A5037991675- Electrocatalysts for Energy Conversion
- Microbial Fuel Cells and Bioremediation
- Extraction and Separation Processes
- Nanomaterials for catalytic reactions
- Radioactive element chemistry and processing
- Environmental remediation with nanomaterials
- Catalysis for Biomass Conversion
- Electrochemical Analysis and Applications
- Chromium effects and bioremediation
- Catalysis and Hydrodesulfurization Studies
- Biofuel production and bioconversion
- Nanoparticles: synthesis and applications
- Metal Extraction and Bioleaching
- Geochemistry and Elemental Analysis
- Advanced NMR Techniques and Applications
- Asymmetric Hydrogenation and Catalysis
- Magnetic and Electromagnetic Effects
- Fuel Cells and Related Materials
- Microbial bioremediation and biosurfactants
- Bone Tissue Engineering Materials
- Catalytic Cross-Coupling Reactions
- Adsorption and biosorption for pollutant removal
- Innovative Microfluidic and Catalytic Techniques Innovation
- Chemical Reactions and Isotopes
- Gold and Silver Nanoparticles Synthesis and Applications
University of Birmingham
2011-2022
University of Wollongong
2007
Escherichia coli produces at least three [NiFe] hydrogenases (Hyd-1, Hyd-2 and Hyd-3). Hyd-1 are membrane-bound respiratory isoenzymes with their catalytic subunits exposed to the periplasmic side of membrane. Hyd-3 is part cytoplasmically oriented formate hydrogenlyase complex. In this work involvement each these in Pd(II) reduction under acidic (pH 2.4) conditions was studied. While all could contribute reduction, presence either hydrogenase (Hyd-1 or Hyd-2) required observe rates...
Escherichia coli can perform at least two modes of anaerobic hydrogen metabolism and expresses types hydrogenase activity. Respiratory oxidation is catalysed by 'uptake' isoenzymes, -1 -2 (Hyd-1 -2), fermentative production Hyd-3. Harnessing enhancing the metabolic capability E. to mixed-acid fermentation therefore an attractive approach for bio-hydrogen from sugars. In this work, effects genetic modification genes encoding uptake hydrogenases, as well importance preculture conditions, on...
Wild-type Desulfovibrio fructosivorans and three hydrogenase-negative mutants reduced Pd(II) to Pd(0). The location of Pd(0) nanoparticles on the cytoplasmic membrane mutant retaining only membrane-bound hydrogenase was strong evidence for role hydrogenases in deposition. Hydrogenase activity retained at acidic pH, shown previously favor
We report a novel biochemical method based on the sacrificial hydrogen strategy to synthesize bimetallic gold (Au)–palladium (Pd) nanoparticles (NPs) with core/shell configuration. The ability of Escherichia coli cells supplied H 2 as electron donor rapidly precipitate Pd(II) ions from solution is used promote reduction soluble Au(III). Pre-coating Pd(0) (bioPd) dramatically accelerated Au(III) reduction, rate being dependent upon initial Pd loading by mass cells. Following addition,...
Five gram negative and two positive bacterial strains known for their heavy metal tolerance or ability to reduce ions were coated with Pd(0) nanoparticles (NPs) via reduction of soluble Pd(II) under H2 following an initial uptake PdCl42- without added electron donor ('biosorption'), where the had a ~5-fold greater capacity Pd(II). Cupriavidis metallidurans accumulated exceptionally; possibility endogenous was not discounted. The rate subsequent H2-mediated correlated removed during...
Early studies have focused on the synthesis of palladium nanoparticles within periplasmic layer or outer membrane
Escherichia coli cells support the nucleation and growth of ruthenium ruthenium-palladium nanoparticles (Bio-Ru Bio-Pd/Ru NPs). We report a method for synthesis these monometallic bimetallic NPs their application in catalytic upgrading 5-hydroxymethyl furfural (5-HMF) to 2,5 dimethylfuran (DMF). Examination using high resolution transmission electron microscopy with energy dispersive X-ray microanalysis (EDX) angle annular dark field (HAADF) showed Ru located mainly at cell surface Ru(III)...
The Heck coupling of iodobenzene with ethyl acrylate or styrene was used to assess the catalytic properties biogenic nanoparticles palladium supported upon surface bacterial biomass (bioPd), this approach combining advantages both homogeneous and heterogeneous catalysts. biomaterial comparably active superior colloidal Pd in reaction, giving a final conversion 85% halide initial rate 0.17 mmol/min for compared 70% 0.15 catalyst under same reaction conditions at 0.5 mol.% loading. It easily...
Abstract Bacillus benzeovorans assisted and supported growth of ruthenium (bio-Ru) palladium/ruthenium (bio-Pd@Ru) core@shell nanoparticles (NPs) as bio-derived catalysts. Characterization the bio-NPs using various electron microscopy techniques high-angle annular dark field (HAADF) analysis confirmed two NP populations (1–2 nm 5–8 nm), with core@shells in latter. The Pd/Ru lattice fringes, 0.231 nm, corresponded to (110) plane RuO 2. While surface characterization X-ray photoelectron...
A hydrogen economy powered by fuel cells is emerging as an alternative to the current fossil-fuel based energy system where hydrogen, produced through renewable sources, used generate electricity via cells. commonly investigated cell, Polymer Electrolyte Fuel Cell (PEMFC), usually uses platinum and other group metal nanomaterials catalyze rate limiting Oxygen Reduction Reaction (ORR) of this process. The high prices durability limitations these catalysts have prevented their mass...
Numerous studies have focused on the bacterial synthesis of palladium nanoparticles (bio-Pd NPs), via uptake Pd (II) ions and their enzymatically-mediated reduction to (0). Cells Desulfovibrio desulfuricans (obligate anaerobe) Escherichia coli (facultative anaerobe, grown anaerobically) were exposed low-dose radiofrequency (RF) radiation(microwave (MW) energy) biosynthesized NPs compared. Resting cells microwave energy before (II)-challenge. MW-injured (II)-treated (and non MW-treated...
For the first time, method of shell-isolated nanoparticle Raman spectroscopy (SHINERS) is used in combination with cyclic voltammetry (CV) and reactivity studies to investigate adsorption behaviour a series three alkynes undergoing hydrogenation on nanoparticle, single crystal bacteria/graphite-supported platinum surfaces. It found that strong association defect sites produce long-lived di-sigma/pi-alkene surface complex allows for deep this intermediate alkane product. In contrast, when are...
Palladium bioinorganic catalyst (bio-Pd) was manufactured using bacteria (Desulfovibrio desulfuricans and Escherichia coli) via the reduction of Pd(II) to bio-scaffolded Pd(0) nanoparticles (NPs). The formed Pd NPs were examined electron microscopy X-ray powder diffraction methods: a loading 5 wt% showed an average particle size ∼4 nm. catalytic activities prepared bio-Pd on both compared in two hydrogenation reactions with that conventionally supported (Pd/Al2O3). Concentration profiles...
Bacterial hydrogenases have been harnessed to the removal of heavy metals from solution by reduction less soluble metal species. For Pd(II), its bioreduction results in deposition cell-bound Pd(0)-nanoparticles that are ferromagnetic and a high catalytic activity. Hydrogenases can also be used synthetically production hydrogen sugary wastes through breakdown formate produced fermentation. The Bio-H2 power an electrical device using fuel cell provide clean electricity. Production...
The use of bacterial flagella as templates for the immobilization Pd and Au nanoparticles is described. Complete coverage D. desulfuricans flagellar filaments by Pd(0) was obtained via H(2)-mediated reduction Pd(NH3)4]Cl2 but similar results were not using HAuCl4. introduction additional cysteine-derived thiol residues in E. coli FliC protein increased Au(III) sorption onto surface filament resulted production stabilized Au(0) approximately 20-50 nm diameter. We demonstrate application...
Abstract BACKGROUND: Desulfovibrio spp. biofabricate metallic nanoparticles (e.g. ‘Bio‐Pd’) which catalyse the reduction of Cr(VI) to Cr(III) and dehalogenate polychlorinated biphenyls (PCBs). are anaerobic produce H 2 S, a potent catalyst poison, whereas Escherichia coli can be pre‐grown aerobically high density, has well defined molecular tools, also makes catalytically‐active ‘Bio‐Pd’. The first aim was compare ‘Bio‐Pd’ catalysts made by E. using suspended immobilized catalysts. second...
Waste H<sub>2</sub>S biogas from a mine-water remediation bioprocess is used to make zinc sulfide quantum dots which are identical ZnS QDs made by chemical methods.