摘要
以钛酸丁酯为原料,通过溶胶-微波法对纳米TiO_2进行掺杂复合改性,提高纳米TiO_2的光催化性能。采用SEM、TEM、XRD、XPS等手段研究了煅烧温度对溶胶-凝胶法制备的纳米Tb/TiO_2复合颗粒的晶型、形貌及光催化性能的影响。结果表明:当煅烧温度为500℃时,纯纳米TiO_2降解率最优为50.2%,纳米Tb/TiO_2复合颗粒降解率最优为75.1%,此时稀土铽掺杂量为0.50%,晶粒尺寸为8.9nm左右,其光学性能明显提高。合适的煅烧温度和稀土掺杂量能有效的提高纳米TiO_2光催化性能。分析发现,稀土Tb的掺杂拓宽了TiO_2的光响应范围,延迟晶型转变,提高TiO_2的热稳定性,此外还能抑制TiO_2晶粒的生长;纳米Tb/TiO_2复合颗粒为纯锐钛矿相,随着煅烧温度的升高,纳米TiO_2团聚加剧,比表面积降低,锐钛矿相向金红石相转变,光催化活性降低。
The photocatalytic performance of nanometer TiO2 was improved by doping with nano-TiO2 by Sol-microwave method u -sing butyl titanate as raw material. The effects of calcination temperature on the crystal morphology, morphology and photocatalytic properties of nano-sized Tb/TiO2composite particles prepared by Sol-microwav method were studied by means of SEM,TEM,XRD and XPS. The results show that when the calcination temperature is 500 ,the degradation rate of pure nano-TiO2 is 50. 2% ,and the degradation rate of nano-Tb/TiO2 composite particles is 75. 1% , and the rare earth terbium doping content is 0. 5 0 % . At this time rare earth terbium doping amount of 0. 50% ,grain size of about 8 . 9nm,its optical performance was significantly improved It is also found that the doping of rare earth Tb broadens the photoreaction range of TiO2, delays the crystal transformation, improves the thermal stability of TiO2,and restrains the growth of TiO2 grains. The nano-Tb/TiO2 composite particles are pure anatase. As the calcination temperature rises,the agglomeration of nano-TiO2 increases,the specific surface area decreases,the anatase phase chan-ges to rutile phase,and the photocatalytic activity decreases. The appropriate calcination temperature and rare earth doping amount can effectively improve the photocatalytic performance of nano-TiO2.
出处
《化学研究与应用》
CSCD
北大核心
2017年第11期1751-1755,共5页
Chemical Research and Application
基金
"十三五"国家重点研发计划(2016YFC0700904)
