CAJ | 학술논문

通过分步沉积法制备了不同Zr/Ti摩尔比的锶锆钛(SZT)复合氧化物催化剂,以X射线衍射(XRD)、扫描电镜(SEM)、透射电镜(TEM)、紫外-可见(UV-Vis)漫反射光谱等表征手段考察不同Zr/Ti摩尔比下SZT催化剂的结构形态,以可见光下光催化降解亚甲基蓝为模型反应考察样品的光催化活性.结果表明: Zr/Ti 摩尔比<1时SZT 催化剂发生 Zr4+与 Ti4+同质替换,引起晶格缺陷,光催化活性小幅提高; Zr/Ti摩尔比≥1时SZT 催化剂产生SrZrO3/TinO2n-1(n=4,9)的新晶相, TinO2n-1(n=4,9)的存在有利于光生电子-空穴的传导与分离,可大幅提高催化剂光催化活性.其中, SZT-5/5表现出最高的光催化活性,其一级反应速率常数达到0.2133 min-1,是同等光照条件下纯SrTiO3样品(0.0158 min-1)的13.5倍.
통과분보침적법제비료불동Zr/Ti마이비적송고태(SZT)복합양화물최화제,이X사선연사(XRD)、소묘전경(SEM)、투사전경(TEM)、자외-가견(UV-Vis)만반사광보등표정수단고찰불동Zr/Ti마이비하SZT최화제적결구형태,이가견광하광최화강해아갑기람위모형반응고찰양품적광최화활성.결과표명: Zr/Ti 마이비<1시SZT 최화제발생 Zr4+여 Ti4+동질체환,인기정격결함,광최화활성소폭제고; Zr/Ti마이비≥1시SZT 최화제산생SrZrO3/TinO2n-1(n=4,9)적신정상, TinO2n-1(n=4,9)적존재유리우광생전자-공혈적전도여분리,가대폭제고최화제광최화활성.기중, SZT-5/5표현출최고적광최화활성,기일급반응속솔상수체도0.2133 min-1,시동등광조조건하순SrTiO3양품(0.0158 min-1)적13.5배.
@@@@A series of Sr-Zr-Ti (SZT) mixed oxide catalysts were prepared by a fractional-precipitation method. These photocatalysts were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), and ultraviolet visible (UV-Vis) diffuse reflectance absorption spectra. Photocatalytic degradation of methylene blue was investigated to determine the photoactivity of the catalyst. It was shown that with a Zr/Ti ratio<1, the SZT mixed oxide catalysts showed improved photocatalytic activity. This was attributed to lattice defects creating active photocatalytic sites because of Zr4+ doping. For Zr/Ti ratios≥1, the catalysts showed markedly improved photocatalytic activity because of new crystal ine phases of SrZrO3 and TinO2n-1 (n=4, 9) that facilitated splitting and conduction for electron/hole. Typical SZT samples (Zr/Ti=4) showed the highest photocatalytic activity, with first-order reaction rate constant 13.5 times that of a SrTiO3 sample.