Resumo de eventos cient??ficos
Performance of nitrogen-doped TiO2 films grown by MOCVD for water treatment under visible light
Registro en:
0000-0002-1423-871X
0000-0002-1797-9652
Autor
OLIVEIRA, EDUARDO C. de
BENTO, RODRIGO T.
CORREA, OLANDIR V.
PILLIS, MARINA F.
E-MRS SPRING MEETING; IUMRS-ICAM INTERNATIONAL CONFERENCE ON ADVANCED MATERIALS
Resumen
Titanium dioxide is a semiconductor employed as catalyst in the photodegradation of organic
pollutants and bacteria. However, due to its large band gap TiO2 only can be excited by UV light.
Recently, TiO2 doping with metals or nonmetals elements has been extensively exploited to allow its
use under visible light. In the present work, nitrogen-doped and undoped TiO2 films were grown on
borosilicate substrates at 400 ?? C for 60 minutes by metallorganic chemical vapor deposition
(MOCVD). Titanium isopropoxide IV was used as precursor of titanium and oxygen, and ammonia
as nitrogen source. Ammonia was incorporated into the films in three different quantities during the
growth. The effect of nitrogen contents on the structural and surface properties of TiO2 catalysts was
evaluated. Both doped and undoped films presented rounded well-defined anatase grains. XPS
analyses revealed that values of 1.6; 2.4 and 7.3 at% of nitrogen were incorporated into the films by
varying the ammonia flux during the growth. Degradation assays have shown that nitrogen-doped
TiO2 films exhibited high photocatalytic activity under visible light irradiation. Undoped films did
not present activity in this condition. The better catalytic performance under visible light, 55% of dye
degradation, was attributed to the film containing 2.4 at% of nitrogen. The results suggest that
nitrogen-doped TiO2 catalysts grown by MOCVD have great potential to be used in the treatment of
water under sunlight.