Study On Pyroelectric Photocatalytic Performance Of Tourmaline And Its Composite Photocatalyst

At present,environmental protection and energy issues are becoming more and more serious.Photocatalysis and pyroelectric catalytic technology are clean and environmentally friendly new catalytic technologies,and they have extremely bright application prospects.Tourmaline is a natural mineral material with pyroelectric properties.Both Ag₂O and BiOI are photocatalysts with good performance.Combining pyroelectrics and photocatalysts to prepare multifunctional materials can not only improve the catalytic efficiency,but also study photocatalysis.The relationship with pyroelectric catalysis.For this reason,a series of tourmaline and its composite materials with different particle sizes were prepared in this paper,and the photocatalytic performance and pyroelectric catalytic performance were studied.The main contents are as follows:（1）Prepare Ag₂O/tourmaline composite material by co-precipitation method Ag₂O is evenly distributed on the surface of tourmaline,effectively preventing its agglomeration.The photocatalytic test shows that the optimal composite ratio is Ag₂O:tourmaline=1:10（A/T-10）.The load of tourmaline improves the dispersion of Ag₂O and enhances the separation efficiency of photogenerated electrons and holes.Improve photocatalytic performance.（2）Prepare a variety of tourmaline materials with different particle sizes by ball milling,and test their catalytic performance.SEM characterization found that ball milling had a significant effect on the morphology of tourmaline,and the average particle size change was proved by Zeta potentiometer.The particle size of the ball-milled tourmaline is reduced and the specific surface area is increased.Through the pyroelectric catalytic degradation test,it is found that the increase of the specific surface area does not improve its pyroelectric performance.This may be due to the increase in the turning resistance of the electric dipole due to the smashing of the tourmaline,which reduces the spontaneous polarization and pyroelectric performance of the tourmaline.（3）BiOI/tourmaline composite materials were also prepared by precipitation method,and the relationship between photocatalysis and pyroelectric catalytic performance was studied.Like the Ag₂O/tourmaline composite material,the load of tourmaline also improves the dispersion of BiOI and the efficiency of photogenerated electron-hole separation.Through the comparison of photocatalysis,pyroelectric electrocatalysis,and pyroelectric photocatalytic degradation of tetracycline hydrochloride,it was found that the composite ratio of BiOI:tourmaline=1:2（B/T-0.5）performed best in the three experiments.By comparing the first-order degradation kinetics and degradation rate constants,it is found that the degradation rate of pyroelectric photocatalysis is greater than the sum of the degradation rates of pyroelectric catalysis,indicating that photocatalysis and pyroelectric catalysis have a synergistic effect,then discussed the mechanism of the synergistic effect of them.