Spectroscopy/Diffraction Related User Projects

• Signature Discovery in Organic Compounds
  Project Lead: John Cort
  Project Lead Institution: Pacific Northwest National Laboratory
  Abstract
  This project will survey physical and chemical characteristics of organic compounds of interest in chemical forensics applications.The goal is to develop chemical attribution signatures (CAS’s) for source attribution and sample matching. Chemical forensics is a discipline whose central goal is attribution or matching of a chemical compound to its source, origin, or to other samples. Using NMR spectroscopy, chromatography, mass spectrometry, UV-Vis spectroscopy, and other techniques, we are identifying and characterizing novel physical and chemical attribution signatures.
• XPS Surface Analysis of Metal Coupons
  Project Lead: Jerome Birnbaum
  Project Lead Institution: Pacific Northwest National Laboratory
  Abstract
  A series of metal coupons will undergo heat treatments under varying conditons in a separate PNNL laboratory from EMSL. Following the treatment the coupons will be delivered to Mark Engelhard to conduct XPS analysis. Of most interest is the presence of and the quantity of carbon on the surface of the coupons. Also of high interest will be the presence of any other species formed on the surface of the coupons.
• Analysis of metals deposited on silica particles
  Project Lead: George Hager
  Project Lead Institution: Pacific Northwest National Laboratory
  Abstract
  Our research will be directed at examining metal layers deposited on three distinct silica particles by tow unique methods by both ToF-SIMS and XPS
• The Effects of Radiation Damage on Heteroepitaxial Interfaces
  Project Lead: Richard Kurtz
  Project Lead Institution: Pacific Northwest National Laboratory
  Abstract
  The interaction of radiation with materials controls the performance, reliability, and safety of conventional and advanced nuclear power systems. Energetic particles produced by nuclear reactions displace atoms in surrounding materials from their lattice sites, resulting in high local temperatures and formation of vacancies and interstitials that are deleterious to important material properties. Recent research suggests that nanospaced internal interfaces are powerful sinks for vacancies and interstitials [1-3]. Revolutionary improvements in radiation tolerance may be attainable if methods can be found to manipulate interface structures at the nanoscale to tailor their properties for optimal interface stability and point defect recombination, and to serve as traps for gaseous transmutants such as helium and hydrogen [4-6]. Interfaces contain miscoordinated atoms and excess volume that can assist recombination processes. A high-density of nanoscale features will dramatically increase interface area and shorten the diffusion path for defect recombination. Although recent experiments and modeling demonstrate the efficacy of this concept [7-9], the exact roles of interface free volume and the specific type of interface are not well understood. More importantly, an accurate physical description of point defect absorption and recombination processes occurring at interfaces does not exist. We propose to perform carefully controlled experiments utilizing well-characterized model interfaces to elucidate the fundamental mechanisms governing defect absorption and recombination at interfaces. The key scientific objectives of this research are 1) to understand how interface character affects absorption and recombination of radiation-induced defects, 2) to determine the ability of interfaces to delocalize radiation-induced defects to promote recombination, and 3) to determine the stability and evolution of interfaces under irradiation to high doses.
• Imaging and Monitoring the Initial Stages of Biofilm Formation
  Project Lead: Raymond Addleman
  Project Lead Institution: Pacific Northwest National Laboratory
  Abstract
  As outlined below, the goal of this study to apply an integrated, multi-faceted approach to the analysis of the initial molecular and cellular processes involved with cell adhesion, colonization, and biofilm formation so as to gain near-nanometer scale resolution of surfaces, biomolecules, and cells exactly as they come together in situ. Specific objectives are to establish PNNL thought leadership and capabilities for techniques that: 1. Improve understanding of the sequential and spatial deposition of biomolecules onto fresh surfaces. 2. Image and monitor the impact that surface chemistry, nanostructure, and microstructure have upon formation of the biofilm and cell adhesion. 3. Identify how the composition and distribution of cellular adhesion, colony formation, and ultimately outgrowth and formation of a biofilm. 4. Establish an interdisciplinary, multiscale mechanistic understanding of biofilm formation. 5. Develop the capability to construct non-toxic multifunctional materials that retard, prevent, or promote biofouling and biofilm formation. Throughout the course of this project, the team will proroduce high-impact publications in the field of biofouling and the nano-biointerface that will demonostrate PNNL leadership and capabilities in biofilm formation and bifouling. In addition to publications, the new insights may lead to intellectual property, which will be protected as warranted.
• Use of synthetic biology to probe molecular machines in photosynthesis
  Project Lead: Himadri Pakrasi
  Project Lead Institution: Washington University in St. Louis
  Abstract
  We have shown in our previous EMSL collaborations our ability to develop systems-­level models of cyanobacterial processes. In the present proposal, our objective is to characterize and improve the molecular machines in photosynthesis that govern bioenergy production in cyanobacteria. This proposal results from an EMSL workshop (MBGC 2.0) held in spring 2011. We propose to apply sets of experiments and analysis to achieve this goal using sophisticated imaging instrumentation available at EMSL. The profound expertise of the External Project Team in the areas of cyanobacterial and systems biology will be leveraged to attain the goals under this objective. The PIs Pakrasi, Sherman and Aurora have had extensive experience in collaborating with key investigators at EMSL/PNNL over the past 5 years, resulting in numerous publications (8-­15, as examples). The experiments outlined in this proposal will strive to investigate the products of a synthetic biology approach targeted in the following important areas of cyanobacterial biology; the goal of each is designed to provide new approaches to increasing photosynthetic productivity: 1) Photoshynthetic antenna modification; 2) photosynthetic electron transport and photosystem stoichiometry; 3) topology of photosynthetic membranes; and 4) carboxysome design and CO2 fixation.
• Characterization of Catalyst Materials in the Electron and Atom Probe Microscopes
  Project Lead: Ilke Arslan
  Project Lead Institution: Pacific Northwest National Laboratory
  Abstract
  The overall goal of this proposal is to develop a fundamental understanding of how to predict, synthesize, and control the compositions, structures, and catalytic function of supported metal clusters possessing designed atomic connectivity and ligand environments. Specifically, the PI of this proposal aims to advance the existing characterization tools at PNNL by combining several key tools in the electron and atom-probe microscopes. For example, the combination of atomic-resolution images of single or small metal cluster catalysts with 3-D electron tomography of its porous zeolite support for a complete understanding of the system connecting length and dimension scales; the combination of ex-situ or in-situ gas reduction combined with 3-D imaging to determine the 3-D distribution and morphology of the catalysts within the support before and after reduction; or the combination of electron tomography (ET) with atom probe tomography (APT) at various stages of reduction, providing the new capability of understanding the 3-D morphology, distribution, and chemistry with atomic resolution and without artifacts (the artifacts can be removed through the 3-D correlation of the ET and APT data). Electron energy loss spectroscopy (EELS) will be a major part of each set of experiments as an understanding of the changes in bonding and electronic structure is imperative to a fundamental understanding of the system as a whole. Further, it is important to characterize the structures, intermediates, and catalytic reaction products at various stages of growth and design, so not only is it essential to combine the techniques, it is also necessary to examine the materials through a “time-lapse" of various stages of design.
• in Operando Characterization of Contact Catalysts at Mesoscale Distances
  Project Lead: Robert Weber
  Project Lead Institution: Pacific Northwest National Laboratory
  Abstract
  We propose to measure and model the dipole-dipole interactions that shift and quench luminescence spectra of ligand-to-metal charge transfer bands of contact catalysts containing transition metal in order to quantify inter-site geometries and the polarizability of the reaction medium within 1-10 nm of the active sites. The former is needed to refine the syntheses that lead to well defined catalysts and to track their evolution. The latter is needed to understand molecular transport to and from the catalyst surface. We will develop the use of luminescence lifetime spectroscopy to probe the composition and geometry in that regime under conditions that could be employed to characterize catalysts under reaction conditions.The work relies on expertise resident at EMSL (spectroscopy) and PNNL (synthesis, modeling) with EMSL’s advanced facilities for spectroscopy (femtosecond LIF) and quantum chemical modeling (NWChem, CP2k running on large scale, parallel computers).
• FRACKING OPTIMIZATION AND IN-SITU CHARACTERIZATION OF ROCK PERMEABILITY AND FRACTURE DISTRIBUTIONS
  Project Lead: Carlos Fernandez
  Project Lead Institution: Pacific Northwest National Laboratory
  Abstract
  Enhanced Geothermal Systems (EGS) are the future of geothermal energy, and geothermal is the future of energy production within the US and worldwide. However, to our knowledge, no prior EGS project has sustained production at rates greater than ½ of what is needed for economic viability. Tremendous amounts of fractured-rock surface area for heat exchange and volumes of fluid flow are needed to sustain EGS. The primary limitation that makes commercial EGS infeasible is our current inability to cost-effectively create high-permeability reservoirs from impermeable, igneous rock within the 3-10 km depth range. The oil and gas industry demonstrated that real-time control/adjustment of stimulation is critical. However, our understanding of stimulation in geothermal systems remains extremely limited. Development of permeability-enhancement technologies specifically for geothermal systems is required before EGS will become viable. This project will maximize the permeability enhancement while minimizing the cost of EGS reservoir stimulation through technology and monitoring method development enabling real-time optimization of permeability enhancement. Improving our stimulation methods decreases reservoir creation cost through increasing the well spacing and decreasing the number of wells needed. Improving stimulation implementation with real-time monitoring decreases cost through decreasing the need to repeat stimulation, which is currently used to mitigate unsuccessful stimulation or optimize stimulation. Novel physical and chemical methods will be employed to advance our ability to stimulate permeability within geothermal reservoirs.
• Fundamental Studies of Vehicle Emission Control Catalysts
  Project Lead: Charles Peden
  Project Lead Institution: Pacific Northwest National Laboratory
  Abstract
  The abatement of environmentally harmful NOx compounds (NO, NO2, and N2O) emitted from mobile or stationary power sources remains a challenging task for the catalysis community. In particular, conventional three-way catalysts used in the exhaust after treatment technologies of internal combustion engines prove ineffective when the engine is operated under highly oxidizing conditions (to achieve better fuel efficiency). The problem is daunting, since reduction chemistry (NOx to N2) has to be carried out under highly oxidizing conditions. Several approaches have been proposed for lean-NOx abatement, each of them with its own specific sets of problems. The two technologies that seem to have clear advantages among the processes proposed are the selective catalytic reduction either with hydrocarbons (HC-SCR) or with ammonia (NH3-SCR), and NOx storage reduction (NSR). For the NH3-SCR technology, transition metal (in particular Fe and Cu) ion-exchanged zeolite catalysts have shown high activity and N2 selectivity. NSR catalysts work under cyclic operation conditions: oxidation of NO to NO2 followed by storage as nitrates/nitrites on alkali or alkaline oxides under lean conditions, and subsequent reduction of the released NOx under rich conditions. To further advance these important exhaust emission technologies, we are carrying out several research programs, funded by DOE/Office of Energy Efficiency and Renewable Energy (EERE)/Vehicle Technologies Program (VT), involving both programs that include direct collaboration with industry partners (at GM, Ford and Cummins), and a more fundamental program. For all of these programs, we rely on the use of a wide array of state-of-the-art catalyst characterization facilities in the EMSL at PNNL.