Stabilized beta-Bi2O3 nanoparticles from (BiO)(4)CO3(OH)(2) precursor and their photocatalytic properties under blue light
Por:
Valencia G. K., López A., Hernández-Gordillo A., Zanella R., Rodil S.E.
Publicada:
15 dic 2018
Ahead of Print:
1 ene 2018
Resumen:
Stabilized tetragonal Bi2O3 nanoparticles (beta-Bi2O3) were obtained by
annealing treatments of amorphous Bi-based precursors, obtained by
chemical precipitations, at temperatures between 350 and 450 degrees C.
The formation of the stabilized beta-Bi2O3 phase was possible by using
(BiO)(4)CO3(OH)(2) while other precursors such as amorphous bismuth
carbonate ((BiO)(2)CO3) and amorphous basic bismuth nitrate
(Bi6O6(OH)(2)(NO3)(4)center dot 2H(2)O) led to the formation of the
thermodynamically stable monoclinic alpha-Bi2O3 and Bi5O7NO3 phases. The
Bi-based precursors were prepared by the chemical precipitation method
at room temperature in ethylenediamine-solvent varying the HNO3/Bi3+
molar ratio (10, 26 and 56). The physicochemical properties of the three
as-prepared amorphous precursors and the formed-after-calcination
beta-Bi2O3, alpha-Bi2O3 and Bi5O7NO3 phases were analyzed by X-ray
diffraction, scanning electron microscopy, thermogravimetry, X-ray
photoelectron spectroscopy (XPS), FTIR analysis, diffuse reflectance
spectroscopy and surface area by BET method. The photocatalytic activity
of all annealed solids containing the (beta-Bi2O3 phase was tested in
the photodegradation of the indigo carmine (IC) dye under specific blue
light. A schematic diagram of the Bi2O3 phases obtained as a function of
the annealing conditions and initial amorphous precursor is proposed and
explained in terms of the amount of CO32-, NO3- and amine (ENH22+ double
left right arrow ENW+) ions present in each bismuth precursor.
Filiaciones:
Valencia G. K.:
Instituto de investigaciones en Materiales, Universidad Nacional Autónoma de México, Circuito Exterior SN, Ciudad Universitaria, Mexico City, Coyoacán CP 04510, Mexico
López A.:
Instituto de investigaciones en Materiales, Universidad Nacional Autónoma de México, Circuito Exterior SN, Ciudad Universitaria, Mexico City, Coyoacán CP 04510, Mexico
Hernández-Gordillo A.:
Instituto de investigaciones en Materiales, Universidad Nacional Autónoma de México, Circuito Exterior SN, Ciudad Universitaria, Mexico City, Coyoacán CP 04510, Mexico
Zanella R.:
Instituto de Ciencias Aplicadas y Tecnología, Universidad Nacional Autónoma de México, Circuito Exterior SN, Ciudad Universitaria, Mexico City, Coyoacán CP 04510, Mexico
Rodil S.E.:
Instituto de investigaciones en Materiales, Universidad Nacional Autónoma de México, Circuito Exterior SN, Ciudad Universitaria, Mexico City, Coyoacán CP 04510, Mexico
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