Carbon nanostructures in various forms and sizes, and with different speciation properties have been prepared from graphite by Liquid Phase – Pulsed Laser Ablation (LP-PLA) using a high frequency Nd:YAG laser. High energy densities and... more
Carbon nanostructures in various forms and sizes, and with different speciation properties have been prepared from graphite by Liquid Phase – Pulsed Laser Ablation (LP-PLA) using a high frequency Nd:YAG laser. High energy densities and pulse repetition frequencies of up to 10 kHz were used in this ablation process to produce carbon nanomaterials with unique chemical structures. Dynamic Light Scattering (DLS), micro-Raman and High-Resolution Transmission Electron Microscopy (HRTEM) were used to confirm the size distribution, morphology, chemical bonding, and crystallinity of these nanostructures. This article demonstrates how the fabrication process affects measured characteristics of the produced carbon nanomaterials. The obtained particle properties have potential use for various applications including biochemical speciation applications.
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In this work, we demonstrate doping graphene oxide (GO) films using a low power atmospheric pressure plasma jet (APPJ) with subsequent tuning of the work function.
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The novel thiourea-functionalized silicon nanoparticles (SiNPs) have been successfully synthesized using allylamine and sulforaphane, an important anticancer drug, followed by a hydrosilylation reaction on the surface of hydrogen... more
The novel thiourea-functionalized silicon nanoparticles (SiNPs) have been successfully synthesized using allylamine and sulforaphane, an important anticancer drug, followed by a hydrosilylation reaction on the surface of hydrogen terminated SiNPs. Their physiochemical properties have been investigated by photoluminescence emission, FTIR and elemental analysis. MTT assay has been employed to evaluate in vitro toxicity in colorectal cancer cells (Caco-2) and primary normal cells (CCD). The results show significant toxicity of thiourea SiNPs after 72 h incubation in the cancer cell line and the toxicity is concentration dependent and saturated for concentrations above 100 µg/mL. Confocal microscopy images have demon-strated the internalization of thiourea-functionalized SiNPs inside the cells. Flow cytometry data has confirmed receptor-mediated targeting in cancer cells. This nanocomposite takes advantage of the EGFR active targeting of the ligand in addi-tion to the photoluminescence ...
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Electroactive biofilms are capable of extracellular electron transfer to insoluble metal oxides and electrodes; such biofilms are relevant to biogeochemistry, bioremediation, and bioelectricity production. We investigated the... more
Electroactive biofilms are capable of extracellular electron transfer to insoluble metal oxides and electrodes; such biofilms are relevant to biogeochemistry, bioremediation, and bioelectricity production. We investigated the extracellular electron transfer mechanisms in Shewanella loihica PV-4 viable biofilms grown at indium tin oxide (ITO) and graphite electrodes in potentiostat-controlled electrochemical cells poised at 0.2 V vs. Ag/AgCl. Chronoamperometry and confocal microscopy showed higher biofilm growth at graphite compared to the ITO electrode. Cyclic voltammetry, differential pulse voltammetry, along with fluorescence spectroscopy showed that direct electron transfer through outer membrane c type cytochromes (Omcs) prevailed at the biofilm/ITO interface, while biofilms formed at graphite electrode reduced the electrode also via secreted redox mediators, such as flavins and quinones. The biofilm age does not affect the prevalent transfer mechanism at ITO electrodes. On the ...
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... Arrow indicates the non substitutional Mn in 20% Mn doped GaN 4 Conclusions In conclusion we used XES and XAS to study the local electronic structure around Mn and N in GaMnN. ... PRTLI programme. JMD Coey is supported by Science... more
... Arrow indicates the non substitutional Mn in 20% Mn doped GaN 4 Conclusions In conclusion we used XES and XAS to study the local electronic structure around Mn and N in GaMnN. ... PRTLI programme. JMD Coey is supported by Science Founda-tion Ireland. ...
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Unique porous carbon monoliths containing thermally annealed carbon onions, were prepared from a resorcinol formaldehyde precursor rod, containing silica gel acting as a hard template, detonation nanodiamond, and Fe 3+ as a graphitisation... more
Unique porous carbon monoliths containing thermally annealed carbon onions, were prepared from a resorcinol formaldehyde precursor rod, containing silica gel acting as a hard template, detonation nanodiamond, and Fe 3+ as a graphitisation catalyst. Detonation nanodiamond was converted to carbon onions during controlled pyrolysis under N 2 , where the temperature cycle reached a maximum of 1250 C. Thermal characterisation and high resolution electron microscopy have confirmed the graphitisation of nanodiamond, and revealed the resulting quasi-spherical carbon onions with an average particle size of 5.24 nm. The bimodal porous composite contains both macropores (5 mm) and mesopores (10 nm), with a BET surface area of 214 m 2 g À1 for a nanodiamond prepared monolith (0.012 wt% nanodiamond in the precursor mixture), approximately twice that of blank monoliths, formed without the addition of nanodiamond, thus providing a new approach to increase surface area of such porous carbon rods. Raman spectroscopy and X-ray photoelectron spectroscopy also confirmed an enhanced graphitisation of the monolithic carbon skeleton resulting from the elevated thermal conductivity of the added nanodiamond. TEM imaging has confirmed the nanodiamond remains intact following pyrolysis at temperatures up to 900 C.