A5038515823- Catalytic Processes in Materials Science
- Advanced Photocatalysis Techniques
- Gold and Silver Nanoparticles Synthesis and Applications
- Nanomaterials for catalytic reactions
- Oxidative Organic Chemistry Reactions
- Chemical Synthesis and Reactions
- Electrocatalysts for Energy Conversion
- Photochromic and Fluorescence Chemistry
- Mesoporous Materials and Catalysis
- Nanocluster Synthesis and Applications
- Advanced Nanomaterials in Catalysis
- Sulfur-Based Synthesis Techniques
- Synthetic Organic Chemistry Methods
- Lignin and Wood Chemistry
- Polyoxometalates: Synthesis and Applications
- Marine Toxins and Detection Methods
- Nanofabrication and Lithography Techniques
- Enzyme-mediated dye degradation
- Advanced biosensing and bioanalysis techniques
- Photochemistry and Electron Transfer Studies
- Catalysis and Oxidation Reactions
- Advancements in Photolithography Techniques
- Zeolite Catalysis and Synthesis
- Perovskite Materials and Applications
- Nonlinear Optical Materials Studies
St. Francis Xavier University
2014-2025
University of Ottawa
2011-2024
St Martha's Regional Hospital
2017-2018
Institute of Catalysis and Petrochemistry
2014
Centre for Catalysis Research and Innovation
2014
Parc Científic de la Universitat de València
2013
Universitat de València
2013
Dalhousie University
2008-2011
The Norrish type I photocleavage is an excellent source of strongly reducing free radicals that can be used to convert soluble metal ions into their atomic state proceed form nanoparticles. Proton coupled electron transfer (PCeT) a useful tool interpret the mechanism for ion reduction, process in these systems involves multisite PCeT, with proton and having separate receiving substrates.
Surface plasmon excitation of aqueous colloidal gold nanoparticles with visible light in the presence H2O2 led to rapid and selective oxidation sec-phenethyl benzyl alcohols acetophenone benzaldehyde, respectively. Laser drop, emitting diode, microwave irradiation have been used as energy sources. Interestingly, alcohol conversion was calculated be 95% 20 min when monochromatic 530 nm LEDs were used, being good or better yield than corresponding laser techniques. These results demonstrate...
Ablated, "pseudo-naked" gold nanoparticles (AuNPs) catalyze the cis–trans isomerization of substituted azobenzenes. para-Substitution was found to affect rate isomerization, suggesting participation AuNP-mediated electron transfer in mechanism.
Surface plasmon excitation of gold nanoparticles on ZnO in the presence an aldehyde, amine and phenylacetylene led to rapid selective formation propargylamines with good yields (50–95%) at room temperature. Plasmon mediated catalysis is best available route for this ternary coupling.
Several forms of niobium oxide were prepared, including nanostructured mesoporous materials, and their acidity properties comprehensively investigated compared with commercially available materials. The composites characterized by a variety techniques, XRD, TEM, N2 adsorption Hammett acid indicator studies. the derivatives was also ability materials to successfully promote halochromic ring-opening an oxazine-coumarin probe that specifically designed for use in fluorescence imaging reaction...
Surface plasmon excitation of supported gold nanoparticles in the presence H2O2 leads to selective oxidation sec-phenethyl and benzyl alcohols carbonyl products acetophenone benzaldehyde, respectively, absence additional solvents. Light-emitting diodes are compared with microwave irradiation as sources. Hydrotalcite, ZnO, Al2O3 have been chosen solid supports. The overall efficiency alcohol was found be largely dependent on nature support, hydrotalcite-derived nanocomposites giving highest...
Allergen-specific immunotherapy represents the only method of achieving a lasting reduction in severity allergic symptoms. However, need to expose patients allergens which they are sensitized carries risks. One solution is use denatured whereby structure allergenic proteins disrupted, preventing their recognition by immunoglobulin E (IgE) antibodies and thus reducing risk adverse reactions. Denaturation often carried out using chemical cross-linking generate allergoids. Gold nanoclusters...
The ketone-photoinduced formation of Au, Ag, and Cu nanoparticles from their corresponding ions in solution has been carried out using benzoin photoinitiators. Ketones are good photosensitizers for nanoparticle synthesis not because the energy they can absorb or deliver, but rather reducing free radicals generate. Efficient photochemical generation thus requires a careful selection substrates experimental conditions such that radical occurs with high quantum efficiency, where metal ion...
Lamellar, or layered, potassium niobium oxide perovskites are a class of underdeveloped semiconductors in organic photocatalysis that offer the inherent advantages larger particle size and ease recoverability as compared to traditional semiconductor materials.
Due to the considerable industrial implications, an in-depth study of cumene peroxidation using supported gold and silver nanoparticles was carried out gain more insight into mechanism this reaction. Supported were found efficiently catalyze decomposition hydroperoxide with a selectivity 25% at 80 °C when on hydrotalcite (AuNP@HT), 2-phenyl-2-propanol (i.e., cumyl alcohol) main product. Further, (AgNP@HT) converted 80% selectivity. Both benchtop oxygen-uptake experiments used probe reaction...
Samarium oxide nanoparticles (Sm<sub>2</sub>O<sub>3</sub>NP) were prepared photochemically for the first time.
Novel gold nanoparticle@niobium oxide perovskite composites promote the photoreduction of <italic>para</italic>-substituted nitroarenes, where electron-withdrawing groups accelerate photocatalytic reaction.
193 nm light as an excitation source for resist patterning is limited due to the inability achieve pitch division much below limits of λ/2. Current techniques are examining use a variety photochemical manipulations means extend lithographic small, more defined images. Double patterning, or dual tone lithography, has recently garnered considerable interest potential two features within one exposure. In this contribution, single component carbamate photoacid/photobase (PAG/PBG) generators...
Solid niobium oxides (Nb<sub>2</sub>O<sub>5</sub>·<italic>n</italic>H<sub>2</sub>O) and phosphate were used as heterogeneous acid catalysts to promote the condensation between a switchable oxazine fluorescent coumarin in aprotic solvents.
The development of quick and efficient methods for the detection pathogenic bacteria is urgently needed diagnosis infectious diseases control microbiological contamination in global waterways, potable water sources food industry. This contribution will describe synthesis gold nanoparticles their conjugation to broad spectrum, polypeptide β-lactam antibiotics that function as both reducing agents surface protectants (ATB@AuNP). Nanoparticle colloids examined using transmission electron...
The medicinal applications of noble metal nanomaterials are considerable interest due to the unique properties they possess. following contribution will showcase one these properties, photothermal effect produced by silver nanoparticles (AgNPs), and show how AgNPs can serve as potential viricidal materials for PPE (i.e., personal protective equipment) disinfection. In context COVID-19 global pandemic, disinfection is critical addressing shortfalls in supply chains that ensure rapid reliable...
Abstract A series of α ‐vinyl arylmethyl cations were generated and studied using nanosecond laser flash photolysis. Rate constants for the decay substituted determined under solvolytic conditions in pure solvents solvent mixtures 1,1,1,3,3,3‐hexafluoro‐2‐propanol (HFIP) 2,2,2‐trifluoroethanol (TFE). In addition absolute reactivity carbocations with added nucleophiles obtained. The reactivities then compared to corresponding ‐methyl, ‐phenyl, ‐cyclopropyl cations. Hammett σ + plots each...
<p>Several forms of niobium oxide were prepared, including nanostructured mesoporous materials, and their acidity properties comprehensively investigated compared with commercially available materials. The composites characterized by a variety techniques, XRD, TEM, N2 adsorption Hammett acid indicator studies. the derivatives was also ability materials to successfully promote halochromic ring-opening an oxazine-coumarin probe that specifically designed for use in fluorescence imaging...
Spherical gold nanoparticles have been supported onto the surface of potassium niobium oxide perovskites, an underdeveloped class semiconductor in photocatalytic organic transformations. The nanoparticle dopants 9.5 nm diameter and plasmon absorption at 530 are examined as possible visible light induced catalysts using alcohol photooxidation probe reaction. nanomaterial-induced a series aromatic alcohols is examined, absence solvent, function base, H 2 O , catalyst concentrations, well...
The size of photochemically-prepared niobium nanoparticles (NbNP) can be controlled by varying the concentration photoinitiator in reaction mixture. particles, which may metallic nature, are readily oxidized upon air exposure to form stable niobium(V) oxide (NbONP) that act as strong Brønsted acids.
Lignin is a promising renewable source of aromatic chemicals.
Solid niobium oxide treated with phosphoric acid (NbP) was used as a heterogeneous catalyst in the protection of series aliphatic alcohols tetrahydropyranyl (THP) derivatives. Protection primary using this material strong Brønsted sites achieved good yields (75%–94%), while moderate values were obtained secondary and tertiary (50%–84%), largely dependent on steric hindrance proximity hydroxyl moiety. NbP also catalyzed deprotection THP ethers derived from phenol (65%–99%).