Universidad Nacional Autónoma de México - CNyN

1st International Symposium on Nanoscience and Nanomaterials
Keywords: 4-nitrophenol, photodegradation, TiO 2 .
The photocatalytic degradation of 4 nitrophenol was investigated using the TiO 2 as catalyst. Different
concentrations of 4 nitrophenol were in use (20 to 200 ppm) used 0.2 g of catalyst for every 100 mL of
solution. The experiments were carried out in a reactor, which consistent of a cylinder constructed of stainless
steel in finished mirror, with 4 lamps of ultraviolet light (UV) of 15 watts (365 nm) and with agitation.
Samples of reaction took to certain intervals of time, the samples were leaked by means of a membrane
Millipore by a diameter of pore of 0.22 m. The taken samples were analyzed by means of a Uv-vis model
DR-5000 and for high perfomance liquid chromatography (HPLC) Agilent model 1 100. Some samples of
the degradation reaction of 4-nitrophenol was evaluated by UV-Vis spectroscop. These results did not detect
other signals that could be correlated to other species, for which only sees the decrease in the intensity of the
peak at 320 nm corresponding to the chemical degradation of the molecule of 4-nitrophenol. The times of
degradation was 300 minutes and observe that in average 90 % of conversion was obtained. Being observed
that the samples to low concentration had a behavior of agreement to a reaction of first order and those of
high concentration had a trend of order zero. I detect to him that after 90 minutes intermediary products
appeared, one of which was the hidroquinone. Observed
intermediary.
P-026
that after 90 minutes the turned out to be
SYNTHESIS OF MONO AND BIMETALLIC COLLOIDAL PARTICLES VIA MICROFLUIDIC
MIXER
Brenda Acosta R. 1,a , Viridiana Evangelista H. 1,b Miguel A. Estrada A. 1,c , Martín López C. 2,d , Andrey
Simakov 3,e .
1 Posgrado en Física de Materiales, Centro de Investigación Científica y de Educación Superior de Ensenada
(CICESE), Ensenada, B.C., 22860, México.
2 Posgrado en Ciencia e Ingeniería de Materiales, Universidad Nacional Autónoma de México (CNyN-
UNAM), Ensenada, BC, 22860, México.
3 Centro de Nanociencias y Nanotecnología, Universidad Nacional Autónoma de México (CNyN-UNAM),
Ensenada, BC, 22860, México.
a bracosta@cnyn.unam.mx, b vevangel@cnyn.unam.mx, c mestrada@cnyn.unam.mx,
d martinlopez@cnyn.unam.mx, e andrey@cnyn.unam.mx
Keywords: Bimetallic nanoparticles, microfluidic device, Au, Pd.
Nanoparticles have unique properties based on their sizes, shapes, morphology and composition.
Bimetallic nanoparticles, due to their bimetallization, can improve properties of the original single metal or
create new ones. The colloidal dispersions of bimetallic nanoparticles have some advantages, like the
elucidation without the effect of the metal support interaction, in comparison with the supported ones.
Microfluidic devices, designed to manipulate fluids in microchannels, have been developed to synthesize
nanoparticles with narrow size distribution. This abstract is focused in the mono (Au, Pd) and bimetallic (Au-
Pd) colloidal nanoparticles synthesis carried out by continuous laminar flow via microfluidic systems. The
characterization of the resulting nanoparticles was carried out by TEM and UV-Vis spectroscopy. According
TEM images, a narrow particle size distribution was obtained. The nanoparticles dynamic formation was
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