La2O3/Fe2O3-CeO2 Composite Oxide Catalyst and Its Performance ()
ABSTRACT
The La2O3/Fe2O3-CeO2 composite oxide catalysts were prepared by coprecipitation method, sol-gel method
and hydrothermal method. The effect of preparation methods on structure morphology
and photocatalytic properties of La2O3/Fe2O3-CeO2 samples was investigated. The results show that the cubic CeO2 structure
can be obtained at 600℃. The rod-shaped sample prepared by coprecipitation method,
displays the highest crystalline and the strongest diffraction peak intensity. The
spherical sample is acquired from sol-gel method, while the small granular sample
prepared by hydrothermal method tends to aggregate. The maximum specific surface
area of the sample prepared by coprecipitation method is 76.21 m2/g,
the minimum specific area of the sample from sol-gel method is 32.66 m2/g
and the maximum pore size is 13.84 nm, while the minimum pore volume and pore size
of the sample by hydrothermal method are 0.038 cm3/g and 3.95 nm respectively.
The band gap energy of catalyst samples is in the following order: sample-CP <
sample-SG < sample-HT. The sample obtained by coprecipitation method has the
best catalytic degradation performance for methylene blue. Under the excitation
of visible light, the degradation rate was 99.58% at 50 minutes, which was higher
than those of sol-gel method and hydrothermal method by 5.58% and 9.54% respectively.
The catalytic degradation reaction is a first-order kinetic model: ln (c0/ct) = kt + qe. The maximum k-value of the sample degradation process obtained by coprecipitation method
is 0.074 min-1.
Share and Cite:
Li, Y. , Lin, J. and Wang, G. (2019) La
2O
3/Fe
2O
3-CeO
2 Composite Oxide Catalyst and Its Performance.
Advances in Materials Physics and Chemistry,
9, 219-233. doi:
10.4236/ampc.2019.912017.