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Articles 1 - 30 of 37
Full-Text Articles in Physical Sciences and Mathematics
Characteristics And Assessing Biological Risks Of Airborne Bacteria In Waste Sorting Plant, Abbas Norouzian Baghani, Somayeh Golbaz, Gholamreza Ebrahimzadeh, Marcelo I. Guzman, Mahdieh Delikhoon, Mehdi Jamshidi Rastani, Abdullah Barkhordari, Ramin Nabizadeh
Characteristics And Assessing Biological Risks Of Airborne Bacteria In Waste Sorting Plant, Abbas Norouzian Baghani, Somayeh Golbaz, Gholamreza Ebrahimzadeh, Marcelo I. Guzman, Mahdieh Delikhoon, Mehdi Jamshidi Rastani, Abdullah Barkhordari, Ramin Nabizadeh
Chemistry Faculty Publications
Examining the concentration and types of airborne bacteria in waste paper and cardboard sorting plants (WPCSP) is an urgent matter to inform policy makers about the health impacts on exposed workers. Herein, we collected 20 samples at 9 points of a WPCSP every 6 winter days, and found that the most abundant airborne bacteria were positively and negatively correlated to relative humidity and temperature, respectively. The most abundant airborne bacteria (in units of CFU m−3) were: Staphylococcus sp. (72.4) > Micrococcus sp. (52.2) > Bacillus sp. (30.3) > Enterococcus sp. (24.0) > Serratia marcescens (20.1) > E. coli (19.1) > Pseudomonas sp. (16.0) > Nocardia …
Suppressing Bias Stress Degradation In High Performance Solution Processed Organic Transistors Operating In Air, Hamna F. Iqbal, Qianxiang Ai, Karl J. Thorley, Hu Chen, Iain Mcculloch, Chad Risko, John E. Anthony, Oana D. Jurchescu
Suppressing Bias Stress Degradation In High Performance Solution Processed Organic Transistors Operating In Air, Hamna F. Iqbal, Qianxiang Ai, Karl J. Thorley, Hu Chen, Iain Mcculloch, Chad Risko, John E. Anthony, Oana D. Jurchescu
Chemistry Faculty Publications
Solution processed organic field effect transistors can become ubiquitous in flexible optoelectronics. While progress in material and device design has been astonishing, low environmental and operational stabilities remain longstanding problems obstructing their immediate deployment in real world applications. Here, we introduce a strategy to identify the most probable and severe degradation pathways in organic transistors and then implement a method to eliminate the main sources of instabilities. Real time monitoring of the energetic distribution and transformation of electronic trap states during device operation, in conjunction with simulations, revealed the nature of traps responsible for performance degradation. With this information, we …
N-Type Charge Transport In Heavily P-Doped Polymers, Zhiming Liang, Hyun Ho Choi, Xuyi Luo, Tuo Liu, Ashkan Abtahi, Uma Shantini Ramasamy, J. Andrew Hitron, Kyle N. Baustert, Jacob L. Hempel, Alex M. Boehm, Armin Ansary, Douglas R. Strachan, Jianguo Mei, Chad Risko, Vitaly Podzorov, Kenneth R. Graham
N-Type Charge Transport In Heavily P-Doped Polymers, Zhiming Liang, Hyun Ho Choi, Xuyi Luo, Tuo Liu, Ashkan Abtahi, Uma Shantini Ramasamy, J. Andrew Hitron, Kyle N. Baustert, Jacob L. Hempel, Alex M. Boehm, Armin Ansary, Douglas R. Strachan, Jianguo Mei, Chad Risko, Vitaly Podzorov, Kenneth R. Graham
Chemistry Faculty Publications
It is commonly assumed that charge-carrier transport in doped π-conjugated polymers is dominated by one type of charge carrier, either holes or electrons, as determined by the chemistry of the dopant. Here, through Seebeck coefficient and Hall effect measurements, we show that mobile electrons contribute substantially to charge-carrier transport in π-conjugated polymers that are heavily p-doped with strong electron acceptors. Specifically, the Seebeck coefficient of several p-doped polymers changes sign from positive to negative as the concentration of the oxidizing agents FeCl3 or NOBF4 increase, and Hall effect measurements for the same p-doped polymers reveal that …
Application Of A Small Unmanned Aerial System To Measure Ammonia Emissions From A Pilot Amine-Co2 Capture System, Travis J. Schuyler, Bradley Irvin, Keemia Abad, Jesse G. Thompson, Kunlei Liu, Marcelo I. Guzman
Application Of A Small Unmanned Aerial System To Measure Ammonia Emissions From A Pilot Amine-Co2 Capture System, Travis J. Schuyler, Bradley Irvin, Keemia Abad, Jesse G. Thompson, Kunlei Liu, Marcelo I. Guzman
Chemistry Faculty Publications
The quantification of atmospheric gases with small unmanned aerial systems (sUAS) is expanding the ability to safely perform environmental monitoring tasks and quickly evaluate the impact of technologies. In this work, a calibrated sUAS is used to quantify the emissions of ammonia (NH3) gas from the exit stack a 0.1 MWth pilot-scale carbon capture system (CCS) employing a 5 M monoethanolamine (MEA) solvent to scrub CO2 from coal combustion flue gas. A comparison of the results using the sUAS against the ion chromatography technique with the EPA CTM-027 method for the standard emission sampling of NH3 …
Atmospheric Measurements With Unmanned Aerial Systems (Uas), Marcelo I. Guzman
Atmospheric Measurements With Unmanned Aerial Systems (Uas), Marcelo I. Guzman
Chemistry Faculty Publications
This Special Issue provides the first literature collection focused on the development and implementation of unmanned aircraft systems (UAS) and their integration with sensors for atmospheric measurements on Earth. The research covered in the Special Issue combines chemical, physical, and meteorological measurements performed in field campaigns as well as conceptual and laboratory work. Useful examples for the development of platforms and autonomous systems for environmental studies are provided, which demonstrate how careful the operation of sensors aboard UAS must be to gather information for remote sensing in the atmosphere. The work serves as a key collection of articles to introduce …
Plasma And Serum Proteins Bound To Nanoceria: Insights Into Pathways By Which Nanoceria May Exert Its Beneficial And Deleterious Effects In Vivo, D. Allan Butterfield, Binghui Wang, Peng Wu, Sarita S. Hardas, Jason M. Unrine, Eric A. Grulke, Jian Cai, Jon B. Klein, William M. Pierce, Robert A. Yokel, Rukhsana Sultana
Plasma And Serum Proteins Bound To Nanoceria: Insights Into Pathways By Which Nanoceria May Exert Its Beneficial And Deleterious Effects In Vivo, D. Allan Butterfield, Binghui Wang, Peng Wu, Sarita S. Hardas, Jason M. Unrine, Eric A. Grulke, Jian Cai, Jon B. Klein, William M. Pierce, Robert A. Yokel, Rukhsana Sultana
Chemistry Faculty Publications
Nanoceria (CeO2, cerium oxide nanoparticles) is proposed as a therapeutic for multiple disorders. In blood, nanoceria becomes protein-coated, changing its surface properties to yield a different presentation to cells. There is little information on the interaction of nanoceria with blood proteins. The current study is the first to report the proteomics identification of plasma and serum proteins adsorbed to nanoceria. The results identify a number of plasma and serum proteins interacting with nanoceria, proteins whose normal activities regulate numerous cell functions: antioxidant/detoxification, energy regulation, lipoproteins, signaling, complement, immune function, coagulation, iron homeostasis, proteolysis, inflammation, protein folding, protease inhibition, adhesion, protein/RNA …
Computationally Aided Design Of A High-Performance Organic Semiconductor: The Development Of A Universal Crystal Engineering Core, Anthony J. Petty Ii, Qianxiang Ai, Jeni C. Sorli, Hamna F. Haneef, Geoffrey E. Purdum, Alex M. Boehm, Devin B. Granger, Kaichen Gu, Carla Patricia Lacerda Rubinger, Sean R. Parkin, Kenneth R. Graham, Oana D. Jurchescu, Yueh-Lin Loo, Chad Risko, John E. Anthony
Computationally Aided Design Of A High-Performance Organic Semiconductor: The Development Of A Universal Crystal Engineering Core, Anthony J. Petty Ii, Qianxiang Ai, Jeni C. Sorli, Hamna F. Haneef, Geoffrey E. Purdum, Alex M. Boehm, Devin B. Granger, Kaichen Gu, Carla Patricia Lacerda Rubinger, Sean R. Parkin, Kenneth R. Graham, Oana D. Jurchescu, Yueh-Lin Loo, Chad Risko, John E. Anthony
Chemistry Faculty Publications
Herein, we describe the design and synthesis of a suite of molecules based on a benzodithiophene “universal crystal engineering core”. After computationally screening derivatives, a trialkylsilylethyne-based crystal engineering strategy was employed to tailor the crystal packing for use as the active material in an organic field-effect transistor. Electronic structure calculations were undertaken to reveal derivatives that exhibit exceptional potential for high-efficiency hole transport. The promising theoretical properties are reflected in the preliminary device results, with the computationally optimized material showing simple solution processing, enhanced stability, and a maximum hole mobility of 1.6 cm2 V−1 s−1.
Triperyleno[3,3,3]Propellane Triimides: Achieving A New Generation Of Quasi-D3h Symmetric Nanostructures In Organic Electronics, Lingling Lv, Josiah Roberts, Chengyi Xiao, Zhenmei Jia, Wei Jiang, Chad Risko, Lei Zhang
Triperyleno[3,3,3]Propellane Triimides: Achieving A New Generation Of Quasi-D3h Symmetric Nanostructures In Organic Electronics, Lingling Lv, Josiah Roberts, Chengyi Xiao, Zhenmei Jia, Wei Jiang, Chad Risko, Lei Zhang
Chemistry Faculty Publications
Rigid three-dimensional (3D) polycyclic aromatic hydrocarbons (PAHs), in particular 3D nanographenes, have garnered interest due to their potential use in semiconductor applications and as models to study through-bond and through-space electronic interactions. Herein we report the development of a novel 3D-symmetric rylene imide building block, triperyleno[3,3,3]propellane triimides (6), that possesses three perylene monoimide subunits fused on a propellane. This building block shows several promising characteristics, including high solubility, large π-surfaces, electron-accepting capabilities, and a variety of reactive sites. Further, the building block is compatible with different reactions to readily yield quasi-D3h symmetric nanostructures (9, …
Using A Balloon-Launched Unmanned Glider To Validate Real-Time Wrf Modeling, Travis J. Schuyler, S. M. Iman Gohari, Gary Pundsack, Donald Berchoff, Marcelo I. Guzman
Using A Balloon-Launched Unmanned Glider To Validate Real-Time Wrf Modeling, Travis J. Schuyler, S. M. Iman Gohari, Gary Pundsack, Donald Berchoff, Marcelo I. Guzman
Chemistry Faculty Publications
The use of small unmanned aerial systems (sUAS) for meteorological measurements has expanded significantly in recent years. SUAS are efficient platforms for collecting data with high resolution in both space and time, providing opportunities for enhanced atmospheric sampling. Furthermore, advances in mesoscale weather research and forecasting (WRF) modeling and graphical processing unit (GPU) computing have enabled high resolution weather modeling. In this manuscript, a balloon-launched unmanned glider, complete with a suite of sensors to measure atmospheric temperature, pressure, and relative humidity, is deployed for validation of real-time weather models. This work demonstrates the usefulness of sUAS for validating and improving …
The Effects Of Reactant Concentration And Air Flow Rate In The Consumption Of Dissolved O2 During The Photochemistry Of Aqueous Pyruvic Acid, Alexis J. Eugene, Marcelo I. Guzman
The Effects Of Reactant Concentration And Air Flow Rate In The Consumption Of Dissolved O2 During The Photochemistry Of Aqueous Pyruvic Acid, Alexis J. Eugene, Marcelo I. Guzman
Chemistry Faculty Publications
The sunlight photochemistry of the organic chromophore pyruvic acid (PA) in water generates ketyl and acetyl radicals that contribute to the production and processing of atmospheric aerosols. The photochemical mechanism is highly sensitive to dissolved oxygen content, [O2(aq)], among other environmental conditions. Thus, herein we investigate the photolysis (λ ≥ 305 nm) of 10–200 mM PA at pH 1.0 in water covering the relevant range 0 ≤ [O2(aq)] ≤ 1.3 mM. The rapid consumption of dissolved oxygen by the intermediate photolytic radicals is monitored in real time with a dissolved oxygen electrode. …
A Simple And Robust Approach To Reducing Contact Resistance In Organic Transistors, Zachary A. Lamport, Katrina J. Barth, Hyunsu Lee, Eliot Gann, Sebastian Engmann, Hu Chen, Martin Guthold, Iain Mcculloch, John E. Anthony, Lee J. Richter, Dean M. Delongchamp, Oana D. Jurchescu
A Simple And Robust Approach To Reducing Contact Resistance In Organic Transistors, Zachary A. Lamport, Katrina J. Barth, Hyunsu Lee, Eliot Gann, Sebastian Engmann, Hu Chen, Martin Guthold, Iain Mcculloch, John E. Anthony, Lee J. Richter, Dean M. Delongchamp, Oana D. Jurchescu
Chemistry Faculty Publications
Efficient injection of charge carriers from the contacts into the semiconductor layer is crucial for achieving high-performance organic devices. The potential drop necessary to accomplish this process yields a resistance associated with the contacts, namely the contact resistance. A large contact resistance can limit the operation of devices and even lead to inaccuracies in the extraction of the device parameters. Here, we demonstrate a simple and efficient strategy for reducing the contact resistance in organic thin-film transistors by more than an order of magnitude by creating high work function domains at the surface of the injecting electrodes to promote channels …
Magnetic Ordering In A Vanadium-Organic Coordination Polymer Using A Pyrrolo[2,3-D:5,4-D']Bis(Thiazole)-Based Ligand, Yulia A. Getmanenko, Christopher S. Mullins, Vladimir N. Nesterov, Stephanie Lake, Chad Risko, Ezekiel Johnston-Halperin
Magnetic Ordering In A Vanadium-Organic Coordination Polymer Using A Pyrrolo[2,3-D:5,4-D']Bis(Thiazole)-Based Ligand, Yulia A. Getmanenko, Christopher S. Mullins, Vladimir N. Nesterov, Stephanie Lake, Chad Risko, Ezekiel Johnston-Halperin
Chemistry Faculty Publications
Here we present the synthesis and characterization of a hybrid vanadium-organic coordination polymer with robust magnetic order, a Curie temperature TC of ∼110 K, a coercive field of ∼5 Oe at 5 K, and a maximum mass magnetization of about half that of the benchmark ferrimagnetic vanadium(tetracyanoethylene)~2 (V·(TCNE)~2). This material was prepared using a new tetracyano-substituted quinoidal organic small molecule 7 based on a tricyclic heterocycle 4-hexyl-4H-pyrrolo[2,3-d:5,4-d′]bis(thiazole) (C6-PBTz). Single crystal X-ray diffraction of the 2,6-diiodo derivative of the parent C6-PBTz, showed a disordered hexyl chain and …
Photocatalytic Activity: Experimental Features To Report In Heterogeneous Photocatalysis, Md. Ariful Hoque, Marcelo I. Guzman
Photocatalytic Activity: Experimental Features To Report In Heterogeneous Photocatalysis, Md. Ariful Hoque, Marcelo I. Guzman
Chemistry Faculty Publications
Heterogeneous photocatalysis is a prominent area of research with major applications in solar energy conversion, air pollution mitigation, and removal of contaminants from water. A large number of scientific papers related to the photocatalysis field and its environmental applications are published in different journals specializing in materials and nanomaterials. However, many problems exist in the conception of papers by authors unfamiliar with standard characterization methods of photocatalysts as well as with the procedures needed to determine photocatalytic activities based on the determination of “apparent quantum efficiencies” within a wavelength interval or “apparent quantum yields” in the case of using monochromatic …
Gold-Catalyzed Conversion Of Lignin To Low Molecular Weight Aromatics, Yang Song, Justin K. Mobley, Ali Hussain Motagamwala, Mark Isaacs, James E. Dumesic, John Ralph, Adam F. Lee, Karen Wilson, Mark Crocker
Gold-Catalyzed Conversion Of Lignin To Low Molecular Weight Aromatics, Yang Song, Justin K. Mobley, Ali Hussain Motagamwala, Mark Isaacs, James E. Dumesic, John Ralph, Adam F. Lee, Karen Wilson, Mark Crocker
Chemistry Faculty Publications
A heterogeneous catalyst system, employing Au nanoparticles (NPs) and Li–Al (1 : 2) layered double hydroxide (LDH) as support, showed excellent activity in aerobic oxidation of the benzylic alcohol group in β-O-4 linked lignin model dimers to the corresponding carbonyl products using molecular oxygen under atmospheric pressure. The synergistic effect between Au NPs and the basic Li–Al LDH support induces further reaction of the oxidized model compounds, facilitating facile cleavage of the β-O-4 linkage. Extension to oxidation of γ-valerolactone (GVL) extracted lignin and kraft lignin using Au/Li–Al LDH under similar conditions produced a range of aromatic monomers in high yield. …
Cross Photoreaction Of Glyoxylic And Pyruvic Acids In Model Aqueous Aerosol, Sha-Sha Xia, Alexis J. Eugene, Marcelo I. Guzman
Cross Photoreaction Of Glyoxylic And Pyruvic Acids In Model Aqueous Aerosol, Sha-Sha Xia, Alexis J. Eugene, Marcelo I. Guzman
Chemistry Faculty Publications
Aerosols of variable composition, size, and shape are associated with public health concerns as well as with light-particle interactions that play a role in the energy balance of the atmosphere. Photochemical reactions of 2-oxocarboxylic acids in the aqueous phase are now known to contribute to the total secondary organic aerosol (SOA) budget. This work explores the cross reaction of glyoxylic acid (GA) and pyruvic acid (PA) in water, the two most abundant 2-oxocarboxylic acids in the atmosphere, under solar irradiation and dark thermal aging steps. During irradiation, PA and GA are excited and initiate proton-coupled electron transfer or hydrogen abstraction …
Oxidation Of N-Doped Multiwalled Carbon Nanotubes And Formation Of Discontinuous Spiraled Carbon Nanoribbons, Aman Preet Kaur, Mark S. Meier, Rodney Andrews, Dali Qian
Oxidation Of N-Doped Multiwalled Carbon Nanotubes And Formation Of Discontinuous Spiraled Carbon Nanoribbons, Aman Preet Kaur, Mark S. Meier, Rodney Andrews, Dali Qian
Chemistry Faculty Publications
The effects of five commonly used wet chemical oxidations were studied for the extent of oxidation of graphitized nitrogen-doped multiwalled carbon nanotubes (N-MWCNTs). KMnO4/ H2SO4 was the most potent oxidant, as it produced the highest fraction of oxygen-containing functional groups. Electron microscopy studies showed that the treatment of annealed N-MWCNTs (G-N-MWCNTs) with H2SO4/HNO3 and H2SO4/KMnO4 mixtures leads to interesting spiraled ribbon textures. A structural model, involving the stacking of coiled subunits to form a discontinuous carbon nanoribbon rather than a continuous ribbon is proposed to …
Dynamics Of Singlet Fission And Electron Injection In Self-Assembled Acene Monolayers On Titanium Dioxide, Natalie A. Pace, Dylan H. Arias, Devin B. Granger, Steven Christensen, John E. Anthony, Justin C. Johnson
Dynamics Of Singlet Fission And Electron Injection In Self-Assembled Acene Monolayers On Titanium Dioxide, Natalie A. Pace, Dylan H. Arias, Devin B. Granger, Steven Christensen, John E. Anthony, Justin C. Johnson
Chemistry Faculty Publications
We employ a combination of linear spectroscopy, electrochemistry, and transient absorption spectroscopy to characterize the interplay between electron transfer and singlet fission dynamics in polyacene-based dyes attached to nanostructured TiO2. For triisopropyl silylethynyl (TIPS)-pentacene, we find that the singlet fission time constant increases to 6.5 ps on a nanostructured TiO2 surface relative to a thin film time constant of 150 fs, and that triplets do not dissociate after they are formed. In contrast, TIPS-tetracene singlets quickly dissociate in 2 ps at the molecule/TiO2 interface, and this dissociation outcompetes the relatively slow singlet fission process. The addition …
Preventing Crossover In Redox Flow Batteries Through Active Material Oligomerization, Susan A. Odom
Preventing Crossover In Redox Flow Batteries Through Active Material Oligomerization, Susan A. Odom
Chemistry Faculty Publications
No abstract provided.
Effect Of Molecular Side Groups And Local Nanoenvironment On Photodegradation And Its Reversibility, Nicole Quist, Mark Li, Ryan Tollefsen, Michael Haley, John Anthony, Oksana Ostroverkhova
Effect Of Molecular Side Groups And Local Nanoenvironment On Photodegradation And Its Reversibility, Nicole Quist, Mark Li, Ryan Tollefsen, Michael Haley, John Anthony, Oksana Ostroverkhova
Chemistry Faculty Publications
Degradation of organic semiconductors in the presence of oxygen is one of the bottlenecks preventing their wide-spread use in optoelectronic devices. The first step towards such degradation in functionalized pentacene (Pn) derivatives is formation of endoperoxide (EPO), which can either revert back to the parent molecule or proceed to molecule decomposition. We present the study of reversibility of EPO formation through probing the photophysical properties of functionalized fluorinated pentacene (Pn-R-F8) derivatives. Experiments are done in solutions and in films both at the single molecule level and in the bulk. In solutions, degradation of optical absorption and its partial recovery after …
Unmanned Aerial Systems For Monitoring Trace Tropospheric Gases, Travis J. Schuyler, Marcelo I. Guzman
Unmanned Aerial Systems For Monitoring Trace Tropospheric Gases, Travis J. Schuyler, Marcelo I. Guzman
Chemistry Faculty Publications
The emission of greenhouse gases (GHGs) has changed the composition of the atmosphere during the Anthropocene. Accurately documenting the sources and magnitude of GHGs emission is an important undertaking for discriminating the contributions of different processes to radiative forcing. Currently there is no mobile platform that is able to quantify trace gases at altitudes(UASs) can be deployed on-site in minutes and can support the payloads necessary to quantify trace gases. Therefore, current efforts combine the use of UASs available on the civilian market with inexpensively designed analytical systems for monitoring atmospheric trace gases. In this context, this perspective introduces the …
Real-Time Sensing Of Single-Ligand Delivery With Nanoaperture-Integrated Microfluidic Devices, W. Elliott Martin, Ning Ge, Bernadeta R. Srijanto, Emily Furnish, C. Patrick Collier, Christine A. Trinkle, Christopher I. Richards
Real-Time Sensing Of Single-Ligand Delivery With Nanoaperture-Integrated Microfluidic Devices, W. Elliott Martin, Ning Ge, Bernadeta R. Srijanto, Emily Furnish, C. Patrick Collier, Christine A. Trinkle, Christopher I. Richards
Chemistry Faculty Publications
The measurement of biological events on the surface of live cells at the single-molecule level is complicated by several factors including high protein densities that are incompatible with single-molecule imaging, cellular autofluorescence, and protein mobility on the cell surface. Here, we fabricated a device composed of an array of nanoscale apertures coupled with a microfluidic delivery system to quantify single-ligand interactions with proteins on the cell surface. We cultured live cells directly on the device and isolated individual epidermal growth factor receptors (EGFRs) in the apertures while delivering fluorescently labeled epidermal growth factor. We observed single ligands binding to EGFRs, …
Real-Time Atomistic Observation Of Structural Phase Transformations In Individual Hafnia Nanorods, Bethany M. Hudak, Sean W. Depner, Gregory R. Waetzig, Anjana Talapatra, Raymundo Arroyave, Sarbajit Banerjee, Beth S. Guiton
Real-Time Atomistic Observation Of Structural Phase Transformations In Individual Hafnia Nanorods, Bethany M. Hudak, Sean W. Depner, Gregory R. Waetzig, Anjana Talapatra, Raymundo Arroyave, Sarbajit Banerjee, Beth S. Guiton
Chemistry Faculty Publications
High-temperature phases of hafnium dioxide have exceptionally high dielectric constants and large bandgaps, but quenching them to room temperature remains a challenge. Scaling the bulk form to nanocrystals, while successful in stabilizing the tetragonal phase of isomorphous ZrO2, has produced nanorods with a twinned version of the room temperature monoclinic phase in HfO2. Here we use in situ heating in a scanning transmission electron microscope to observe the transformation of an HfO2 nanorod from monoclinic to tetragonal, with a transformation temperature suppressed by over 1000°C from bulk. When the nanorod is annealed, we observe with …
Oxidation Of Substituted Catechols At The Air-Water Interface: Production Of Carboxylic Acids, Quinones, And Polyphenols, Elizabeth A. Pillar, Marcelo I. Guzman
Oxidation Of Substituted Catechols At The Air-Water Interface: Production Of Carboxylic Acids, Quinones, And Polyphenols, Elizabeth A. Pillar, Marcelo I. Guzman
Chemistry Faculty Publications
Anthropogenic activities contribute benzene, toluene, and anisole to the environment, which in the atmosphere are converted into the respective phenols, cresols, and methoxyphenols by fast gas-phase reaction with hydroxyl radicals (HO(•)). Further processing of the latter species by HO(•) decreases their vapor pressure as a second hydroxyl group is incorporated to accelerate their oxidative aging at interfaces and in aqueous particles. This work shows how catechol, pyrogallol, 3-methylcatechol, 4-methylcatechol, and 3-methoxycatechol (all proxies for oxygenated aromatics derived from benzene, toluene, and anisole) react at the air-water interface with increasing O3(g) during τc ≈ 1 μs contact time and contrasts their …
Catalyzed Synthesis Of Zinc Clays By Prebiotic Central Metabolites, Marcelo I. Guzman, Ruixin Zhou, Kaustuv Basu, Hyman Hartman, Christopher J. Matocha, S. Kelly Sears, Hajatollah Vali
Catalyzed Synthesis Of Zinc Clays By Prebiotic Central Metabolites, Marcelo I. Guzman, Ruixin Zhou, Kaustuv Basu, Hyman Hartman, Christopher J. Matocha, S. Kelly Sears, Hajatollah Vali
Chemistry Faculty Publications
How primordial metabolic networks such as the reverse tricarboxylic acid (rTCA) cycle and clay mineral catalysts coevolved remains a mystery in the puzzle to understand the origin of life. While prebiotic reactions from the rTCA cycle were accomplished via photochemistry on semiconductor minerals, the synthesis of clays was demonstrated at low temperature and ambient pressure catalyzed by oxalate. Herein, the crystallization of clay minerals is catalyzed by succinate, an example of a photoproduced intermediate from central metabolism. The experiments connect the synthesis of sauconite, a model for clay minerals, to prebiotic photochemistry. We report the temperature, pH, and concentration dependence …
Single Molecule-Level Study Of Donor-Acceptor Interactions And Nanoscale Environment In Blends, Nicole Quist, Rebecca Grollman, Jeremy Rath, Alex Robertson, Michael Haley, John E. Anthony, Oksana Ostroverkhova
Single Molecule-Level Study Of Donor-Acceptor Interactions And Nanoscale Environment In Blends, Nicole Quist, Rebecca Grollman, Jeremy Rath, Alex Robertson, Michael Haley, John E. Anthony, Oksana Ostroverkhova
Chemistry Faculty Publications
Organic semiconductors have attracted considerable attention due to their applications in low-cost (opto)electronic devices. The most successful organic materials for applications that rely on charge carrier generation, such as solar cells, utilize blends of several types of molecules. In blends, the local environment strongly influences exciton and charge carrier dynamics. However, relationship between nanoscale features and photophysics is difficult to establish due to the lack of necessary spatial resolution. We use functionalized fluorinated pentacene (Pn) molecule as single molecule probes of intermolecular interactions and of the nanoscale environment in blends containing donor and acceptor molecules. Single Pn donor (D) molecules …
Nitrate Radicals And Biogenic Volatile Organic Compounds: Oxidation, Mechanisms And Organic Aerosol, Nga Lee Ng, Steven S. Brown, Alexander T. Archibald, Elliot Atlas, Ronald C. Cohen, John N. Crowley, Douglas A. Day, Neil M. Donahue, Juliane L. Fry, Hendrik Fuchs, Robert J. Griffin, Marcelo I. Guzman, Hartmut Hermann, Alma Hodzic, Yoshiteru Iinuma, José L. Jimenez, Astrid Kiendler-Scharr, Ben H. Lee, Deborah J. Luecken, Jingqiu Mao, Robert Mclaren, Anke Mutzel, Hans D. Osthoff, Bin Ouyang, Benedicte Picquet-Varrault, Ulrich Platt, Havala O. T. Pye, Yinon Rudich, Rebecca H. Schwantes, Manabu Shiraiwa, Jochen Stutz, Joel A. Thornton, Andreas Tilgner, Brent J. Williams, Rahul A. Zaveri
Nitrate Radicals And Biogenic Volatile Organic Compounds: Oxidation, Mechanisms And Organic Aerosol, Nga Lee Ng, Steven S. Brown, Alexander T. Archibald, Elliot Atlas, Ronald C. Cohen, John N. Crowley, Douglas A. Day, Neil M. Donahue, Juliane L. Fry, Hendrik Fuchs, Robert J. Griffin, Marcelo I. Guzman, Hartmut Hermann, Alma Hodzic, Yoshiteru Iinuma, José L. Jimenez, Astrid Kiendler-Scharr, Ben H. Lee, Deborah J. Luecken, Jingqiu Mao, Robert Mclaren, Anke Mutzel, Hans D. Osthoff, Bin Ouyang, Benedicte Picquet-Varrault, Ulrich Platt, Havala O. T. Pye, Yinon Rudich, Rebecca H. Schwantes, Manabu Shiraiwa, Jochen Stutz, Joel A. Thornton, Andreas Tilgner, Brent J. Williams, Rahul A. Zaveri
Chemistry Faculty Publications
Oxidation of biogenic volatile organic compounds (BVOC) by the nitrate radical (NO3) represents one of the important interactions between anthropogenic emissions related to combustion and natural emissions from the biosphere. This interaction has been recognized for more than 3 decades, during which time a large body of research has emerged from laboratory, field, and modeling studies. NO3-BVOC reactions influence air quality, climate and visibility through regional and global budgets for reactive nitrogen (particularly organic nitrates), ozone, and organic aerosol. Despite its long history of research and the significance of this topic in atmospheric chemistry, a number …
Spray Printing Of Organic Semiconducting Single Crystals, Grigorios-Panagiotis Rigas, Marcia M. Payne, John E. Anthony, Peter N. Horton, Fernando A. Castro, Maxim Shkunov
Spray Printing Of Organic Semiconducting Single Crystals, Grigorios-Panagiotis Rigas, Marcia M. Payne, John E. Anthony, Peter N. Horton, Fernando A. Castro, Maxim Shkunov
Chemistry Faculty Publications
Single-crystal semiconductors have been at the forefront of scientific interest for more than 70 years, serving as the backbone of electronic devices. Inorganic single crystals are typically grown from a melt using time-consuming and energy-intensive processes. Organic semiconductor single crystals, however, can be grown using solution-based methods at room temperature in air, opening up the possibility of large-scale production of inexpensive electronics targeting applications ranging from field-effect transistors and light-emitting diodes to medical X-ray detectors. Here we demonstrate a low-cost, scalable spray-printing process to fabricate high-quality organic single crystals, based on various semiconducting small molecules on virtually any substrate by …
Grain Boundary Induced Bias Instability In Soluble Acene-Based Thin-Film Transistors, Ky V. Nguyen, Marcia M. Payne, John E. Anthony, Jung Hun Lee, Eunjoo Song, Boseok Kang, Kilwon Cho, Wi Hyoung Lee
Grain Boundary Induced Bias Instability In Soluble Acene-Based Thin-Film Transistors, Ky V. Nguyen, Marcia M. Payne, John E. Anthony, Jung Hun Lee, Eunjoo Song, Boseok Kang, Kilwon Cho, Wi Hyoung Lee
Chemistry Faculty Publications
Since the grain boundaries (GBs) within the semiconductor layer of organic field-effect transistors (OFETs) have a strong influence on device performance, a substantial number of studies have been devoted to controlling the crystallization characteristics of organic semiconductors. We studied the intrinsic effects of GBs within 5,11-bis(triethylsilylethynyl) anthradithiophene (TES-ADT) thin films on the electrical properties of OFETs. The GB density was easily changed by controlling nulceation event in TES-ADT thin films. When the mixing time was increased, the number of aggregates in as-spun TES-ADT thin films were increased and subsequent exposure of the films to 1,2-dichloroethane vapor led to a significant …
Aqueous Photochemistry Of Glyoxylic Acid, Alexis J. Eugene, Sha-Sha Xia, Marcelo I. Guzman
Aqueous Photochemistry Of Glyoxylic Acid, Alexis J. Eugene, Sha-Sha Xia, Marcelo I. Guzman
Chemistry Faculty Publications
Aerosols affect climate change, the energy balance of the atmosphere, and public health due to their variable chemical composition, size, and shape. While the formation of secondary organic aerosols (SOA) from gas phase precursors is relatively well understood, studying aqueous chemical reactions contributing to the total SOA budget is the current focus of major attention. Field measurements have revealed that mono-, di-, and oxo-carboxylic acids are abundant species present in SOA and atmospheric waters. This work explores the fate of one of these 2-oxocarboxylic acids, glyoxylic acid, which can photogenerate reactive species under solar irradiation. Additionally, the dark thermal aging …
Strain Effects On The Work Function Of An Organic Semiconductor, Yanfei Wu, Annabel R. Chew, Geoffrey A. Rojas, Gjergji Sini, Greg Haugstad, Alex Belianinov, Sergei V. Kalinin, Hong Li, Chad Risko, Jean-Luc Brédas, Alberto Salleo, C. Daniel Frisbie
Strain Effects On The Work Function Of An Organic Semiconductor, Yanfei Wu, Annabel R. Chew, Geoffrey A. Rojas, Gjergji Sini, Greg Haugstad, Alex Belianinov, Sergei V. Kalinin, Hong Li, Chad Risko, Jean-Luc Brédas, Alberto Salleo, C. Daniel Frisbie
Chemistry Faculty Publications
Establishing fundamental relationships between strain and work function (WF) in organic semiconductors is important not only for understanding electrical properties of organic thin films, which are subject to both intrinsic and extrinsic strains, but also for developing flexible electronic devices. Here we investigate tensile and compressive strain effects on the WF of rubrene single crystals. Mechanical strain induced by thermal expansion mismatch between the substrate and rubrene is quantified by X-ray diffraction. The corresponding WF change is measured by scanning Kelvin probe microscopy. The WF of rubrene increases (decreases) significantly with in-plane tensile (compressive) strain, which agrees qualitatively with density …