TiO_2/多孔g-C_3N_4纳米复合材料制备及性能研究  

Synthesis of Porous TiO_2/g-C_3N_4 Nanocomposites with Enhanced Visible-Light Photocatalytic Properties

作　　者：杨辉[1,2] 沈建超[1] 冯宇[1] 蔡奇风 吴春春 马青松[3] 申乾宏[1,2] 

机构地区：[1]浙江大学材料科学与工程学院,浙江杭州310027 [2]浙江大学浙江加州国际纳米技术研究院,浙江杭州310058 [3]国防科技大学新型陶瓷纤维及其复合材料重点实验室,湖南长沙410073

出　　处：《稀有金属材料与工程》2016年第S1期467-471,共5页Rare Metal Materials and Engineering

基　　金：国家科技支撑计划项目(2013BAJ10B05)

摘　　要：以硫酸钛为钛源,采用水热法成功制备了TiO_2纳米颗粒均匀负载于多孔g-C3N4表面的复合光催化材料。利用X射线衍射(XRD)、红外光谱(FT-IR)、扫描电子显微镜(SEM)、透射电子显微镜(TEM),紫外-可见漫反射(DRS)和荧光光谱(PL)等手段对样品进行表征,并以甲基橙为目标分解物考察了样品的可见光催化活性。结果表明:质子化作用是形成多孔结构的主要原因,且多孔性与Ti(SO4)2浓度高度相关。多孔结构的产生显著提高了复合材料对甲基橙的吸附能力。另一方面,TiO_2在g-C3N4表面原位形核生长,形成纳米结,光生电子-空穴对可通过纳米结有效分离,从而提高复合材料量子效率,增强光催化活性。不过,负载TiO_2后,复合材料的可见光响应特性有所降低。综合来看,当TiO_2与g-C3N4摩尔比为1/3时,所得复合材料光催化活性最强,降解甲基橙的一级反应速率常数为单一g-C3N4的11.1倍。A network structured porous g-C_3N_4 with TiO_2 nanoparticles uniformly loaded on the surface was fabricated by a simple hydrothermal method. X-ray diffractometer(XRD), scanning electron microscopy(SEM), transmission electron microscopy(TEM), UV-vis spectroscopy and photoluminescence spectroscopy(PL) were adopted to analyze the structure-property relationship of samples. The results show that the formation of network pore structure in g-C_3N_4 matrix is mainly induced by the protonation of base functionalities(-C-N-), which is highly dependent on the concentration of Ti(SO_4)_2 aqueous solution. The uniformly and close interface between these two components is favorable for the highly efficient interparticle electron transfer, therefore achieving enhanced photocatalytic properties. However, the loading of Ti O_2 nanoparticles on the surface of g-C_3N_4 leads to the decrease of the visible-light response ability. Therefore, under the joint action of these factors, the porous Ti O_2/g-C3N4 nanocomposites achieve the best photocatalytic activity when the mole ratio of Ti O_2:g-C3N4 reaches 1:3, and the visible-light photocatalytic activity of Ti O_2/g-C3N4 nanocomposite is about as 11.1 times high as that of pure g-C3N4 without modification.

关 键 词：多孔g-C3N4 TiO2/g-C3N4纳米结 水热法 可见光催化 

分 类 号：TB33[一般工业技术—材料科学与工程]