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  1. Chemistry Department Colloquium

    "Electronic Cooperativity in Supported Single and Multinuclear-Sites for Catalytic C-C and C-H Bond Functionalization"

    Presented by Dr. Massimiliano Delferro, Argonne National Laboratory

    Monday, October 28, 2019, 11 am
    Hamilton Seminar Room, Bldg. 555

    Hosted by: Sanjaya Senanayake

    Systematic study of the interactions between organometallic catalysts and metal oxide support materials is essential for the realization of rational design in heterogeneous catalysis. In this talk, I will describe the stoichiometric and catalytic chemistry of a series of organometallic complex chemisorbed on a variety of metal oxides as a multifaceted probe for stereoelectronic communication between the support and organometallic center. Electrophilic bond activation was explored in the context of stoichiometric hydrogenolysis as well as catalytic hydrogenation, dehydrogenation, and H/D exchange. Strongly acidic modified metal oxides such as sulfated zirconia engender high levels of activity toward electrophilic bond activation of both sp2 and sp3 C–H bonds, including the rapid activation of methane at room temperature; however, the global trend for the supports studied here does not suggest a direct correlation between activity and surface Brønsted acidity, and more complex metal surface interactions are at play.

  2. NSLS-II Friday Lunchtime Seminar

    "Plant-fungal symbiosis and their potential impacts on terrestrial biogeochemistry"

    Presented by Ko-Hsuan (Koko) Chen, University of Florida

    Friday, October 25, 2019, 12 pm
    NSLS-II Bldg. 743 Room 156

    Hosted by: Ignace Jarrige

    Fungi are associated with all lineages of land plants. While plant-fungal symbiosis is common, many of their interactions, ranging from mutualism, commensalism, to parasitism are yet to be determined. As plant-fungal symbiosis are tightly linked to nutrient cycling, different interaction types have substantial impacts on biogeochemistry. Here, we will use two plant-fungal symbiosis examples: 1) Pine and their ectomycorrhizal fungi, and 2) mosses and their associated fungi, to illustrate how considering plant-fungal interaction and biogeochemistry together can further our understanding toward a better understanding of plant-fungal biology.

  3. Center for Functional Nanomaterials Seminar

    "Heterogeneous Chemistry at Liquid/Vapor Interfaces Investigated with Photoelectron Spectroscopy"

    Presented by Hendrik Bluhm, Fritz Haber Institute of the Max Planck Society, Department of Inorganic Chemistry, Faradayweg, Berlin, Germany

    Monday, October 21, 2019, 11 am
    Bldg.735 (CFN) 1st floor conference room

    Hosted by: Ashley Head

    Aqueous solution/vapor interfaces govern important phenomena in the environment and atmosphere, including the uptake and release of trace gases by aerosols and CO2 sequestration by the oceans.[1] A detailed understanding of these processes requires the investigation of liquid/vapor interfaces with chemical sensitivity and interface specificity under ambient conditions, i.e., temperatures above 200 K and water vapour pressures in the millibar to tens of millibar pressure range. This talk will discuss opportunities and challenges for investigations of liquid/vapor interfaces using X-ray photoelectron spectroscopy and describe some recent experiments that have focused on the propensity of certain ions and the role of surfactants at the liquid/vapor interface. [1] O. Björneholm et al., Chem. Rev. 116, 7698 (2016).

  4. Chemistry Department Seminar

    "Advancing Nanomaterials Research with In Situ TEM"

    Presented by Jordan Moering, Protochips, Inc. 3800 Gateway Centre Blvd, Morrisville NC, 27560

    Wednesday, October 9, 2019, 2 pm
    CFN, Bldg 735, Conference Room A

    Hosted by: Fernando Camino

    The advent of in situ thermal and electrical sample control within realistic environments has transformed the Transmission Electron Microscope (TEM) from a simple high-resolution image acquisition tool into a nanoscale materials research and development laboratory. For example, to support the growing need of photovoltaic and quantum materials researchers, the Fusion Select system couples precise pA-level electrical control with a friction-free tilting stage, allowing users to simultaneously characterize samples at high tilt and high temperature. Featuring a user-friendly software interface, a series of FIB-optimized sample supports, and extensive training material, the Fusion Select system is optimized for new users attempting their first in situ electrical or thermal TEM studies For environmental TEM analysis, the Catalysis Package for the Atmosphere System is the first commercial closed-cell system with an integrated mass spectrometer and flexible gas handling system specifically designed for catalyst materials research. Recognized as one of the top ten microscopy innovations of 2019, the Atmosphere system has been designed specifically for electron microscopy by maximizing gas mixing and pressure control while minimizing mechanical vibrations and new user learning curve. This talk will review these and other capabilities as they relate to the aims of the CFN – enabling external users to carry out high-impact nanoscience projects, while enhancing the in-house functional nanomaterial research conducted by staff scientists.

  5. Chemistry Department Colloquium

    "Coupling Molecular Catalysts with Light-Harvesting Surfaces for Solar CO2 Reduction"

    Presented by Gonghu Li, Dept. of Chemistry, University of New Hampshire

    Monday, October 7, 2019, 11 am
    Hamilton Seminar Room, Bldg. 555

    Hosted by: David Grills and Anatoly Frenkel

    There is a critical need for robust photosynthetic systems that can achieve efficient solar fuel production by CO2 reduction or water splitting. We combine highly efficient molecular catalysts with light-harvesting solid surfaces for use in solar CO2 reduction. In particular, coordination complexes of rhenium and cobalt have been coupled with mesoporous SiO2, TiO2, C3N4, and Si nanostructures. A variety of techniques, including infrared and X-ray absorption spectroscopies, were utilized to investigate CO2-reduction catalysis in these hybrid systems. Appropriate covalent linkages and catalyst/surface interactions were found to be important in promoting selective CO2 reduction.

  6. Chemistry Department Seminar

    ""Probing the Excited-State Reactivity of Transition-Metal Compounds Using Photophysics""

    Presented by Dr. Daniela M. Arias-Rotondo, Department of Chemistry

    Monday, September 23, 2019, 10 am
    Hamilton Seminar Room, Bldg. 555

    Hosted by: Matt Bird

    Transition metal compounds are ubiquitous throughout the chemical sciences, their presence broadly impacting fields such as organic synthesis and solar energy conversion. This talk illustrates how spectroscopic techniques can be used to understand the intricacies of reactions involving transition metal compounds towards two different applications. The first part of this presentation will focus on the conservation of spin in chemical reactions. Our group has previously shown that spin must be conserved for energy transfer to occur.1 To further our understanding of the effect of spin on other types of reactions, we have combined Ru(II) polypyridyls and Fe(III) oxo/hydroxo-bridged dimers to study how the spin state of the acceptor affects the rate of electron transfer. Through a combination of time-resolved spectroscopy and electrochemical techniques we have shown that excited spin states may be involved in electron transfer, as was predicted by Bominaar and coworkers in their studies involving metalloproteins.2 The second half of this seminar describes the use of energy transfer to activate traditional organometallic catalysts to unlock novel reactivity patterns. In particular, we studied the use of an Ir(III) photosensitizer in combination with a Ni(II) catalyst in the coupling of aryl halides and carboxylic acids.3 Mechanistic studies showed that energy transfer from the photocatalyst to the nickel species promotes the latter to an excited state that can promote a novel C-O bond formation.

  7. Chemistry Department Colloquium

    "Oxygen Catalysis for Large Scale Solar Energy Harvesting and Storage"

    Presented by Dunwei Wang, Boston College

    Thursday, September 12, 2019, 11 am
    Hamilton Seminar Room, Bldg. 555

    Hosted by: Anatoly Frenkel

    : As we enter Anthropocene, it has become clearer than ever that a sustainable future will be one built on renewable energy resources. A critical challenge in realizing such a goal is to harvest and store renewable energy efficiently and inexpensively on a terawatt scale. Of the options that have been examined, using the energy to directly synthesize fuels stands out. When the renewable energy source is solar, the process is often referred to as artificial photosynthesis, highlighting the similarities with natural photosynthesis. Within this context, we have focused on understanding the detailed processes that are important to artificial photosynthesis. More specifically, a main thrust of our research has been water oxidation by photochemical reactions on the surface of inorganic materials. We strived to understand the detailed physical and chemical processes at the solid/liquid interface, with the goal of enabling facile electron extraction from water for the eventual proton reduction for hydrogen generation or the carbon dioxide reduction for the production of complex organic compounds. It was discovered that the light harvesting and catalytic components in an integrated system exerts profound influences on each other in a complex fashion. Detailed studies generated new insights into the water oxidation reactions at the molecular level, some of which was readily transferred to other reactions such as methane transformation. These efforts also inspired us to study oxygen catalysis in aprotic systems for applications with more immediate implications, such as metal air batteries.

  8. Atmospheric Chemistry Colloquium for Emerging Senior Scientist

    "ACCESS XV"

    Saturday, July 27, 2019, 8 am
    Berkner Hall, Room B

    Hosted by: Ernie Lewis

  9. Atmospheric Chemistry Colloquium for Emerging Senior Scientist (ACCESS XV)

    "ACCESS XV"

    Friday, July 26, 2019, 8 am
    Berkner Hall, Room B

    Hosted by: Ernie Lewis

  10. Chemistry Department Seminar

    "Nanoparticle Beam Deposition: A Novel Route to the Solvent-Free"

    Presented by Richard E. Palmer, Nanomaterials Lab, Swansea University, UK, United Kingdom

    Tuesday, July 16, 2019, 11 am
    Room 300, 3rd Floor, Chemistry Building 555

    Hosted by: Michael White

    Size-selected nanoparticles (atomic clusters), deposited onto supports from the beam in the absence of solvents, represent a new class of model systems for catalysis research and possibly small-scale manufacturing of selective catalysts. To translate these novel and well-controlled systems into practical use, two major challenges have to be addressed. (1) Very rarely have the actual structures of clusters been obtained from direct experimental measurements, so the metrology of these new material systems have to improve. The availability of aberration-corrected HAADF STEM is transforming our approach to this structure challenge [1,2]. I will address the atomic structures of size-selected Au clusters, deposited onto standard carbon TEM supports from a mass-selected cluster beam source. Specific examples considered are the "magic number clusters" Au20, Au55, Au309, Au561, and Au923. The results expose, for example, the metastability of frequently observed structures, the nature of equilibrium amongst competing isomers, and the cluster surface and core melting points as a function of size. The cluster beam approach is applicable to more complex nanoparticles too, such as oxides and sulphides [3]. (2) A second major challenge is scale-up, needed to enable the beautiful physics and chemistry of clusters to be exploited in applications, notably catalysis [4]. Compared with the (powerful) colloidal route, the nanocluster beam approach [5] involves no solvents and no ligands, while particles can be size selected by a mass filter, and alloys with challenging combinations of metals can readily be produced. However, the cluster approach has been held back by extremely low rates of particle production, only 1 microgram per hour, sufficient for surface science studies but well below what is desirable even for research-level realistic reaction studies. In an effort to address this scale-up challenge, I will discuss the development of a new kind of nanop

  11. Nuclear Physics Seminar

    "Charm hadron collective flow and charm hadrochemistry in heavy-ion collisions"

    Presented by Xin Dong, Lawrence Berkeley National Laboratory

    Tuesday, July 2, 2019, 10 am
    Small Seminar Room, Bldg. 510

    Hosted by: Lijuan Ruan

    Heavy quark transport offers unique insight into the microscopic picture of the sQGP created in heavy-ion collisions. One central focus of heavy quark program is to determine the heavy quark spatial diffusion coefficient and its momentum and temperature dependence. This requires precise measurements of heavy flavor hadron production and their collective flow over a broad momentum region. In the meantime, heavy quark hadrochemistry, the abundance of various heavy flavor hadrons, provides special sensitivity to the QCD hadronization and also plays an important role for the interpretation of heavy flavor hadron data in order to constrain the heavy quark spatial diffusion coefficient of the sQGP. In this seminar, I will focus on the recent STAR results of charm hadron D0, D+/-, D*, Ds, Lambda_c production and D0 radial and elliptic flow in heavy-ion collisions utilizing the state-of-the-art silicon pixel detector, the Heavy Flavor Tracker. These data will be compared to measurements from other experiments at RHIC and the LHC as well as various model calculations. I will then discuss how these data will help us better understand the sQGP properties and its hadronization. Finally, I will present a personal view of future heavy quark measurements at RHIC.

  12. Chemistry Department Seminar

    "Chemical and Electrochemical Studies of Half-Sandwich Rhodium Complexes"

    Presented by James D. Blakemore, Dept. of Chemistry, University of Kansas

    Tuesday, July 2, 2019, 10 am
    Room 300, Chemistry Bldg. 555

    Hosted by: Etsuko Fujita

    Understanding the management of protons and electrons (reducing equivalents) by transition metal compounds is an active area of research, in part because of the role of reduced and/or protonated complexes in catalysis and energy conversion. We have been studying the chemistry of half-sandwich rhodium complexes in this regard, in order to reveal the influence of ligand structure on the outcomes of reduction and protonation reactions. Here, recent results on use of hybrid [P,N] and dipyridylmethane [N,N] chelate ligands will be discussed, including preparation and characterization of new compounds, chemical and electrochemical experiments aimed at elucidating new reactivity patterns, and studies of hydrogen evolution. Taken together, the results suggest that relatively underexplored ligands, as analogues of common diimine and diphosphine chelates, offer interesting new opportunities for influencing the properties and reactivity of metal complexes with protons and electrons.

  13. Chemistry Department Colloquium

    "Recent Advances in Soft X-ray Spectroscopy towards a Direct and Reliable Probe of Chemistry in Batteries"

    Presented by Wanli Yang, Lawrence Berkeley National Laboratory

    Thursday, June 27, 2019, 2 pm
    Hamilton Seminar Room, Bldg. 555

    Hosted by: Enyuan Hu

    The pressing demand of improved energy storage systems, especially for electric vehicles and green-grid, calls for speedy strategies for developing materials based on advanced analytic tools. Synchrotron based soft x-ray core-level spectroscopy is one of such incisive tools that probes the key electronic states pertaining to the performance of batteries. This colloquium starts with an in-depth introduction of conventional soft X-ray absorption spectroscopy (XAS) and X-ray emission spectroscopy (XES) with its applications in detecting the critical electron states in battery materials from binder to electrodes. The experimental results provide both general understandings and quantitative analysis of the transition-metal (TM) reactions at different electrochemical states, through direct probes of the K-edges (2p states) of low-Z elements such as C, O, N, and the L-edges (3d states) of 3d TMs. More importantly, however, we clarify that conventional spectroscopic experiments based on XAS do not really provide the claimed "elemental sensitivity" in either the O-K or the TM-L in the bulk-sensitive photon-in-photon-out mode, thus failing to detect the true signature of the bulk redox reactions of lower TMs, and especially, Oxygen [1]. This naturally requires advanced spectroscopic probes beyond conventional XAS for disentangle the mixed signals in oxides. We show that high-efficiency mapping of resonant inelastic X-ray scattering (mRIXS) beautifully solves the problems in both TM-L and O-K edge characterizations, providing clear experimental signatures of both the TM [2] and Oxygen [3] redox that cannot be distinguished in conventional XAS. This colloquium does not focus on technical discussions of a specific scientific study, instead, the focus will be on clarifying the principle and on how to correctly interpreting soft X-ray spectroscopic data instead of following popular misinterpretations. We finally note that recent advances in bo

  14. Chemistry Department Colloquium

    "Molecular catalysis of small molecules activation."

    Presented by Cyrille Costentin, Université Paris Diderot, France

    Monday, June 17, 2019, 11 am
    Hamilton Seminar Room, Bldg. 555

    Hosted by: Gerald Manbeck

    Solar-driven electrochemical splitting of water to molecular hydrogen and oxygen, along with the reduction of carbon dioxide are small molecule transformations that hold promise as routes of storing sunlight in energy-dense chemical bonds. Activation penalties require the help of catalysts, usually transition metal derivatives. We will provide the basic principles of molecular catalysis of electrochemical reactions based on the use of cyclic voltammetry as an analytical tool. Two examples will be discussed in details: (i) catalysis of the CO2-to-CO conversion with iron porphyrins to illustrate how mechanism analysis can lead to an intelligent design of a catalyst; new results on CO2 vs. acid reduction selectivity will be discussed; (ii) catalysis of the O2-to-H2O conversion with manganese porphyrins showing the crucial role of proton couple electron transfer (PCET) in the process.

  15. Chemistry Department Seminar

    "Designing Dopants to Shield Anion Electrostatics in Doped Conjugated Polymers to Obtain Highly Mobile and Delocalized Carriers"

    Presented by Taylor Aubry, UCLA

    Thursday, May 23, 2019, 11 am
    Room 300, 3rd Floor - Chemistry Bldg. 555

    Hosted by: Matthew Bird

    Doping conjugated polymers is an effective way to tune their electronic properties for thin-film electronics applications. Chemical doping of semiconducting polymers involves the introduction of a strong electron acceptor or donor molecule that can undergo charge transfer (CT) with the polymer. The CT reaction creates electrical carriers on the polymer chain (usually positive polarons a.k.a. holes) while the dopant molecules remain in the film as counterions. Undesirably, strong electrostatic attraction from the anions of most dopants will localize the polarons and reduce their mobility. We employ a new strategy utilizing substituted icosahedral dodecaborane (DDB) clusters as molecular dopants for conjugated polymers. DDBs provide a unique system in which the redox potential of the dopant can be rationally tuned via modification of the substituents without significant change to the size or shape of the dopant molecule. These clusters allow us to disentangle the effects of energetic offset on the production of free and trapped carriers in DDB-doped poly-3-hexylthiophene (P3HT) films. We find that by designing our cluster to have a high redox potential and steric protection of the core-localized electron density, highly delocalized polarons with mobilities equivalent to films doped with no anions present are obtained.1 P3HT films doped with these boron clusters have conductivities and polaron mobilities roughly an order of magnitude higher than films doped with conventional small-molecule dopants such as 2,3,5,6-tetrafluoro-7,7,8,8- tetracyanoquinodimethane (F4TCNQ). The spectral shape of the IR-region absorption for our DDB-doped polymer film closely matches the calculated theoretical spectrum for the anion at infinite distance from the polaron.2 We therefore conclude that these DDB clusters are able to effectively spatially separate the counterion. Moreover, nearly all DDB-produced carriers are free, while it has been shown that small m

  16. Chemistry Department Seminar

    "Atomic Quantum Clusters: Novel Materials at Sub-Nanometric Level"

    Presented by David Buceta, Nanomag Group, University of Santiago de Compostela, E-15782 Santiago de, Spain

    Wednesday, May 22, 2019, 11 am
    Room 300, Chemistry Bldg. 555 - 3rd floor

    Hosted by: Jose Rodriguez

    Atomic Quantum Clusters (AQCs) are formed by a small number of atoms (< ≈ 150) and represent a new family of compounds with novel and fascinating properties, which strongly differ from both, bulk and nanoparticles of the same material. For example, fluorescent, magnetic, catalytic, etc. properties have been found in AQCs1, which are not exhibited for the same material in larger sizes. In the last years soft chemical methods have been developed to synthesize AQCs without using protecting or capping ligands2, which may hinder their properties. This offers now the possibility to explore their properties in detail. In this talk it will be firstly summarized the state-of-the art of the kinetic-control synthesis methods, explaining in detail the mechanisms involved in such methods3. To show the precise control on the size of AQCs, which can be achieved with these methods, we will explain the synthesis of monodisperse samples of Cu5-AQCs and Ag3-AQCs. Secondly, we will focus on some important applications of clusters in catalysis, highlighting the particular consequences in biomedicine4.

  17. Chemistry Department Colloquium

    "Anineutrino Reactor Monitoring"

    Presented by Professor Patrick Huber, Virginia Tech

    Monday, March 4, 2019, 11 am
    Hamilton Seminar Room, Bldg. 555

    Hosted by: Minfang Yeh

    Nuclear reactors are the brightest man-made neutrino sources and have been the workhorse of neutrino physics since the discovery of the neutrino. In the 1970s Lev Mikaelyan realized that neutrinos also can be used to learn about the internal state of a nuclear reactor. The past decade has seen a significant increase in the interest in reactor neutrinos, thanks to the theta-13 experiments and the search for sterile neutrinos. In particular, I will discuss case studies we have performed for the historical case of the 1990s nuclear crisis in the Democratic People's Republic of Korea and for the IR-40 reactor in Iran. I will report on on-going efforts to develop suitable detectors for surface deployment close to a nuclear reactor and comment on the role coherent elastic neutrino nucleus scattering may play. With the most recent results from PROSPECT, CHANDLER and others, for the first time, a real world capability exists and I will present recent efforts by an international group of reactor neutrino experts with regards to North Korea, which were published in Science [Science, 362, (2018) 649-650)].

  18. Chemistry Department Colloquium

    "Atomic Simulation and Data Science Applied to Catalysis"

    Presented by Eric A. Walker, State University of NY at Buffalo

    Tuesday, February 19, 2019, 11 am
    Hamilton Seminar Room, Bldg. 555

    Hosted by: Ping Liu

    Atomic simulation is able to solve more chemical problems than ever before due to advances in high performance computing and data science tools. Two case studies are presented to illustrate this point. One case study is the water-gas shift reaction catalyzed by platinum clusters deposited on metal oxide (Pt/MO2). The water-gas shift reaction is the most widely applied reaction in industry for the production of hydrogen which is an environmentally-friendly fuel. Furthermore, water-gas shift may be conducted on domestically produced shale gas, alleviating foreign dependence on oil. Three hypotheses regarding the active site for the water–gas shift reaction are the interface edge of Pt/MO2 catalysts, the interface corner, and the platinum terrace (pure platinum). The hypotheses are tested against experimental kinetic data. Uncertainties associated with density functional theory (DFT) calculations and model errors of microkinetic models of the active sites are informed and verified using Bayesian inference and predictive validation on the experiments. Our results suggest the metal oxide support is essential for the activity of the catalyst for water-gas shift, which aids the rational design of catalysts for the water-gas shift reaction. In the second case study, large data sets of organic reactions are investigated using machine learning tools. Reactions which are not labeled with a solvent are automatically labeled, which impacts automated chemical process design and may be utilized as an every-day tool by chemists. The machine learning solvent selections are tested against an expert chemist. In a broad sense, the methods developed within this work improve the reliability of atomic simulations and the incorporation of machine learning to catalysis research.

  19. Chemistry Department Seminar

    "Theoretical and in situ studies for the reactivity of metal-ceria (111) surfac-es: Importance of strong metal-support interactions"

    Presented by M. Verónica Ganduglia-Pirovano, Instituto de Catálisis y Petroleoquímica Consejo Superior de Investigaciones Científicas,, Spain

    Friday, February 15, 2019, 11 am
    Room 300, 3rd floor, Chemistry Bldg. 555

    Hosted by: Sanjaya Senanayake

    Metal-ceria catalysts are promising systems for industrially important reactions such as the water-gas shift reaction for hydrogen production, methane dry reforming (DRM: CH4+CO2 ? 2H2+2CO), and the direct conversion of methane to methanol (DMTM: CH4+ ½ O2 ? CH3OH). However, the complexity of real (powder) catalysts hinders the fundamental understanding of how they work, which is essential for their rational design. Specifically, the role of ceria in the catalytic activity of ceria-based systems is still not fully understood. To unravel it, well-defined ceria-based model cata-lysts consisting of metal nanoparticles deposited on a ceria surface are prepared experimentally or created theoretically and investigated. In this talk, recent results on ceria-supported Ni, Co and Cu model catalysts will be discussed, as examples of catalysts for DRM.1-3 The emphasis is here put on theoretical studies in combination with experiments using ambient pressure X-ray photoelectron spectroscopy, and special attention is given to the effects of ceria as catalyst support. The ability of ceria to stabilize oxidized species (MOx: Co2+ and Ni2+) on the CeO2 surface, by relocalizing electrons on localized f-states, and metal-lic ones (Co0, Ni0) on the reduced CeO2-x support, is essential for CH4 activation ?that occur at tem-peratures as low as 300 K? and its reforming at relatively low temperatures (~700 K). Also, the Ni/ceria system is considered for H2O activation and methanol synthesis from methane and wa-ter.4,5

  20. Condensed-Matter Physics & Materials Science Seminar

    "Novel Electrochemistry for Fuel Cell Reactions: Efficient Synthesis and New Characterization Methods"

    Presented by Zhixiu Liang

    Wednesday, February 6, 2019, 4:30 pm
    Bldg. 480 Conference Room

    Hosted by: Jing Tao

    The ever increasing consumption of fossil fuels for transportation causes climate change causing a growing concern about their future availability and further adverse environmental effects. To address this issue, the concept of CO2 neutral fuels-based energy cycle was brought out. The key reactions in that concept are electrochemical methanol oxidation (MOR), ethanol oxidation reaction (EOR), and CO2 reduction reaction (CO2RR). These all are elctrocatalysis research challenges being slow even at the best catalyst that hamper application of fuel cells, and bring environmental benefits. My research made these improvements of catalysts for the key reactions. In-situ electrochemical infrared reflective absorbance spectrum (EC-IRRAS) reveals that at lower temperature, such reaction is not complete and generates more formate; at elevated temperature, such reaction is complete to carbonate. Ethanol is one of the ideal fuels for fuel cells, but requires highly improved catalysts. Au@PtIr/C catalyst was synthesized with a surfactant-free wet-chemistry approach. Transmission electron microscope (TEM) characterization confirms the monolayer/sub-monolayer Pt-Ir shell, gold core structure. The catalyst has a very high mass activity of 58 A/mg at peak current. In situ EC-IRRAS reveals that C-C bond is cleaved upon contact with the catalyst surface leading to ethanol complete oxidation to CO2. Related researches on methodologies, included in situ TEM to help obtaining catalysts improvements, give morphologic, structural and spectroscopic information at wide range from hundreds of microns to sub-nanometer coupled with various detectors. Microelectromechanical System (MEMS) based chips technology enables TEM observation in operando, with liquid-flow-cell chips and electrochemistry chips designed and fabricated. Ag@Au hollow cubes synthesis via galvanic replacement of Au on Ag cubes was investigated with in situ TEM. The results demonstrate abnormal react

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