ZIF-8/TiO_(2)复合介观晶体的制备及光催化活性  

ZIF-8/TiO_(2) Composite Mesocrystals:Preparation and Photocatalytic Activity

作　　者：马彬彬 钟婉菱 韩涧 陈椋煜 孙婧婧 雷彩霞 MA Binbin;ZHONG Wanling;HAN Jian;CHEN Liangyu;SUN Jingjing;LEI Caixia(School of Materials Science and Engineering,Xiamen University of Technology,Xiamen 361024,China;School of Resources,Environment and Materials,Guangxi University,Nanning 530004,China)

机构地区：[1]厦门理工学院材料科学与工程学院,福建省功能材料及应用重点实验室,厦门361024 [2]广西大学资源环境与材料学院,南宁530004

出　　处：《无机材料学报》2024年第8期937-944,共8页Journal of Inorganic Materials

基　　金：福建省自然科学基金项目(2022J011265);厦门理工学院科学技术研究项目(303021002)。

摘　　要：TiO_(2)的微观形貌、颗粒尺寸及比表面积是影响其光催化活性的重要因素,介观晶体是一类由无机纳米粒子沿着相同的结晶轴方向有序排列的超结构材料,在光催化领域具有重要的研究价值。本工作分别以六氟钛酸铵和硼酸为钛源和氟离子捕获剂,以无水乙醇和去离子水的混合溶液为溶剂,采用简单绿色的方法制备了NH4TiOF3介观晶体前驱体,然后用硼酸溶液酸洗,使NH4TiOF3介观晶体通过拓扑转变形成TiO_(2)介观晶体。最后采用沸石咪唑骨架材料ZIF-8纳米粒子对TiO_(2)介观晶体进行修饰,制备了ZIF-8/TiO_(2)复合介观晶体材料,并研究了其光催化降解亚甲基蓝的活性。实验结果表明,ZIF-8纳米粒子能够均匀生长在TiO_(2)介观晶体表面,形成比较致密的包覆层。ZIF-8/TiO_(2)复合介观晶体光催化剂具有较高的比表面积和较窄的禁带宽度,其光生电子和空穴的分离效率得到一定程度的提高。其中,样品M-TiZIF-2(加入4 mmol硝酸锌的复合介观晶体)展现出最高的光催化活性,其一级反应速率是TiO_(2)介观晶体的42倍,是ZIF-8单元材料的16倍。总之,在ZIF-8纳米粒子和TiO_(2)介观晶体的协同作用下,ZIF-8/TiO_(2)复合介观晶体材料显示出更优异的光催化性能。Microstructure,particle size and specific surface area of TiO_(2) are crucial factors influencing its photocatalytic activity.Mesocrystals represent a type of superstructural material formed by inorganic nanoparticles aligned along a common crystallographic axis,holding significant research potential in the field of photocatalysis.This study employed ammonium hexafluorotitanate and boric acid as titanium precursor and fluorine ion scavenger,respectively,and used a blend of anhydrous ethanol and deionized water as reaction medium.NH4TiOF3 mesocrystals precursors were prepared by a facile green method.Subsequently,washing with boric acid solution enabled the transformation of NH4TiOF3 mesocrystals into TiO_(2) mesocrysals through topotaxial conversion.Ultimately,the TiO_(2) mesocrystals were functionalized with ZIF-8 nanoparticles,and the photocatalytic degradation activity of the obtained ZIF-8/TiO_(2) composite mesocrystals was studied.The experimental results shows that ZIF-8 nanoparticles can uniformly nucleate on the surface of TiO_(2) mesocrystals,resulting in a relatively dense coating layer.ZIF-8/TiO_(2) composite photocatalyst exhibits a higher specific surface area and a narrower band gap.Meanwhile,the separation efficiency of photogenerated electrons and holes is also improved to a certain extent.Notably,the sample M-TiZIF-2(with addition of 4 mmol Zn(NO3)2)demonstrated superior photocatalytic activity,and achieved a first-order reaction rate of 42-fold that of TiO_(2) mesocrystals and 16-fold that of pristine ZIF-8 nanoparticles.In conclusion,the synergistic effect of ZIF-8 nanoparticles and TiO_(2) mesocrystals significantly augments the photocatalytic performance of the ZIF-8/TiO_(2) composite mesocrystal materials.

关 键 词：TiO_(2)介观晶体 ZIF-8纳米粒子 光催化 复合介观晶体 

分 类 号：TB332[一般工业技术—材料科学与工程]