埃洛石纳米管原位构筑Z型Bi2MoO6/Au/Cu2O光催化剂的异质界面机制及协同催化

Water organic pollution is always a major world-wide problem and photocatalytic technology is regarded as an important green way to solve this problem. While the existing photocatalytic material has some disadvantages such as high carrier recombination rate, poor stability and weak adsorption. Based on natural halloysite nanotube structure and high adsorption properties, this project draws to use the graft modifier to modify halloysite wall in order to improve its induced orientation and solve the above problems. Visible light activity Bi2MoO6 and Cu2O used as light system Ⅰ and Ⅱ, Au used as efficient electron transfer body, shell(Bi2MoO6)-core(Au)-shell (Cu2O) Z-scheme catalytic system is synthesized through layer by layer assembly. It tends to focus on the transformation and directional induced law of the graft modifier on the wall and the catalyst unit respectively, definite carriers transfer mechanism in Z-scheme heterojunction interface and synergy mechanism between the adsorption of halloysite and the catalysis of catalyst. Combined with the structure change of Z-scheme catalytic system, it reveals relationship mechanism among the structure of the hetero interface and carrier mobility, migration channel, achieves controllable preparation of the catalyst structure, optimizes the adsorption and catalytic cooperative behavior. Nano-mineral based Z-scheme photocatalyst which is expected to be applied in degradation of water organic contaminants efficiently and greenly will be prepared. It will provide theoretical and experimental basis for application of this type of material.

水体有机污染历来是困扰世界各国的难题，光催化技术被视为解决该难题的重要绿色途径，而现有光催化材料存在载流子复合率高、稳定性差和吸附性弱的缺陷。为解决上述不足，本项目基于天然埃洛石独特的纳米管结构和良好的吸附性能，采用接枝改性剂对埃洛石管壁进行修饰，改善其表面基团的定向诱导作用，选择具有可见光活性的Bi2MoO6和Cu2O作光系统Ⅰ、Ⅱ，Au作高效电子转移体，在埃洛石表面通过层层组装原位构筑壳(Bi2MoO6)-核(Au)-壳(Cu2O)结构的高效Z型催化体系。拟着重研究改性剂对埃洛石管壁的接枝改造作用及对催化剂单元的定向诱导规律，阐明载流子在Z型异质界面中的迁移机制和吸附与催化协同作用机理，明确异质界面结构与载流子迁移率、迁移通道之间的关系。通过调控催化剂的微观结构，优化吸附和催化的协同作用，制备出高效、绿色降解水体有机污染物的纳米矿物基Z型光催化剂，为此类材料的开发提供理论和实验依据。

埃洛石纳米管（HNTs）是一种纳米管状结构的天然硅酸盐矿物，因其比表面积大与表面基团丰富，使其成为具有较强吸附性能的光催剂载体材料。本项目围绕以埃洛石代表的多孔矿物展开复合光催化材料的制备、结构调控、性能测试和机理分析等研究。采用预先提纯、活性剂表面改性、水热法、溶胶凝胶法和直接沉淀法等工艺，通过组分优化、温度控制和结构调控等方式，开展了Bi2MoO6/埃洛石、Au-Bi2MoO6/埃洛石、BiVO4/埃洛石、ZnFe2O4/埃洛石、Cu2O-Au-Bi2MoO6、Cu2O/Bi2MoO6@埃洛石、Au-Bi2MoO6/硅藻土、g-C3N4/BiVO4@埃洛石和N-TiO2/g-C3N4@硅藻土为代表的一系列矿物基二元/三元异质复合光催化剂的结构设计、性能表征和应用基础研究；分析了矿物表面基团、结构特性以及催化剂载体间的耦合作用过程，明确了矿物基二元/三元异质复合光催化剂的构效机制及其光催化、回收和重复利用性能。在本项目的资助下，共发表（录用）论文8篇，其中ESI高被引论文1篇、SCI收录4篇、EI收录2篇；申请发明专利12项，其中授权6项；参加国际国内学术会议4次；获建材科技进步一等奖1项（排名第8）；培养硕士研究生2名、本科生3名，指导学生获得大学生科技创新活动立项2项，获得校级课外学术科技作品竞赛一等奖1项。