Article
Surface characterization of nanostructured TiO2 and carbon blacks composites by dye adsorption and photoelectrochemical studies
Fecha
2014Autor
Aguilar, J.
Moscoso, F.
Rios, O.
Ceja, I.
Sanchez, J.C.
Bautista, F.
Puig, J.E.
Fernandez, V.V.A.
Institución
Resumen
The synthesis of poly(N-isopropylacrylamide) nanogels by semi-continuous inverse heterophase polymerization (SIHP) under monomer starved conditions is reported here. This process consists in adding a N-isopropylacrylamide (NIPA) aqueous solution at a controlled rate over a monomer-free oleic solution containing surfactant and initiator. The nanogels became smaller with narrower size distributions as the addition rate was decreased. Moreover, nanogel sizes, the size distributions and more importantly, the polymer/surfactant ratios were smaller than those of PNIPA nanogels synthesized by batch inverse microemulsion polymerization (BIMP). The swelling behavior of these nanogels in water as a function of temperature is reported. As expected, all nanogels have a volume phase transition temperature at ca. 33-34°C. " 2014 Taylor & Francis Group, LLC.",,,,,,"10.1080/10601325.2014.893133",,,"http://hdl.handle.net/20.500.12104/44883","http://www.scopus.com/inward/record.url?eid=2-s2.0-84899478990&partnerID=40&md5=a78edf734ce777d03155d4a719a7a0e7",,,,,,"5",,"Journal of Macromolecular Science, Part A: Pure and Applied Chemistry",,"412 419",,"51",,"Scopus WOS",,,,,,"batch inverse microemulsion polymerization; Poly(N-isopropylacrylamide) nanogels; semi-continuous inverse heterophase polymerization",,,,,,"Swelling behavior of poly(N-isopropylacrylamide) nanogels with narrow size distribution made by semi-continuous inverse heterophase polymerization",,"Article"
"46635","123456789/35008",,"Rincón, M.E., Centro de Investigación en Energía-UNAM, Apartado Postal 34, Temixco, 62580 MOR, Mexico; Trujillo-Camacho, M.E., Centro de Investigación en Energía-UNAM, Apartado Postal 34, Temixco, 62580 MOR, Mexico; Cuentas-Gallegos, A.K., Centro de Investigación en Energía-UNAM, Apartado Postal 34, Temixco, 62580 MOR, Mexico; Casillas, N., Universidad de Guadalajara, Departamento de Química, Blvd. Marcelino García Barragan 1451, Guadalajara, Mexico CP 44430, Mexico",,"Rincon, M.E. Trujillo-Camacho, M.E. Cuentas-Gallegos, A.K. Casillas, N.",,"2006",,"Photocatalysts based on nanostructured TiO2 and carbon blacks (CB) particles were obtained by chemical (sol-gel) and physical (mechanical grinding) preparation techniques. Characterization of these samples by XRD, FT-IR and dye adsorption studies was combined with optical and scanning photoelectrochemical analysis in an attempt to explain the photodegradation efficiency of these materials. The superior adsorption of sol-gel materials in the aqueous dye solutions did not account for the differences observed in photocatalytic activity, where the sol-gel composite outperforms the physical mixture or TiO2 alone by one digit. Data on the photoelectrochemical activity of these composites showed the abundance of inactive sites in the mixtures, while the sol-gel composite showed a uniform active surface. Rectification properties brought up by carbon in sol-gel composites and plus the abundance of hydroxyl groups on the oxide surface are proposed to be responsible for the long-term activity of these photocatalysts. " 2006 Elsevier B.V. All rights reserved.