Please use this identifier to cite or link to this item:
|Title:||Thermal decomposition of diammonium tetrachloroplatinate to form platinum nanoparticles and its application as electrodes|
|Abstract:||In the present work semi-empirical PM3 method and ab initio density-functional theory calculations were performed in carbon systems. The condensed Fukui function was calculated and HOMO-LUMO were visualised in order to study the sequence of hydroxylation of two isomers of C82 fullerene for the low coverage regime, with the formula C82(OH) x where x = 0 - 12. It was found that there was a formation of dangling bonds on structures with an odd number of hydroxyl groups on the fullerene surface, which suggests an enhanced reactivity of these molecules. Nevertheless, the coverings with an even number of groups tend to the reconstruction of bonds, obtaining less reactive molecular structures. With the adsorption of the first group, a narrow HOMO-LUMO gap (1.28 eV) is observed in comparison with the C82(OH)2 system (1.70 eV), as is found in similar systems, such as C60 fullerenol [E.E. Fileti et al., Nanotechnology 19, 365703 (2008); J.G. Rodríguez-Zavala and R.A. Guirado-López, Phys. Rev. B 69, 075411 (2004)]. Through an analysis of the electronic structure to these coverings, a splitting of electronic energy levels in the structure with one hydroxyl group is observed, which could be one of the factors that causes the narrowing of the energy gap in this structure. On the other hand, with a coverage of 12 hydroxyl groups, the formation of an amphiphilic molecule, where the location of groups in one side of the C 82 surface provides an hydrophilic character, is observed, while the uncovered part has an hydrophobic character. This could be important in the formation of Langmuir monolayers. Finally, it is shown that the precise distribution of the OH groups on the fullerene surface plays a crucial role in the electronic structure of the polyhydroxylated fullerenes. " 2011 Taylor & Francis.",,,,,,"10.1080/00268976.2011.591743",,,"http://hdl.handle.net/20.500.12104/45332","http://www.scopus.com/inward/record.url?eid=2-s2.0-79960990960&partnerID=40&md5=33130695b3999c336d70e7450fbd0977",,,,,,"14",,"Molecular Physics",,"1771|
WOS",,,,,,"carbon system; fullerene; hydroxylation",,,,,,"Theoretical study on the sequential hydroxylation of C82 fullerene based on Fukui function",,"Article" "47120","123456789/35008",,"Soltero, J.F.A., Universidad de Guadalajara, Guadalajara, Mexico; Puig, J.E., Universidad de Guadalajara, Guadalajara, Mexico; Schulz, P.C., Universidad de Guadalajara, Guadalajara, Mexico",,"Soltero, J.F.A.
Schulz, P.C.",,"1998",,"The state of water and several transitions were examined in the systems n-decanephosphonic acid (DPA)-water and the sodium salts of DPA-water. Temperature - composition phase diagrams are reported. The results show that several liquid crystalline phases plus isotropic liquid, and two solid phases (a waxy solid phase and a crystalline phase) are formed. Several types of water were detected: bulk-like water, interfacial water and hydration water.",,,,,,,,,"http://hdl.handle.net/20.500.12104/45341","http://www.scopus.com/inward/record.url?eid=2-s2.0-0032293054&partnerID=40&md5=edb86ec000b85fca1a91263dca4cf207",,,,,,"1",,"Journal of Thermal Analysis and Calorimetry",,"105
WOS",,,,,,,,,,,,"Thermal transitions and state of water in binary mixtures of water and n-decanephosphonic acid or its sodium salts",,"Article" "47115","123456789/35008",,"Calderón, D.M., Depto. de Química, Universidad Autónoma Metropolitana Iztapalapa, San Rafael Atlixco 186, México, D.F., Mexico; Morales, U., Depto. de Química, Universidad Autónoma Metropolitana Iztapalapa, San Rafael Atlixco 186, México, D.F., Mexico; Velásquez, C., Departamento de Ciencias Naturales y Exactas, Centro Universitario de Los Valles, Universidad de Guadalajara, Carretera Guadalajara, Ameca, km. 45.5, Ameca, Jalisco C.P. 46600, Mexico; Lara, V.H., Depto. de Química, Universidad Autónoma Metropolitana Iztapalapa, San Rafael Atlixco 186, México, D.F., Mexico; Salgado, L., Depto. de Química, Universidad Autónoma Metropolitana Iztapalapa, San Rafael Atlixco 186, México, D.F., Mexico",,"Calderon, D.M.
Salgado, L.",,"2009",,"Pt nanoparticles were obtained via the thermal decomposition of (NH 4)2[PtCl4] (diammonium tetrachloroplatinate) by heating from room temperature to 760 °C. The thermal decomposition process was analyzed using thermogravimetric analysis (TGA) and differential thermal analysis (DTA), X-ray thermodiffraction and infrared spectroscopy. The size and structure of the platinum particles were analyzed using transmission electron microscopy (TEM). The electrochemical activity of Pt particles was assessed by cyclic voltammetry in 0.5 M H2SO4. The TGA and DTA results suggested that the thermal decomposition of the precursor proceeded in two stages: loss of NH4Cl at ?300 °C, followed by loss of NH 4Cl and Cl2 at ?372 °C. Metallic Pt particles were then produced at temperatures of 372 °C and above. At 760 °C, the mean SD size of the Pt particles was (4.1 1.6) nm, as determined from TEM measurements. In cyclic voltammetry (CV) measurements, an electrode comprised of glassy carbon and Pt particles in 0.5 M H2SO4 exhibited behavior similar to that observed using a polycrystalline Pt electrode. " 2009 Springer Science+Business Media, LLC.
|Appears in Collections:||Producción científica UdeG|
Files in This Item:
There are no files associated with this item.
Items in RIUdeG are protected by copyright, with all rights reserved, unless otherwise indicated.