2016 |
Silva, N; Munoz, C; Diaz-Marcos, J; Samitier, J; Yutronic, N; Kogan, M J; Jara, P In Situ Visualization of the Local Photothermal Effect Produced on Alpha-Cyclodextrin Inclusion Compound Associated with Gold Nanoparticles Artículo de revista Nanoscale Research Letters, 11 , pp. 1-8, 2016, ISSN: 1556-276x. Resumen | Enlaces | BibTeX | Etiquetas: compound, cyclodextrin gold guest heating, inclusion metal migration, monolayers, nanoparticles, nanorods, nanotechnology, optical-properties, plasmonic therapy @article{RN300, title = {In Situ Visualization of the Local Photothermal Effect Produced on Alpha-Cyclodextrin Inclusion Compound Associated with Gold Nanoparticles}, author = { N. Silva and C. Munoz and J. Diaz-Marcos and J. Samitier and N. Yutronic and M.J. Kogan and P. Jara}, url = {/brokenurl#<Go to ISI>://WOS:000373961200001}, doi = {10.1186/s11671-016-1322-z}, issn = {1556-276x}, year = {2016}, date = {2016-01-01}, journal = {Nanoscale Research Letters}, volume = {11}, pages = {1-8}, abstract = {Evidence of guest migration in alpha-cyclodextrin-octylamine (alpha-CD-OA) inclusion compound (IC) generated via plasmonic heating of gold nanoparticles (AuNPs) has been studied. In this report, we demonstrate local effects generated by laser-mediated irradiation of a sample of AuNPs covered with inclusion compounds on surface-derivatized glass under liquid conditions by atomic force microscopy (AFM). Functionalized AuNPs on the glass and covered by the ICs were monitored by recording images by AFM during 5 h of irradiation, and images showed that after irradiation, a drastic decrease in the height of the AuNPs occurred. The absorption spectrum of the irradiated sample showed a hypsochromic shift from 542 to 536 nm, evidence suggesting that much of the population of nanoparticles lost all of the parts of the overlay of ICs due to the plasmonic heat generated by the irradiation. Mass spectrometry matrix-assisted laser desorption/ionization-time-of-flight (MALDI-TOF) performed on a sample containing a collection of drops obtained from the surface of the functionalized glass provided evidence that the irradiation lead to disintegration of the ICs and therefore exit of the octylamine molecule (the guest) from the cyclodextrin cavity (the matrix).}, keywords = {compound, cyclodextrin gold guest heating, inclusion metal migration, monolayers, nanoparticles, nanorods, nanotechnology, optical-properties, plasmonic therapy}, pubstate = {published}, tppubtype = {article} } Evidence of guest migration in alpha-cyclodextrin-octylamine (alpha-CD-OA) inclusion compound (IC) generated via plasmonic heating of gold nanoparticles (AuNPs) has been studied. In this report, we demonstrate local effects generated by laser-mediated irradiation of a sample of AuNPs covered with inclusion compounds on surface-derivatized glass under liquid conditions by atomic force microscopy (AFM). Functionalized AuNPs on the glass and covered by the ICs were monitored by recording images by AFM during 5 h of irradiation, and images showed that after irradiation, a drastic decrease in the height of the AuNPs occurred. The absorption spectrum of the irradiated sample showed a hypsochromic shift from 542 to 536 nm, evidence suggesting that much of the population of nanoparticles lost all of the parts of the overlay of ICs due to the plasmonic heat generated by the irradiation. Mass spectrometry matrix-assisted laser desorption/ionization-time-of-flight (MALDI-TOF) performed on a sample containing a collection of drops obtained from the surface of the functionalized glass provided evidence that the irradiation lead to disintegration of the ICs and therefore exit of the octylamine molecule (the guest) from the cyclodextrin cavity (the matrix). |
Castillo, C; Buono-Core, G; Manzur, C; Yutronic, N; Sierpe, R; Cabello, G; Chornik, B Molybdenum Trioxide Thin Films Doped with Gold Nanoparticles Grown by a Sequential Methodology: Photochemical Metal-Organic Deposition (Pmod) and Dc-Magnetron Sputtering Artículo de revista Journal of the Chilean Chemical Society, 61 (1), pp. 2816-2820, 2016, ISSN: 0717-9707. Resumen | Enlaces | BibTeX | Etiquetas: catalysis, diffraction, films, moo3, nanostructures, optical-properties, oxidation, oxide-films, oxides, photoelectron resonance, selective size, spectroscopy, sputtering, support, surface-plasmon temperature, thin x-ray xps @article{RN302, title = {Molybdenum Trioxide Thin Films Doped with Gold Nanoparticles Grown by a Sequential Methodology: Photochemical Metal-Organic Deposition (Pmod) and Dc-Magnetron Sputtering}, author = { C. Castillo and G. Buono-Core and C. Manzur and N. Yutronic and R. Sierpe and G. Cabello and B. Chornik}, url = {/brokenurl#<Go to ISI>://WOS:000378145500014}, doi = {10.4067/S0717-97072016000100014}, issn = {0717-9707}, year = {2016}, date = {2016-01-01}, journal = {Journal of the Chilean Chemical Society}, volume = {61}, number = {1}, pages = {2816-2820}, abstract = {Gold nanoparticles (AuNPs) were deposited by DC-magnetron sputtering onto molybdenum trioxide (MoO3) thin films grown by Photochemical Metal-Organic Deposition (PMOD) on Si(100) and borosilicate glass substrates. The chemical, optical and morphology properties of the films were studied by UV/Vis Spectroscopy, Scanning Electron Microscopy (SEM), X-Ray Photoelectron Spectroscopy (XPS), and X-Ray Diffraction (XRD). SEM revealed that AuNPs formed after 5 s of sputtering. AuNPs are spherical and have both an average diameter of 18 nm and a relatively narrow size distribution. As the deposition time increases, larger structures are formed by an aggregation of AuNPs. XPS studies of the AuNP/MoO3 films on Si(100) showed the presence of Mo(VI) and Mo(V), which indicated that the films were primarily non-stoichiometric molybdenum oxides. The occurrence of oxygen vacancies in the substrate play an important role to stabilize the AuNPs.}, keywords = {catalysis, diffraction, films, moo3, nanostructures, optical-properties, oxidation, oxide-films, oxides, photoelectron resonance, selective size, spectroscopy, sputtering, support, surface-plasmon temperature, thin x-ray xps}, pubstate = {published}, tppubtype = {article} } Gold nanoparticles (AuNPs) were deposited by DC-magnetron sputtering onto molybdenum trioxide (MoO3) thin films grown by Photochemical Metal-Organic Deposition (PMOD) on Si(100) and borosilicate glass substrates. The chemical, optical and morphology properties of the films were studied by UV/Vis Spectroscopy, Scanning Electron Microscopy (SEM), X-Ray Photoelectron Spectroscopy (XPS), and X-Ray Diffraction (XRD). SEM revealed that AuNPs formed after 5 s of sputtering. AuNPs are spherical and have both an average diameter of 18 nm and a relatively narrow size distribution. As the deposition time increases, larger structures are formed by an aggregation of AuNPs. XPS studies of the AuNP/MoO3 films on Si(100) showed the presence of Mo(VI) and Mo(V), which indicated that the films were primarily non-stoichiometric molybdenum oxides. The occurrence of oxygen vacancies in the substrate play an important role to stabilize the AuNPs. |
2015 |
Diaz, C; Barrera, G; Segovia, M; Valenzuela, M L; Osiak, M; O'dwyer, C Crystallizing Vanadium Pentoxide Nanostructures in the Solid-State Using Modified Block Copolymer and Chitosan Complexes Artículo de revista Journal of Nanomaterials, 10.1155/2015/105157 , 2015, ISSN: 1687-4110. Resumen | Enlaces | BibTeX | Etiquetas: electrochemical gold growth, intercalation, mechanisms, nanocomposites, nanoparticles, optical-properties, photoluminescence, precursors, properties, ruthenium @article{RN255, title = {Crystallizing Vanadium Pentoxide Nanostructures in the Solid-State Using Modified Block Copolymer and Chitosan Complexes}, author = { C. Diaz and G. Barrera and M. Segovia and M.L. Valenzuela and M. Osiak and C. O'dwyer}, url = {/brokenurl#<Go to ISI>://WOS:000354681800001}, doi = {10.1155/2015/105157}, issn = {1687-4110}, year = {2015}, date = {2015-01-01}, journal = {Journal of Nanomaterials}, volume = {10.1155/2015/105157}, abstract = {A systematic study of the synthesis of V2O5 nanostructured materials using macromolecular PS-co-4-PVP center dot(VCl3)(y) and chitosan center dot(VCl3)(y) complexes is presented. It is demonstrated that various coordination degrees of the metal into the polymeric chain specifically influence the product formation after pyrolysis. PS-co-4-PVP center dot(VCl3)(y) and chitosan center dot(VCl3)(y) complexes were prepared by simple coordination reaction of VCl3 with the respective polymer inmolar ratios 1 : 1, 1 : 5, and 1 : 10 metal/polymer and characterized by elemental analysis, IR spectroscopy, and TGA/DSC analysis. Solid-state thermolysis of these precursors at several temperatures under air results in nanostructured V2O5 using all precursors. The size and shape of the nanostructured V2O5 depend on the nature of the polymer. For the chitosan center dot(VCl3)(y) precursors sub-10nm nanocrystals are formed. The calcination process, involved in the preparation method, produces V2O5 with photoluminescence in the visible light region, suggesting the possible application in oxygen sensing devices.}, keywords = {electrochemical gold growth, intercalation, mechanisms, nanocomposites, nanoparticles, optical-properties, photoluminescence, precursors, properties, ruthenium}, pubstate = {published}, tppubtype = {article} } A systematic study of the synthesis of V2O5 nanostructured materials using macromolecular PS-co-4-PVP center dot(VCl3)(y) and chitosan center dot(VCl3)(y) complexes is presented. It is demonstrated that various coordination degrees of the metal into the polymeric chain specifically influence the product formation after pyrolysis. PS-co-4-PVP center dot(VCl3)(y) and chitosan center dot(VCl3)(y) complexes were prepared by simple coordination reaction of VCl3 with the respective polymer inmolar ratios 1 : 1, 1 : 5, and 1 : 10 metal/polymer and characterized by elemental analysis, IR spectroscopy, and TGA/DSC analysis. Solid-state thermolysis of these precursors at several temperatures under air results in nanostructured V2O5 using all precursors. The size and shape of the nanostructured V2O5 depend on the nature of the polymer. For the chitosan center dot(VCl3)(y) precursors sub-10nm nanocrystals are formed. The calcination process, involved in the preparation method, produces V2O5 with photoluminescence in the visible light region, suggesting the possible application in oxygen sensing devices. |
Silva, N; Arellano, E; Castro, C; Yutronic, N; Lang, E; Chornik, B; Jara, P Cyclodextrin Inclusion Compound Crystals for Growth of Cu-Au Core-Shell Nanoparticles Artículo de revista Journal of Inclusion Phenomena and Macrocyclic Chemistry, 82 (3-4), pp. 497-504, 2015, ISSN: 1388-3127. Resumen | Enlaces | BibTeX | Etiquetas: alpha-cyclodextrin, complexes compound, copper core-shell decylamine, fabrication, gold inclusion nanoparticles, optical-properties, oxide, particles, phase-transfer, scattering @article{RN248, title = {Cyclodextrin Inclusion Compound Crystals for Growth of Cu-Au Core-Shell Nanoparticles}, author = { N. Silva and E. Arellano and C. Castro and N. Yutronic and E. Lang and B. Chornik and P. Jara}, url = {/brokenurl#<Go to ISI>://WOS:000357572400020}, doi = {10.1007/s10847-015-0531-x}, issn = {1388-3127}, year = {2015}, date = {2015-01-01}, journal = {Journal of Inclusion Phenomena and Macrocyclic Chemistry}, volume = {82}, number = {3-4}, pages = {497-504}, abstract = {The preparation and structural elucidation of the 2 alpha-cyclodextrin/decylamine inclusion compound (IC) by proton nuclear magnetic resonance, rotating frame overhauser effect spectroscopy and powder X-ray diffraction have been achieved. The IC microcrystals were used as a support for the preparation of Au-Cu core-shell nanoparticles by the sputtering method. The coating of copper nanoparticles with gold was verified through anodic stripping voltammetry. The presence of metallic copper and the absence of copper oxides were determined by X-ray photoelectron spectroscopy. These results show that the formation of core-shell Cu-Au by sputtering is an effective approach to prevent the oxidation of Cu particles, leading to potential applications in nanoelectronics.}, keywords = {alpha-cyclodextrin, complexes compound, copper core-shell decylamine, fabrication, gold inclusion nanoparticles, optical-properties, oxide, particles, phase-transfer, scattering}, pubstate = {published}, tppubtype = {article} } The preparation and structural elucidation of the 2 alpha-cyclodextrin/decylamine inclusion compound (IC) by proton nuclear magnetic resonance, rotating frame overhauser effect spectroscopy and powder X-ray diffraction have been achieved. The IC microcrystals were used as a support for the preparation of Au-Cu core-shell nanoparticles by the sputtering method. The coating of copper nanoparticles with gold was verified through anodic stripping voltammetry. The presence of metallic copper and the absence of copper oxides were determined by X-ray photoelectron spectroscopy. These results show that the formation of core-shell Cu-Au by sputtering is an effective approach to prevent the oxidation of Cu particles, leading to potential applications in nanoelectronics. |
2016 |
In Situ Visualization of the Local Photothermal Effect Produced on Alpha-Cyclodextrin Inclusion Compound Associated with Gold Nanoparticles Artículo de revista Nanoscale Research Letters, 11 , pp. 1-8, 2016, ISSN: 1556-276x. |
Molybdenum Trioxide Thin Films Doped with Gold Nanoparticles Grown by a Sequential Methodology: Photochemical Metal-Organic Deposition (Pmod) and Dc-Magnetron Sputtering Artículo de revista Journal of the Chilean Chemical Society, 61 (1), pp. 2816-2820, 2016, ISSN: 0717-9707. |
2015 |
Crystallizing Vanadium Pentoxide Nanostructures in the Solid-State Using Modified Block Copolymer and Chitosan Complexes Artículo de revista Journal of Nanomaterials, 10.1155/2015/105157 , 2015, ISSN: 1687-4110. |
Cyclodextrin Inclusion Compound Crystals for Growth of Cu-Au Core-Shell Nanoparticles Artículo de revista Journal of Inclusion Phenomena and Macrocyclic Chemistry, 82 (3-4), pp. 497-504, 2015, ISSN: 1388-3127. |