Yu, Michael A. Matthews Apr 2014

Kinetic Modeling Of Self-Hydrolysis Of Aqueous Nabh4 Solutions By Model-Based Isoconversional Method, Rajasree Retnamma, A. Q. Novais, C. M. Rangel, Lin Yu, Michael A. Matthews

Faculty Publications

The present work reports the kinetic modeling of self-hydrolysis of non-buffered, non-stabilized NaBH4 solutions by model-based isoconversional method. The overall kinetics is described by a „reaction-order‟ model in a practical operating window of 10-20 wt% NaBH4 solutions at 25-80 C and 0-50% conversions. The apparent activation energy and pre-exponential factor are interrelated through a kinetic compensation effect (KCE). The apparent reaction order remains constant at a given temperature irrespective of extent of conversion and decreases with increase in temperature. It decreases from firstorder to 0.26 with increase in temperature from 25 to 80 C. The apparent activation energy is found …


Large-Scale Site And Frequency Diversity In Urban Peer-To-Peer Channels For Six Public Safety Frequency Bands, David W. Matolak, Kate A. Remley, Christopher L. Holloway, Qian Zhang, Qiong Wu Apr 2014

Large-Scale Site And Frequency Diversity In Urban Peer-To-Peer Channels For Six Public Safety Frequency Bands, David W. Matolak, Kate A. Remley, Christopher L. Holloway, Qian Zhang, Qiong Wu

Faculty Publications

We report on peer-to-peer large-scale wireless channel characteristics for an urban environment in six public-safety bands, for five simultaneous receiving sites. Results are based upon measurements taken in Denver in July 2009 with stationary receivers and a pedestrian transmitter. The six frequencies at which we measured are (in MHz) 430, 750, 905, 1834, 2400, and 4860. We quantify both site and frequency diversity, and show that 5-site selection yields minimum average gains of 15 dB in mean received power levels; 5-site selection diversity also reduces received power variation by 17-29 dB, depending on frequency. Frequency diversity yields similar gains. By …


Investigation Of The High-Temperature Redox Chemistry Of Sr2Fe1.5Mo0.5O6-Δ Via In Situ Neutron Diffraction, Daniel E. Bugaris, Jason P. Hodges, Ashfia Hug, W. Michael Chance, Andreas Heyden, Fanglin Chen, Hans-Conrad Zur Loye Mar 2014

Investigation Of The High-Temperature Redox Chemistry Of Sr2Fe1.5Mo0.5O6-Δ Via In Situ Neutron Diffraction, Daniel E. Bugaris, Jason P. Hodges, Ashfia Hug, W. Michael Chance, Andreas Heyden, Fanglin Chen, Hans-Conrad Zur Loye

Faculty Publications

Crystallographic structural changes were investigated for Sr2Fe1.5Mo0.5O6−δ, an electrode material for symmetric solid oxide fuel cells. The samples of this material were heated and cooled in wet hydrogen and wet oxygen atmospheres, to simulate the reducing and oxidizing conditions experienced under actual fuel cell operating conditions, and their structures and oxygen contents were determined using in situ powder neutron diffraction. The existence of a reversible tetragonal to cubic phase transition was established to occur between room temperature and 400 °C, both on heating and cooling in either oxygen or hydrogen. The …


A Reactor Model For Hydrogen Generation From Sodium Borohydride And Water Vapor, Lin Yu, Michael A. Matthews Mar 2014

A Reactor Model For Hydrogen Generation From Sodium Borohydride And Water Vapor, Lin Yu, Michael A. Matthews

Faculty Publications

This paper reports new data on the production of hydrogen from water vapor plus NaBH4, or NaBH4 þ 10% CoCl2. Data were collected with the aid of an isothermal semi-batch reactor with in-situ H2 rate measurement. The reaction of NaBH4 to generate H2 proceeds via three steps: deliquescence, dissolution and reaction. The deliquescence regime of NaBH4 in the presence of 10 weight percent CoCl2 is defined. The H2 yield is quantified at various reaction conditions (reaction temperature 70-120 C, relative humidity 31-69%). CoCl2 significantly accelerates the rate of H2 production compared to deliquescence + reaction of pure NaBH4. It is …


Preparation Of Radiation-Grafted Powders For Use As Anion Exchange Ionomers In Alkaline Polymer Electrolyte Fuel Cells, Simon D. Poynton, Robert C. T. Slade, Travis J. Omasta, William E. Mustain, Ricardo Escudero-Cid, Pilar Ocón, John R. Varcoe Feb 2014

Preparation Of Radiation-Grafted Powders For Use As Anion Exchange Ionomers In Alkaline Polymer Electrolyte Fuel Cells, Simon D. Poynton, Robert C. T. Slade, Travis J. Omasta, William E. Mustain, Ricardo Escudero-Cid, Pilar Ocón, John R. Varcoe

Faculty Publications

A novel alkaline exchange ionomer (AEI) was prepared from the radiation-grafting of vinylbenzyl chloride (VBC) onto poly(ethylene-co-tetrafluoroethylene) [ETFE] powders with powder particle sizes of less than 100 μm diameter. Quaternisation of the VBC grafted ETFE powders with trimethylamine resulted in AEIs that were chemically the same as the ETFE-based radiation-grafted alkaline anion exchange membranes (AAEM) that had been previously developed for use in low temperature alkaline polymer electrolyte fuel cells (APEFC). The integration of the AEI powders into the catalyst layers (CL) of both electrodes resulted in a H2/O2 fuel cell peak power density of 240 mW cm−2 …


Modulation Of Leukocyte Infiltration And Phenotype In Microporous Tissue Engineering Scaffolds Via Vector Induced Il-10 Expression, R. Michael Gower, Ryan M. Boehler, Samira M. Azarin, Christine F. Ricci, Joshua N. Leonard, Lonnie D. Shea Feb 2014

Modulation Of Leukocyte Infiltration And Phenotype In Microporous Tissue Engineering Scaffolds Via Vector Induced Il-10 Expression, R. Michael Gower, Ryan M. Boehler, Samira M. Azarin, Christine F. Ricci, Joshua N. Leonard, Lonnie D. Shea

Faculty Publications

Biomaterial scaffolds are central to many tissue engineering strategies as they create a space for tissue growth and provide a support for cell adhesion and migration. However, biomaterial implantation results in unavoidable injury resulting in an inflammatory response, which can impair integration with the host and tissue regeneration. Toward the goal of reducing inflammation, we investigated the hypothesis that a lentiviral gene therapy-based approach to localized and sustained IL-10 expression at a scaffold could modulate the number, relative proportions, and cytokine production of infiltrating leukocyte populations. Flow cytometry was used to quantify infiltration of six leukocyte populations for 21 days …


Sr3<−3xNa3xSi3O9−1.5x (X = 0.45) As A Superior Solid Oxide-Ion Electrolyte For Intermediate Temperature-Solid Oxide Fuel Cells, Tao Wei, Preetam Singh, Yunhui Gong, John B. Goodenough, Yunhui Huang, Kevin Huang Jan 2014

Sr3<−3xNa3xSi3O9−1.5x (X = 0.45) As A Superior Solid Oxide-Ion Electrolyte For Intermediate Temperature-Solid Oxide Fuel Cells, Tao Wei, Preetam Singh, Yunhui Gong, John B. Goodenough, Yunhui Huang, Kevin Huang

Faculty Publications

We here report that a newly discovered superior oxide-ion conductor Sr3−3xNa3xSi3O9−1.5x (x = 0.45) (SNS) demonstrates full potential to be a practical solid electrolyte for intermediate temperature-solid oxide fuel cells (IT-SOFCs). It exhibits the highest oxide-ion conductivity with the lowest activation energy among all the chemically stable solid oxide-ion conductors reported. The ionic conductivity is stable over a broad range of partial pressures of oxygen (10−30 to 1 atm) for an extended period of time. A SOFC based on a 294 μm thick SNS-electrolyte produces peak power densities …


One-Step Production Of Long-Chain Hydrocarbons From Waste-Biomass-Derived Chemicals Using Bi-Functional Heterogeneous Catalysts, Cun Wen, Elizabeth A. Barrow, Jason R. Hattrick-Simpers, Jochen A. Lauterbach Jan 2014

One-Step Production Of Long-Chain Hydrocarbons From Waste-Biomass-Derived Chemicals Using Bi-Functional Heterogeneous Catalysts, Cun Wen, Elizabeth A. Barrow, Jason R. Hattrick-Simpers, Jochen A. Lauterbach

Faculty Publications

n this study, we demonstrate the production of long-chain hydrocarbons (C8+) from 2-methylfuran (2MF) and butanal in a single step reactive process by utilizing a bi-functional catalyst with both acid and metallic sites. Our approach utilizes a solid acid for the hydroalkylation function and as a support as well as a transition metal as hydrodeoxygenation catalyst. A series of solid acids was screened, among which MCM-41 demonstrated the best combination of activity and stability. Platinum nanoparticles were then incorporated into the MCM-41. The Pt/MCM-41 catalyst showed 96% yield for C8+ hydrocarbons and the catalytic performance was stable …


Self-Healing Catalysts: Co3O4 Nanorods For Fischer-Tropsch Synthesis, Cun Wen, Darrius D. Dunbar, Xin Zhang, Jochen A. Lauterbach, Jason R. Hattrick-Simpers Jan 2014

Self-Healing Catalysts: Co3O4 Nanorods For Fischer-Tropsch Synthesis, Cun Wen, Darrius D. Dunbar, Xin Zhang, Jochen A. Lauterbach, Jason R. Hattrick-Simpers

Faculty Publications

We combine kinetic and spectroscopic data to demonstrate the concept of a self-healing catalyst, which effectively eliminates the need for catalyst regeneration. The observed self-healing is triggered by controlling the crystallographic orientation at the catalyst surface.


Influence Of Crystal Structure On The Electrochemical Performance Of A-Site-Deficient Sr1-SNb0.1Co0.9O3-Δ Perovskite Cathodes, Yinlong Zhu, Ye Lin, Xuan Shen, Jaka Sunarso, Wei Zhou, Shanshan Jiang, Dong Su, Fanglin Chen, Zongping Shao Jan 2014

Influence Of Crystal Structure On The Electrochemical Performance Of A-Site-Deficient Sr1-SNb0.1Co0.9O3-Δ Perovskite Cathodes, Yinlong Zhu, Ye Lin, Xuan Shen, Jaka Sunarso, Wei Zhou, Shanshan Jiang, Dong Su, Fanglin Chen, Zongping Shao

Faculty Publications

The creation of A-site cation defects within a perovskite oxide can substantially alter the structure and properties of its stoichiometric analogue. In this work, we demonstrate that by vacating 2 and 5% of Asite cations from SrNb0.1Co0.9O3-δ (SNC1.00) perovskites (Sr1-sNb0.1Co0.9O3-δ,s = 0.02 and 0.05; denoted as SNC0.98 and SNC0.95, respectively), a Jahn–Teller (JT) distortion with varying extents takes place, leading to the formation of a modified crystal lattice within a the perovskite framework. Electrical conductivity, electrochemical performance, chemical compatibility and microstructure of Sr1-sNb0.1Co …


A Platinum Nanowire Network As A Highly Effective Current Collector For Intermediate Temperature Solid Oxide Fuel Cells, Hanping Ding, Xingjian Xue Jan 2014

A Platinum Nanowire Network As A Highly Effective Current Collector For Intermediate Temperature Solid Oxide Fuel Cells, Hanping Ding, Xingjian Xue

Faculty Publications

We report the fabrication and evaluation of a platinum nanowire network as a highly efficient current collector for solid oxide fuel cells (SOFCs). The ink of carbon-black supported platinum nanoparticles was sprayed onto the cathode. After firing, the carbon black was oxidized and disappeared as carbon dioxide gas while the platinum nanoparticles connect with one another, forming a tree-branch-like nanowire network. The diameters of the nanowires range from 100 nm to 400 nm. Compared to a conventional platinum paste current collector, the polarization resistance of the PrBaCo2O5+δ (PBCO) cathode with a nanowire current collector was reduced …


Design, Fabrication, And Properties Of 2-2 Connectivity Cement/Polymer Based Piezoelectric Composites With Varied Piezoelectric Phase Distribution, Xu Dongyu, Cheng Xin, Sourav Banerjee, Huang Shifeng Jan 2014

Design, Fabrication, And Properties Of 2-2 Connectivity Cement/Polymer Based Piezoelectric Composites With Varied Piezoelectric Phase Distribution, Xu Dongyu, Cheng Xin, Sourav Banerjee, Huang Shifeng

Faculty Publications

The laminated 2-2 connectivity cement/polymer based piezoelectric composites with variedpiezoelectric phase distribution were fabricated by employing Lead Zirconium Titanate ceramicas active phase, and mixture of cement powder, epoxy resin, and hardener as matrix phase with a mass proportion of 4:4:1. The dielectric, piezoelectric, and electromechanical coupling properties of the composites were studied. The composites with large total volume fraction ofpiezoelectric phase have large piezoelectric strain constant and relative permittivity, and thepiezoelectric and dielectric properties of the composites are independent of the dimensional variations of the piezoelectric ceramic layer. The composites with small total volume fraction of piezoelectric phase have large …


There Can Be Turbulence In Microfluidics At Low Reynolds Number, Guiren Wang, F. Yang, Wei Zhao Jan 2014

There Can Be Turbulence In Microfluidics At Low Reynolds Number, Guiren Wang, F. Yang, Wei Zhao

Faculty Publications

Turbulence is commonly viewed as a type of macroflow, where the Reynolds number (Re) has to be sufficiently high. In microfluidics, when Re is below or on the order of 1 and fast mixing is required, so far only chaotic flow has been reported to enhance mixing based on previous publications since turbulence is believed not to be possible to generate in such a low Re microflow. There is even a lack of velocimeter that can measure turbulence in microchannels. In this work, we report a direct observation of the existence of turbulence in microfluidics with Re on the order …