In preparation for the Gold 2022 conference, a series of webinars on each one of the main scientific topics will be organized by the conference chairs and the local committee. Each webinar will be held on fixed dates. It will be chaired by an expert in the field, appointed by the organization committee. Each webinar will include talks from two (2) invited experts in the field: one (1) international expert whose research was highlighted by several papers published in high-impact factor journals in the last 3 years (since Gold 2018), and one (1) international expert based in Canada, who will also project the recent research advances in the field in the Country. We believe that this approach will lead to high-quality scientific discussions while arousing the interest of the scientific community for research taking place both internationally as well as in the host country. It will also help the international scientific community to connect with local experts during Gold 2022.
The total duration of each webinar will be 90 minutes.
Wednesday, June 23, 2021, 11h00 - 12h30 Eastern Daylight Time
Chair: Faïçal Larachi, Université Laval, CanadaPresentations:
Environmental Effects of Gold Mining in Canada: Past, Present and FutureThe mining and milling of gold can result in significant risks to the environment and human health without appropriate mine planning, environmental management, and monitoring programs. Mining has been an important part of the Canadian economy for at least the last 150 years and many early mines were operated before the enactment of modern environmental regulations. The environmental legacy of these historical mining practices has led to more stringent regulations and new technologies to improve environmental stewardship within the mining sector. However, there remain significant gaps in our understanding of baseline conditions in mining areas, the long-term behaviour of mine wastes, and uncertainty regarding the most appropriate strategies to monitor the success of remediation efforts. This webinar will provide a brief overview of the main types of gold deposits in Canada and some of the key environmental concerns at both historical and modern gold mines across the country. I will summarize results from recent studies in Nova Scotia on the environmental effects of past gold mining and how this knowledge is now being used to clean-up abandoned mines and guide environmental management for new gold mine sites.Michael B. Parsons, Ph.DResearch Scientist, Environmental Geochemistry
Natural Resources Canada, Geological Survey of Canada (Atlantic)Canada
Dr. Michael Parsons is a Research Scientist with the Geological Survey of Canada – Atlantic in Halifax, Nova Scotia. He received a Combined Honours B.Sc. in Earth Sciences and Chemistry from Dalhousie University in 1994, and a Ph.D. in Geological and Environmental Sciences from Stanford University in 2001. His research focuses on the sources, cycling, and fate of metals in the environment. He is particularly interested in the environmental impacts of mining operations, and has led multidisciplinary projects at active and abandoned metal mines across Canada. His current research projects focus on the geoenvironmental characteristics of critical metal deposits, optimizing remediation methods for mine wastes, and characterizing the effects of climate change on metal mines in northern Canada. Dr. Parsons holds Adjunct Professorships at Dalhousie and Queen’s universities and regularly co-supervises students who are involved in his research activities. Results of his research provide a better understanding of the ecosystem and human health risks associated with metals and have been used to develop improved environmental guidelines and to help manage contaminated sites.
Wednesday, May 26, 2021, 10h00 - 11h30 Eastern Daylight Time
Chair: Dr Denis Boudreau, Centre d'optique, photonique et laser - Université Laval, CanadaPresentations:
Frontiers in Nanophotonics: Enabling Technology for Next-Generation BiosensorsEmerging healthcare needs and initiatives, including global health crisis, personalized medicine, point-of-care applications are demanding breakthrough advancements in bioanalytical and diagnostics tools. Biosensors play an essential role in disease diagnostics, but current devices are lacking precision, affordability, and portability. Furthermore, they require long detection times, sophisticated infrastructure, and trained personnel, which limit their broader applicability. In our laboratory, we address these challenges by developing next-generation nanophotonic biosensors, bioimaging, and spectroscopy technologies. The expertise of our lab covers a variety of techniques, including nanophotonics, nanofabrication, microfluidics, surface chemistry, and data science. In particular, we exploit nanoplasmonics and metasurfaces, which can confine light below the fundamental diffraction limit and generate strong electromagnetic fields at nanometric volumes for achieving high device performance. We develop new nanofabrication methods for high-throughput and low-cost manufacturing of nanophotonic biochips. We integrate our sensors with micro/nanofluidic systems for efficient analyte trapping, sample manipulation, and automation. We also use smart data science tools with hyperspectral and bioimaging for aided signal processing. In this talk, I will present some of our recent effort in these directions using gold as the main nanoplasmonic material [1-8]. For example, I will introduce ultra-sensitive Mid-IR biosensors based on surface-enhanced infrared spectroscopy for chemical-specific detection of molecules, large-area chemical imaging, and real-time monitoring of protein conformations in aqueous environment. I will describe our effort to develop ultra-compact, portable, rapid, and low-cost microarrays and their use for early disease diagnostics in real-world settings. I will also highlight our label-free optofluidic biosensors that can perform one-of-a-kind measurements on live cells down to the single-cell level, and provide their overall prospects in biomedical and clinical applications..
Dr Hatice Altug
École Polytechnique Fédérale de Lausanne (EPFL)
Institute of Bioengineering
Hatice Altug is full professor in the Institute of Bioengineering at Ecole Polytechnique Federale de Lausanne (EPFL), Switzerland. She is also the director of EPFL Doctoral School in Photonics. Between 2007 and 2013, she was professor in the Electrical and Computer Engineering Department at Boston University, U.S. She received her Ph.D. in Applied Physics from Stanford University (U.S.) in 2007 and her B.S in Physics from Bilkent University (Turkey) in 2000.
Prof. Altug is the recipient of the U.S. Presidential Early Career Award for Scientists and Engineers in 2011, which is the highest honor bestowed by the United States government on outstanding scientists and engineers in their early career and Optical Society of America Adolph Lomb Medal in 2012, which is presented to a person who has made a noteworthy contribution to optics at an early career stage. In 2020, she received the European Physical Society Emmy Noether Distinction for Women in Physics her seminal contributions to light-matter interaction at the nanoscale, manipulation of light on-chip and application of nanophotonics in biology, and her inspiring role for the next generation of researchers and women. She is an elected fellow of the Optical Society of America. She received prestigious grant awards in Europe and USA including the European Research Council (ERC) Consolidator Grant, ERC Proof of Concept Grant, U.S. Office of Naval Research Young Investigator Award, U.S. National Science Foundation CAREER Award, Massachusetts Life Science Center New Investigator Award, IEEE Photonics Society Young Investigator Award. She won Inventors’ Challenge competition of Silicon Valley in 2005. She has been named to Popular Science Magazine’s "Brilliant 10" list in 2011.
Prof. Altug’s research pioneers in the fields of nanophotonics and its application to biosensing, spectroscopy and bioimaging. Her laboratory’s expertise cover optics, microfluidics, micro/nanofabrication, biochemistry to data science. They introduce next-generation bianalytical technologies for label-free, real-time, and high-throughput analysis on biomolecules, pathogens and living systems for basic research in life sciences, disease diagnostics and point-of-care testing.
SERS optophysiology of metabolites near or inside cellsSurface enhanced Raman scattering (SERS) optophysiology is a Raman method using nanofibers decorated with a dense and well dispersed array of Au NP for the measurement of neurotransmitters and other metabolites in proximity of cells. Using a pulled nanofiber (tip diameter below 1 um) and polymer assembly of Au NPs on the tip creates a highly sensitive SERS sensor that can be accurately positioned in space with a micromanipulator. The nanosensors are thus highly compatible with current physiology experiments also relying on similar nanosensors based on electrochemistry and electrophysiology. The SERS spectra are associated to single molecule measurements and were identified with a barcoding data processing method, processed with TensorFlow. This machine-learning driven data processing significantly improved the positive assignment rates for a series of neurotransmitters and metabolites, allowing for complex measurements of the brain’s neurochemistry or associating differences in cellular metabolism of healthy and cancer cells. Specifically, this presentation will show our efforts in the development and the optical properties of SERS nanofibers, the construction of a SERS optophysiology microscope and the applications of the technique in cultured brain neurons and a series of healthy vs. cancer cell experiments. Of particular interest, the measurement of complex molecular gradients will be demonstrated close to cells.
Dr Jean-François Masson
Université de Montréal
Jean-François Masson is full professor of Chemistry at the Université de Montréal. He studied chemistry at the Université de Sherbrooke (BSc), Arizona State University (PhD) and Georgia Tech (postdoc). His laboratory develops new plasmonic materials, instruments, and surface chemistry for the detection of broad range of molecules directly in crude samples, which are then translated to functional sensors for a series of biological, environmental and industrial applications. He has published more than 125 research articles and his research has led to filing more than 10 patents on various instrumental, materials or surface chemistry innovations for biosensing. He is an Associate Editor for ACS Sensors. In 2015, he co-founded Affinité Instruments, a Canadian start-up company commercializing surface plasmon resonance (SPR) instrumentation. Jean-Francois received several awards including the Tomas Hirschfeld award (2005), a NSERC discovery accelerator (2011), the Fred Beamish award (2013) and the McBryde Medal (2019) of the Canadian Society for Chemistry, and an Alexander von Humboldt fellowship, Germany (2013-2014) for research at the Max-Planck Institute. In 2017, he was named Fellow of the Royal Society of Chemistry – UK and more recently, he was named in the 2018 power list of the top 40 under 40 analytical scientists and the 2019 power list of the top 100 most influential analytical scientists from The Analytical Scientist - UK.
Wednesday, March 24, 2021, 11h00 - 12h30 Eastern Daylight Time
Chair: Dr Marc-André Fortin, CR-CHU de Québec- Université Laval, CanadaPresentations:
Nanophotonic Approaches for Chirality SensingChiral nanophotonic materials are promising candidates for biosensing applications because they focus light into nanometer dimensions, increasing their sensitivity to the molecular signatures of their surroundings. Recent advances in nanomaterial-enhanced chirality sensing provide detection limits as low as attomolar concentrations (10-18 M) for biomolecules and are relevant to the pharmaceutical industry, forensic drug testing, and medical applications that require high sensitivity. Chiral nanomaterials have potential applications in detecting biomolecules, supramolecular structures, and other environmental stimuli. I will discuss the plasmon-coupled circular dichroism mechanism observed in plasmonic nanoparticles and discuss how hotspot-enhanced plasmon-coupled circular dichroism applies to biosensing. I then will discuss single-particle spectroscopic methods for achieving the ultimate goal of single-molecule chirality sensing. Finally, I will propose future directions for nanophotonic chiral systems.
Dr Christy F. Landes
Department of Chemistry
Christy F. Landes is a professor in the Department of Chemistry at Rice University in Houston, TX, with appointments in the Departments of Electrical and Computer Engineering, and Chemical and Biomolecular Engineering. After graduating with a BS from George Mason University in 1998, she completed a Ph.D. in Physical Chemistry at the Georgia Institute of Technology in 2003 under the direction of Prof. Mostafa El-Sayed. She was a postdoctoral researcher at the University of Oregon and an NIH postdoctoral fellow at the University of Texas at Austin, under the direction of Prof. Geraldine Richmond and Prof. Paul Barbara, respectively, before joining the University of Houston as an assistant professor in 2006. She moved to her current position at Rice in 2009.
Christy is an active member of the American Chemical Society and the Physical Chemistry Division, and will serve as Vice-Chair Elect, Vice-Chair, Chair-Elect and Chair of the Division from 2020-2023. One of her interests is in bringing scientists together to form communities that span different areas of expertise. She has organized national, regional, and local symposia. She serves as a senior editor of the Journal of Physical Chemistry Letters, on the Editorial Committee of the Annual Review of Physical Chemistry on the Editorial Advisory Board of ACS Nano. Christy is a member of the American Association for the Advancement of Science, the American Physical Society, and the Institute of Electrical and Electronics Engineers. She also served on the Defense Science Study Group from 2016-2018, and this experience was life changing.
The Landes Group is comprised of chemists, applied physicists, and engineers who develop next-generation tools to image dynamics at soft interfaces at the limit of a single event. Her group devises new methods and models for controlling macroscale processes such as protein separations and photocatalysis using this super-resolved chemical knowledge. The group also uses advanced signal and image processing methods to improve accuracy and precision in low-signal measurements. Christy’s outreach activities emphasize the importance of mathematics and computer programming in our increasingly data-driven world. Her goal for the community goal is to underscore our common values despite the expanding need to broaden and redefine our respective specializations.
Christy earned an NSF CAREER award for her tenure-track work in 2011 and the ACS Early Career Award in Experimental Physical Chemistry in 2016. In 2019, she was selected as a Kavli Frontiers of Science Fellow.
Dr Stephan Link
Department of Chemistry
Stephan Link is Professor of Chemistry and of Electrical and Computer Engineering at Rice University in Houston. He received his Ph.D. in chemistry in 2000 from the Georgia Institute of Technology where he worked for Professor Mostafa A. El-Sayed. In 2006, he joined the Rice Chemistry Department after postdoctoral positions at Georgia Tech and the University of Texas at Austin, where he worked for Professor Paul F. Barbara. His main research interests include the optical properties of single and assembled metallic nanoparticles. He has published over 150 articles in the field of plasmonic nanostructures and is currently a Senior Editor for The Journal of Physical Chemistry.
Molecular-Scale Ligand Effects in Small Gold-Thiolate NanoclustersBecause of the small size and large surface area of thiolate-protected Au nanoclusters (NCs), the protecting ligands are expected to play a substantial role in modulating the structure and properties. However, little is known on how thiolate ligands explicitly modulate the structural properties of the NCs at atomic level, even though this information is critical for predicting the performance of Au NCs in application settings (e.g., catalyst interacting with small molecules, sensor interacting with biomolecular systems). This talk will review a recent combined experimental and theoretical study – using synchrotron X-ray spectroscopy and quantum mechanics/molecular mechanics simulations – that investigates how the protecting ligands impact the structure and properties of small Au18(SR)14 NCs (SR - thiolate ligand). Two representative ligand types – smaller aliphatic cyclohexanethiolate and larger hydrophilic glutathione – are selected and their structures are followed experimentally in both solid and solution phases. It was found that cyclohexanethiolate ligands are significantly perturbed by toluene solvent molecules, resulting in structural changes that cause disorder on the surface of Au18(SR)14 NCs. In particular, large surface cavities in the ligand shell are created by interactions between toluene and cyclohexanethiolate. In contrast, glutathione ligands encapsulate the Au NC core via intermolecular interactions, minimizing structural changes caused by interactions with water molecules. The protection from glutathione ligands imparts a rigidified surface and ligand structure, making the NCs desirable for biomedical applications due to the high stability and offering a structural-based explanation for the enhanced photoluminescence often reported for glutathione-protected Au NCs.
Dr Daniel Chevrier
Bioscience and Biotechnology Institute of Aix-Marseille
CEA Cadarache, France
Dr. Daniel Chevrier completed his PhD in chemistry at Dalhousie University (Halifax, Nova Scotia, Canada) in 2017 under the supervision of Dr. Peng Zhang. Dr. Chevrier’s research involved the study of noble metal nanocluster structure and properties through use of X-ray spectroscopy with a focus on luminescent thiolate-gold nanoclusters. He then pursued postdoctoral research on magnetite biomineralization at the Max Planck Institute for Colloids and Interfaces (Golm, Germany) and the Biosciences and Biotechnologies Institute of Aix-Marseille (BIAM) (Cadarache, France) as a Marie Curie postdoctoral fellow (MSCA-IF). Dr. Chevrier is now a CNRS researcher at BIAM and is specializing in the use of X-ray spectromicroscopy techniques to investigate microorganism-based biomineralization processes.
Wednesday, February 17, 2021, 11h00 - 12h30 Eastern Time
Chair: Dr Olivier Pluchery, Université de la Sorbonne, FrancePresentations:
Thermoplasmonics: Let’s do something useful with metal lossesRecent years have witnessed a growing interest in controlling temperature on the nanoscale motivated by applications to different fields, including information technology, chemistry and medicine. Under illumination at its plasmon resonance, a gold nanoparticle features enhanced light absorption, turning it into an efficient nano-source of heat, remotely controllable by light. By combining efficient light-to-heat conversion, strong temperature gradients and fast time dynamics, plasmon-enabled heating (also known as Thermoplasmonics) opens a wide range of new opportunities over standard heating schemes. In this talk, following a general introduction about the main assets of Thermoplasmonics, we will present some of our recent research on several novel applications, from on-a-chip biosensing and additive manufacturing to implant disinfection and fibrosis treatment.
Dr Romain Quidant
Nanophotonic Systems Laboratory
Department of Mechanical and Process Engineering
I received a PhD in Physics (2002) from the University of Dijon, in France. Right after defending my thesis, I joined ICFO as a postdoctoral researcher. This was the year of its creation and I was lucky enough to get actively involved into the early developments of the Institute. In 2006, I was appointed junior Professor (tenure-track) and group leader of the Plasmon NanoOptics group at ICFO. In 2009, I became tenure Professor both at ICFO and ICREA (Catalan Institution for Research). After nearly 18 years at ICFO, in June 2020, I joined the Mechanical and Process Engineering department (D-MAVT) at ETH Zurich. I am recipient of 5 ERC grants (StG2010, PoC2011, PoC2015, CoG2015 and SyG2020) and several international and national prizes (Fresnel2009, City of Barcelona 2010, International Commission for Optics 2012, National research Prize 2014, Banc Sabadell 2017). I serve as the executive editor of ACSPhotonics (American Chemical Society).
Our research focuses on nano-optics, at the interface between Photonics (the science of light) and Nanotechnology. We use the unique optical properties of nanostructures as an enabling toolbox to design solutions to scientific and technological challenges, in a wide set of disciplines, from fundamental physics to biotechnology and medicine. This makes our group highly interdisciplinary and involved in both basic and applied research. The most fundamental part of our work is mainly directed towards enhanced light/matter interaction and optomechanics. From a more applied viewpoint, our team investigates news strategies to control light and heat at the nanometer scale for biomedical applications, including lab-on-a-chip technology and targeted hyperthermia and for reconfigurable planar optics.
Plasmonics nanoparticles for use in theranosticsPlasmonic nanoparticles such as gold, silver or their alloys are interesting nanomaterials for their applications in therapeutics and diagnostics in nanomedicine. In this presentation, I will present recent developments performed in this field at Polytechnique. A new method for delivering exogenous biomolecules into targeted cells using an ultrafast laser and plasmonic nanoparticles will be presented. The technique of plasmon-mediated laser nanosurgery has been used to effectively perform gene transfection in various living cells and delivery of biomolecules in vivo in animal model for ophthalmic applications. This technology has been also used for locally stimulating neurons to control neuronal activity and cell signaling. Moreover, alloy nanoparticles have been synthesized using an improved seeded-growth approach. These spectrally distinctive plasmonic nanoparticles are used as biomarkers to perform quantitative multiplexed 3D imaging of cells and tissues. Our techniques show promises of innovative tools for basic research in biology and medicine as well as effective alternative technologies that could be adapted to the therapeutic, diagnostic, theranostics tools of the clinic.
Dr Michel Meunier
Engineering Physics Department
Michel Meunier obtained a PhD from MIT in 1984. In 1985, he began his career at Polytechnique Montreal and he was promoted to full professor in 1993. Holder of a Canada Research Chair Tier 1 and co-founder of LTRIM Technologies, Michel Meunier is also a laureate, in 2006, of a Synergy Award for Innovation. He is a Fellow of the Canadian Academy of Engineering, as well as OSA and SPIE. In 2016, he won the Guy Rocher Award for his excellence in teaching at the university level. His intense research activities focus on the development of new optical nanomaterials, nano-optical devices and laser technology for nanomedicine applications. He has published more than 380 articles and supervised more than 120 graduate students and postdoctoral fellows. Since June 1st 2019, he is the Head of the Engineering Physics department.
Wednesday, January 20, 2021, 19h00 - 20h30 Eastern Time
Chair: Dr Daniel B. Leznoff, Simon Fraser University, CanadaPresentations:
Recent Advances in Luminescent Gold-Containing Molecular Functional MaterialsIn this webinar, recent advances in the design and synthesis of novel classes of luminescent gold complexes with functional properties will be described. The chromophoric and luminescence properties have been studied and their spectroscopic origins elucidated. Correlations of the chromophoric and luminescence behavior with the electronic and structural properties of the gold complexes have been made. The characteristics of these complexes can be tailored for specific applications including as molecular materials for optoelectronics, electronics and stimuli-responsive functions.
Dr Vivian Wing-Wah Yam
Institute of Molecular Functional Materials and Department of Chemistry
The University of Hong Kong
P. R. China
Vivian W.-W. Yam obtained both her BSc (Hons) and PhD from The University of Hong Kong, and is currently the Philip Wong Wilson Wong Professor in Chemistry and Energy and Chair Professor of Chemistry at The University of Hong Kong. She was elected to Member of Chinese Academy of Sciences, International Member (Foreign Associate) of US National Academy of Sciences, Foreign Member of Academia Europaea, Fellow of TWAS and Founding Member of Hong Kong Academy of Sciences. She was Laureate of the 2011 L'Oréal-UNESCO For Women in Science Award. Her research interests include inorganic/organometallic chemistry, supramolecular chemistry, photophysics and photochemistry, and metal-based molecular functional materials for sensing, organic optoelectronics and energy research.
Coordination and Metallic Clusters of Gold with New Ligand TypesThe chemistry of atomically precise gold clusters continues to develop at a rapid pace. In the first part of this seminar, how N-heterocyclic carbene (NHC) ligands play an emerging role in gold-chalcogenide cluster science will be highlighted. NHCs can be used to effectively stabilize polymetallic assemblies of Au(I) and, when merged with the rich luminescence features of heterometallic group 11-chalcogenide clusters, they offer an ability to probe composition/structure/property relationships systematically. This has enabled a series of isostructural coordination clusters [(NHC)4Au4M4(μ3-E)4] (M = Ag, Au; E = S, Se, Te) to be prepared where systematic replacement of the central metals and/or chalcogen is possible. Phosphorescence is observed from all clusters and emission energies can be varied based on the choice of metal and chalcogen within structurally identical cluster cores. Higher nuclearity cluster frameworks are also accessible using this approach. In the second part of this seminar, the tailoring of Au nanoclusters via interfacial surface chemistry will be described. In a collaborative work, the thiolate surfaces of monodisperse [Au25(SCH2CH2-C6H4-N3)18]- platforms that contain azide moieties as part of the ligands are being developed, the make-up of the surfaces confirmed by single crystal X-ray analysis and spectroscopic techniques. The -N3 moieties can undergo strain-promoted alkyne-azide cycloaddition reactions on the cluster surfaces, enabling selective incorporation of functionality with retention of the Au25 frameworks.
 J. Am. Chem. Soc., 2017, 139, 14045-14048.
 Dalton Trans., 2020, 49, 593-597.
 J. Am. Chem. Soc., 2019, 141, 11781-11785.
Department of Chemistry
John F. Corrigan is a Professor in the Department of Chemistry at Western University London, Ontario, Canada. He obtained his B.Sc. (Chemistry Specialist) from the University of Toronto and his Ph.D. from the University of Waterloo. His research interests are located on the frontiers between coordination chemistry, materials chemistry and nanosciences: his team targets molecular clusters and functional nanomaterials with the design of molecules that are incorporated into more complex architectures (“molecular precursor approach”).
Wednesday, December 16, 2020, 11h00 - 12h30 Eastern Time
Chair: Dr Alexandre Brolo, University of Victoria, CanadaPresentations:
Fundamentals and Applications of Electrodeposited Au from Pyridine-Derivative Containing SolutionsTetrachloroaurate is, by far, the most popular precursor used in the formation of gold nanoparticles. However, AuI species have been championed as potentially better precursors because of the lower energy associated with one versus three electron transfer, the larger thermodynamic driving force for the reduction of AuI compared to AuIII, and the use of AuI-complex ligands as in situ capping agents and growth directing mediators. Empirically, we have observed evidence of the spontaneous formation of a AuI species upon the addition of 4-methoxypyridine (Py/) to aqueous tetrachloroaurate (AuCl4-) solutions. In this seminar, fundamental studies of the (electro)chemistry of the tetrachloroaurate- Py/ system are described that reveal the co-existence of both AuIII and AuI species. The observation of a slow, but spontaneous, conversion of AuIII species to AuI species is explained by demonstrating that the oxidation of the pyridine derivative drives a galvanic reaction involving a AuIII/AuI redox couple. Electrodeposition of metallic gold onto ITO electrodes from these solutions leads to the formation of highly anisotropic nanoparticles and can be (at least partially) attributed to the disproportionation of AuI and the preferential adsorption of Py/ on certain crystallographic facets of growing electrodeposits. The resulting gold modified substrates have excellent applications as bimodal platforms for surface enhanced vibrational spectroscopies. Dagger shaped gold particles have been electrodeposited on surfaces of conductive indium tin oxide (ITO) films. The optical extinction of these AuND@ITO substrates extends from the near-IR to long wavelength mid-infrared frequencies. AuND@ITO substrates are assessed as potential enhancing interfaces for dual modality, spectroelectrochemical, surface sensitive vibrational spectroscopy; specifically surface enhanced Raman spectroscopy (SERS) using 1064 nm excitation and attenuated total reflectance surface enhanced infrared absorption spectroscopy (ATR-SEIRAS) using a broadband emission source.
Dr Ian Burgess
Department of Chemistry
University of Saskatchewan,
Dr. Ian Burgess is a Professor in the Department of Chemistry, at the University of Saskatchewan in Saskatoon, Canada. His expertise is in the adsorption of metal-nanoparticle stabilizing molecules, infrared spectroelectrochemistry and infrared imaging. He is the beamteam leader of the mid infrared beamline at the Canadian Light Source (CLS)- Canada's synchrotron facility. He has developed advanced FTIR investigations of gold electrode surfaces using SEIRAS (surface enhanced infrared absorption spectroscopy) and has developed microfluidic imaging capabilities at the midIR beamline at the CLS.. He has published over 90 papers and three book chapters. He is a co-founder of Jackfish SEC, a spinoff company based in Saskatoon that makes specialty equipment for infrared spectroelectrochemistry.
Wednesday, November 25, 2020, 11h00 - 12h30 Eastern Time
Chair: Dr Graham Hutchings,Cardiff University, United KingdomPresentations:
Harvesting the free energy of light using goldIn my talk, I will show that the photoexcitation of plasmon resonances in gold nanoparticles induces new catalytic behavior in gold enabling redox transformations that are otherwise not possible. For instance, we have found that under visible light excitation, gold nanoparticles catalyze the kinetically challenging, multi-electron, multi-proton reduction of CO2 to hydrocarbons. The redox conversion is triggered by energetic electron–hole pairs generated in the gold nanoparticles by interband damping of the plasmon resonance. C–C coupling to form longer hydrocarbons is observed in this light-driven process, which suggests that photoexcitation induces a reaction pathway distinct from that in a thermocatalytic process. The product selectivity is tuned by light intensity and photon energy. Finally, I will show that this scheme goes well beyond photocatalysis: free energy can be harvested from plasmonic excitations of Au nanoparticles and stored in the form of energetic chemical bonds.
Dr Prashant K. Jain, PhDPrashant K. Jain grew up in Bombay, where he completed his undergraduate education. He obtained his PhD working with M. A. El-Sayed at Georgia Tech, following which he was a postdoctoral fellow at Harvard. After a Miller Fellowship at UC Berkeley, he joined the faculty of the University of Illinois at Urbana-Champaign, where he is an Alumni Scholar and Professor in the Department of Chemistry, Materials Research Lab, and the Beckman Institute. He is also a Richard and Margaret Romano Professorial Scholar and an Affiliate Faculty Member in Physics. His research webpage can be found at https://nanogold.org. Prashant’s lab studies light–matter interactions on the nanoscale. His lab is best known for using nanoscale-confined light for artificial photosynthesis and for probing the workings of complex materials and catalysts. His lab has also expanded the phenomenon of plasmon resonances beyond metal nanostructures to semiconductor nanocrystals. His collective work has been cited over 23,700 times. He has been listed among Highly Cited Researchers by Clarivate Analytics and Elsevier Scopus. Prashant is a Fellow of the Royal Society of Chemistry, a TR35 inventor, a Sloan Fellow, and a recipient of the Presidential Early Career Award in Science and Engineering. He serves on the Editorial Advisory Board of the Journal of Physical Chemistry and is the lead developer of nanoDDSCAT, an open-source computational toolkit for nano-optics and photonics.
Department of Chemistry
University of Illinois Urbana-Champaign,
The Tale of the two Golds: Gold on Chitosan Nanocrystals as a versatile Platform in Catalysis and Mechanochemistry as a novel Method to access Gold NanoparticlesWe explored the use of carboxylated chitin nanocrystals (ChNCs) and their deacetylated versions chitosan nanocrystals (ChsNCs) as support material for gold-based catalysts. ChNCs were initially prepared through the treatment of chitin by ammonium persulfate. ChsNCs were subsequently prepared using an alkaline deacetylation procedure in the presence of NaBH4 to preserve the nanorod structure of the biomaterial. Subsequently, we tested the ability of the as-made ChNCs and ChsNCs as support for Au species. In a reductive environment, these acted as highly active catalysts for the 4-nitrophenol reduction, while the aldehyde–amine–alkyne (A3) coupling reactions functioned very well with these systems, demonstrating the ability to stabilize a Au(I) form. Spectroscopic and imaging techniques confirmed the importance of precisely controlling the redox state of Au as it is being deposited to afford a highly disperse active site on the bionano-support. In another example, we developed a novel synthetic method for the scalable production of gold nanoparticles (NPs) under solvent-free, mechanochemical conditions. The synthesis of Au NPs provided access to monodisperse and ultra-small NPs in the size range of 1–4 nm, without external reducing agents or bulk solvents. Using lignin as a biomass-based reducer, we could access embedded Au NPs of Au in on pot.
Sources: Biomacromoleculese 2020, 21, 6, 2236–2245 and Green Chem., 2014, 16 (1), 86-89
Audrey Moores, PhDAudrey Moores is an Associate Professor of Chemistry and Tier II Canada Research Chair in Green Chemistry (2007-17) at McGill University, where she started her independent career in 2007. She completed her PhD from the Ecole Polytechnique, France in 2005, under the supervision of Prof. Pascal Le Floch and received the Best Thesis award of the Ecole Polytechnique that year. She was a post-doctoral fellow at Yale University in 2006 under the guidance of Prof. Robert H. Crabtree, funded by a Lavoisier fellowship from the European Union. She is a leading expert in the field of catalysis using metal, metal oxide and biomass-based nanomaterials, with a special emphasis on sustainable processes and use of earth abundant starting materials. Specifically, she has made important discovery towards the use of iron for the important hydrogenation and oxidation catalytic reactions and replace noble metals as catalysts. She is also developing entirely novel methods towards the synthesis of size controlled nanomaterials under solvent-free conditions. She is also studying novel photo catalysts based on plasmonic materials. Her scientific work has been published in 80 high profile, peer reviewed publications, such as J. Am. Chem. Soc., Green Chem., Chem. Comm., or ACS Sustainable Chem. Eng. She also authored 7 book chapters, 1 book and 3 patents (>4700 citations & h-index 35 from Google Scholar). She was elected in 2020 as a Member of the College of the New Scholars, Artists and Scientists of the Royal Society of Canada.
Center for Green Chemistry and Catalysis
Department of Chemistry
Webinar's Topics to come:
- Synthesis of nanoparticles and nanostructures
- Gold-containing molecular and supramolecular complexes
- High-purity gold synthesis and recycling
- Plasmonics (fundamentals, engineering and systems)
- Electronics, optics and photonics
- Biomedical applications of gold: in vivo applications and technologies, injectable nanoparticles and pharmacology
- Biomedical applications of gold: sensors and devices
- Computational approaches, machine learning and artificial intelligence (AI)