溶胶-凝胶法制备TiO2纳米颗粒及其光催化性能

考察了通过溶胶-凝胶法进行过渡金属(Fe3 、Zn2 、Co2 、Ni2 、Cr3 和Sn4 )和稀土元素(La3 、Pr3 、Nd3 、Ce4 、Sm3 、Tb3 、Eu.3 、Gd3 、Y3 和Dy3 )掺杂的TiO2纳米颗粒的光催化活性,以及通过超声波处理反应过程中的溶胶所制备得到的TiO2纳米颗粒的光催化活性.结果表明:0.5%Sn4 、0.5%La3 、0.5%Y3 和0.5%Eu3 (质量分数)掺杂的TiO2纳米颗粒在降解甲基橙溶液的反应中,其光催化活性提高2%～7%;其它的掺杂则使TiO2纳米颗粒的光催化活性降低0.5%～25%;在TiO2纳米颗粒的制备过程中,对溶胶进行超声辐照可使其光催化活性提高15%以上,这是提高TiO2纳米颗粒光催化活性的一条新途径.

Sol-gel preparation and photocatalytic activities of TiO2 nanoparticles

The photocatalytic activities of TiO_2 nanoparticles doped with transition metal ions (Fe~3+ , Zn~2+ , Co~2+ , Ni~2+ , Cr~3+ and Sn~4+ ) and rare-earth metal ions (La~3+ , Pr~3+ , Nd~3+ , Ce~4+ , Sm~3+ , Eu~3+ , Gd~3+ , Y~3+ and Dy~3+ ) by sol-gel method and the TiO_2 nanoparticles obtained from the sol with ultrasonic irradiation during their sol-gel synthesis were investigated. The results show that the photocatalytic activities of TiO_2 nanoparticles doped with ~0.5% Sn~4+ , ~0.5% La~3+ , ~0.5% Y~3+ and ~0.5% Eu~3+ (mass fraction) increase 2%7%, while photocatalytic activities doped by others decreases 0.5%25% in the photocatalytic degradation of methylorange. The ultrasonic irradiation of the sol produced in the sol-gel synthesis of TiO_2 nanoparticles can enhance their photocatalytic activity above 15%, which is a novel way to improve the photocatalytic activities of TiO_2 nanoparticles.