Mark Workentin, Western University
Department of Chemistry
Professor
London, Ontario
mworkent@uwo.ca
Office:
(519) 661-2111 ext. 86319
Expert In
Bio/Research
Our main research interest is directed towards addressing fundamental aspects of interfacial organic reactions and utilize the knowledge gained to design and synthesize new materials and to demonstrate potential applications. Reactions of molecules in solution are supported by a well developed in...
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Bio/Research
Our main research interest is directed towards addressing fundamental aspects of interfacial organic reactions and utilize the knowledge gained to design and synthesize new materials and to demonstrate potential applications. Reactions of molecules in solution are supported by a well developed intuition and set of methods from physical organic chemistry, but the reactions of molecules at the solid-liquid or solid-solid interface are not as well understood because they often behave in ways that are very different from those in solution. To investigate these differences, we design and synthesize photochemically, electrochemically and thermally responsive organic molecular systems to act as probes of the interactions in the interfacial environment of a variety of monolayer surfaces and to provide new platforms for selective surface modifications to build new architectures. A cornerstone of our efforts focuses on metal surfaces including self-assembled 2D monolayers and monolayer protected gold nanoparticles, and the proposal extends these reactions to investigate reactivity on other metallic nanoparticles and other relevant material solid surfaces.
The importance and motivation behind these studies lies in the recognition of the utility of organic thin films on functional materials in the development of molecular and biomolecular electronics, sensors, catalysis and other applications. Currently, progress towards application is not always based on clear understanding of the fundamental factors that control surface reactivity and molecular interactions in these unique assemblies. We are addressing these issues by examining photoinduced, redox activated and thermal reactivity in terms of chemical properties (structure-reactivity relationships, conformational and orientation mobility) and physical properties (structure, order-disorder phenomena, reaction conditions). In many cases the photoactive or electroactive moiety also serves as an analytical sensor/reporter of the chemistry. A complete understanding of these factors is essential for the rationale design and control of any modified surface for a particular application. Our current studies have revealed several mechanistic factors that are important and unique to interfacial reactions that have no counterpart in solution reactions and will continue to do so with novel reactive systems and the proposal expands the scope of our studies to other types of surfaces, including other noble metal and magnetic nanoparticles, carbon nanotubes, graphene, micro-diamond, fabrics and glass. Our next challenges are to utilize our probes to better control the reactivity and structure of these metal surfaces and nanoparticles, to develop new reactive probes activate photo- or electrochemically, and to use the reactions we developing for the controlled chemical modification of the suite of functional materials.
Another key area of interest is the study of the reactions of radical ions (charged species formed when a neutral organic molecule gains or loses a single electron). The reactivity of these radical anion and radical cation intermediates is relevant in all areas of chemistry and biochemistry. We are one of only a few groups in Canada who use organic electrochemistry for studies of reaction mechanisms. Our capability to combine both the electrochemical and photochemical methods facilitates the generation and study of the kinetics and thermodynamics of the reactions of radical ions that are important in biological and material applications.
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The importance and motivation behind these studies lies in the recognition of the utility of organic thin films on functional materials in the development of molecular and biomolecular electronics, sensors, catalysis and other applications. Currently, progress towards application is not always based on clear understanding of the fundamental factors that control surface reactivity and molecular interactions in these unique assemblies. We are addressing these issues by examining photoinduced, redox activated and thermal reactivity in terms of chemical properties (structure-reactivity relationships, conformational and orientation mobility) and physical properties (structure, order-disorder phenomena, reaction conditions). In many cases the photoactive or electroactive moiety also serves as an analytical sensor/reporter of the chemistry. A complete understanding of these factors is essential for the rationale design and control of any modified surface for a particular application. Our current studies have revealed several mechanistic factors that are important and unique to interfacial reactions that have no counterpart in solution reactions and will continue to do so with novel reactive systems and the proposal expands the scope of our studies to other types of surfaces, including other noble metal and magnetic nanoparticles, carbon nanotubes, graphene, micro-diamond, fabrics and glass. Our next challenges are to utilize our probes to better control the reactivity and structure of these metal surfaces and nanoparticles, to develop new reactive probes activate photo- or electrochemically, and to use the reactions we developing for the controlled chemical modification of the suite of functional materials.
Another key area of interest is the study of the reactions of radical ions (charged species formed when a neutral organic molecule gains or loses a single electron). The reactivity of these radical anion and radical cation intermediates is relevant in all areas of chemistry and biochemistry. We are one of only a few groups in Canada who use organic electrochemistry for studies of reaction mechanisms. Our capability to combine both the electrochemical and photochemical methods facilitates the generation and study of the kinetics and thermodynamics of the reactions of radical ions that are important in biological and material applications.
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