Abstracts Book - IMRC 2018

• SWMC-P014
PHOTOCATALYTIC ACTIVITY OF STABILIZED β-Bi2O3 OBTAINED
FROM (BiO)4CO3(OH)2 PRECURSOR
Karen Valencia Garcia 1 , Agileo Hernández Gordillo 1 , Sandra Elizabeth Rodil 1 , Alejandro López
Guadarrama 1
1 Universidad Nacional Autónoma de México, Instituto de Investigaciones en Materiales,
Mexico.
Bi2O3 is considered as a good photocatalysts because can absorb in the visible
light. Generally, Bi2O3 has six polymorphs, among them, the low-temperature
ð•›¼−phase and the high temperature ð•›¿-phase are stable, while the other
phases are metastable. Among these phase structures, the α-, β- and ð•›¿-Bi2O3
polymorphs exhibit photocatalytic activity, however, the most active
heterogeneous photocatalyst is the β-phase [1,2], therefore, the fabrication of
β- Bi2O3 in phase-pure form is still great significance [3].Although the
nanocrystalline regimen of the materials is very important, since the
photocatalytic efficient depends on the size of agglomerate particles [4-5]. In this
work, β-Bi2O3 in nanometric regimen were prepared by annealing at 350-450°C
from two different precursors previously obtained by simple chemical
precipitation method. Ethylenediamine-solvent was used as precipitating and
capping agent. The influence of the relation HNO3/Bi on the physicochemical
properties and photocatalytic activity of stabilized β-Bi2O3 was investigated. The
characterization of the as prepared samples by X-ray diffraction which showed
that the crystalline structure of the dry material is completely amorphous, and
after of calcination process (at 350-450°C) β-Bi2O3 was successfully obtained.
The SEM analysis exhibits nano-flakes of the amorphous material of ~ 10 nm in
thickness, after the calcination process, the irregulars nanoparticles of ~ 80-500
nm of β-Bi2O3 are exhibited. The adsorption capacity in dark condition and the
photocatalytic activity under blue light (450 nm) of the stabilized β-Bi2O3 were
studied in the Indigo Carmine dye degradation.
References:
1. L.F. Yin, J.F. Niu, Z.Y. Shen, J. Chen, Environ. Sci. Technol. 44 (2010) 5581-
5586.
2. M. Schlesinger, S. Schulze, M. Hietschold, M. Mehring, Dalton Trans.
42(2013) 1047-1056.