Affiliations: Department of Chemistry, Liaoning University, Shenyang
110036, China | Department of Environment, Liaoning University,
Shenyang 110036, China | Center of Analysis and Test, Liaoning University,
Shenyang 110036, China
Abstract: A new upconversion luminescence agent,
40CdF_2·60BaF_2·0.8Er_2O_3,
was synthesized and its fluorescent spectra were determined. This upconversion
luminescence agent can emit five upconversion fluorescent peaks shown in the
fluorescent spectra whose wavelengths are all below 387 nm under the excitation
of 488 nm visible light. This upconversion luminescence agent was mixed into
nano rutile TiO_2 powder by ultrasonic and boiling
dispersion and the novel doped nano TiO_2 photocatalyst
utilizing visible light was firstly prepared. The doped
TiO_2 powder was charactered by XRD and TEM and its
photocatalytic activity was tested through the photocatalytic degradation of
methyl orange as a model compound under the visible light irradiation emitted
by six three basic color lamps. In order to compare the photocatalytic
activities, the same experiment was carried out for undoped
TiO_2 powder. The degradation ratio of methyl orange in the
presence of doped nano TiO_2 powder reached 32.5% under
visible light irradiation at 20 h which was obviously higher than the
corresponding 1.64% in the presence of undoped nano TiO_2
powder, which indicate the upconversion luminescence agent prepared as dopant
can effectively turn visible lights to ultraviolet lights that are absorbed by
nano TiO_2 particles to produce the electron-cavity pairs.
All the results show that the nano rutile TiO_2 powder doped
with upconversion luminescence agent is a promising photocatalyst using
sunlight for treating the industry dye wastewater in great force.
