Fabrication And Photocatalytic,Piezo-catalytic,Thermo-catalytic Study Of Ferroelectric Titanate Nano-materials

In oder to meet the need of environmental protection,the degradation of organic dye wastewater is imminent.Photocatalysis,as a main method of dye degradation,has been widely studied because of its unique advantages such as sanitation and safety.However,the development of traditional photocatalytic materials has been hindered because of the wide energy gap,thus the low efficiency of solar energy use and the high transmittance demand that cannot be applied in dark or in weak illumination circumstances.Therefore,it is very important to develop a new technology for the dye wastewater treatment.In this work,these catalytic activities of photocatalysis,piezo-catalysis and thermo-catalysis of ferroelectric titanate nano-materials have been studied under some different excitation sources(light irridation,vibration,thermal alternation).The main research results are listed as follows:(1)The visible-light photocatalytic activity of Bi0.5Na0.5TiO3 and Ba0.7Sr0.3TiO3 nano-materialsBi0.5Na0.5TiO3 and Ba0.7Sr0.3TiO3 nano-particles were sol-gel-synthesized via adopting the different temperatures and pH conditions,respectively.It is found that Bi0.5Na0.5TiO3 nano-particles with an addition mass of 1.0 g/L can degrade 95%Rhodamine B(5 mg/L)in 120 min under the visible-light irridation.Ba0.7Sr0.3TiO3 nano-particles with an addition mass of 1.0 g/L can degrade 57%of Rhodamine B(5 mg/L)in 8 h under the visible-light irridation.(See Charpter 3)(2)The piezo-catalytic activity of Bi0.5Na0.5TiO3 and Ba0.7Sr0.3TiO3 nano-materialsBi0.5Na0.5TiO3 and Ba0.7Sr0.3TiO3 nano-particles were sol-gel-synthesized via adopting the different temperatures and pH conditions,respectively.It is found that Bi0.5Na0.5TiO3 nano-particles with an addition mass of 1.0 g/L can degrade 96.2%of Rhodamine B(5 mg/L)in 5 h with the help of 1 vol%of H2O2 under vibration.Ba0.7Sr0.3TiO3 nano-particles with an addition mass of 1.0 g/L can degrade 68.5%Rhodamine B(5 mg/L)in 6 h under vibration.(See Charpter 4)(3)The thermo-catalytic activity of these Bi0.5Na0.5TiO3,Ba0.7Sr0.3TiO3 and Ba0.7Sr0.3TiO3@Ag ferroelectric nano-materialsBi0.5Na0.5TiO3 and Ba0.7Sr0.3TiO3 nano-particles were sol-gel-synthesized via adopting the different temperatures and pH conditions,respectively.Ba0.7Sr0.3TiO3@Ag nano-materials were synthesized via a photo-reduction method.It is found that Bi0.5Na0.5TiO3 nano-particles with an addition mass of 1.0 g/L can degrade 97.2%of Rhodamine B(5 mg/L)with the addition of 1 vol%of H2O2 after experiencing 95 cold-hot thermal cycles from 25 ? to 50?.Ba0.7Sr0.3TiO3 and Ba0.7Sr0.3TiO3@Ag nano-particles with an addition mass of 1.0 g/L can degrade 90%and 99%Rhodamine B(5 mg/L)after experiencing 50 cold-hot thermal cycles from 25 ? to 50 ?,respectively.(See Charpter5)...