金属-有机框架在光催化中的应用  

Applications of metal-organic frameworks in photocatalysis

作　　者：梁祥 陈莲芬 张利[1] 苏成勇[1] 

机构地区：[1]中山大学化学学院,广州510275

出　　处：《科学通报》2018年第3期248-265,共18页Chinese Science Bulletin

基　　金：中山大学实验室开放基金(201610250060);广州市计划科技项目(201707010168);国家自然科学基金(21373278;91222201)资助

摘　　要：为了缓解并最终解决能源问题,自20世纪至今,人们一直在探索如何利用光能如太阳光高效环保地将水分解生成清洁能源氢气,以及利用光能实现人工二氧化碳的还原过程(模拟光合作用).金属-有机框架(metalorganic frameworks,MOFs)具有独特的物理和化学性质,如超高的比表面积、可设计和精确控制的孔洞、对光生电子的多种传递机制、方便与染料分子连接、或是可直接引入具有优异光学活性的配体和金属.作为一大类近二十年来迅速发展的微孔/介孔材料,在光催化领域引起了越来越多研究者的兴趣.本文通过一些代表性的实例总结了MOFs作为新兴光催化材料的独特优势和内在优点,展望了MOFs在光催化应用中的机遇和发展前景.首先介绍了MOFs的基本概念和特性,阐述了相对于其他材料而言,MOFs的独特优势,并解释了为何它能在光催化领域引起广泛的关注;之后将用于光催化的MOFs分成3大类,分别是:(1)依靠无机金属簇作为半导体结点的MOFs;(2)引入具有光活性的有机连接体(即配体)的MOFs;(3)以及利用超分子化学中主-客体相互作用,在孔洞中包覆氧化还原物种的MOFs,其中又细分为包覆纳米粒子或者金属催化剂、多金属含氧酸盐和其他纳米复合材料3个小类;最后,总结了MOFs在光催化中应用时仍需解决的问题,展望了该领域的研究方向.To relieve and solve the energy problem, effective methods to use solar energy must be built up. To be more specifically, we need figure out how to utilize sunlight for water splitting reaction, giving rise to hydrogen as clean energy, and photoreduction of carbon dioxide, leading to the formation of useful liquid products（e.g., HCOO^-, HCHO and CH_3OH） or gaseous products（e.g., CH_4 and CO）. As a class of distinguished and unique materials, metal-organic frameworks（MOFs） have drawn a lot of attention, considering that they display special physical and chemical properties such as exceedingly high surface areas, designable and controllable cavities, different mechanisms of photo-induced electrons transfer, and moreover photoactive parts can be easily introduced into MOFs by either encapsulating dye molecules into the cavities or constructing the frameworks with optically active bridging ligands or metal nodes. In this review, we have commented on the challenges in this field, summarized the unique advantages and inherent merits of MOFs as the emerging materials, and pointed out the opportunities and development strategies of MOFs for their applications in photocatalysis. Firstly, we have introduced MOFs＇ concepts and features, distinguishing them from other porous materials, and their advantages in photocatalysis. MOFs are crystalline porous materials formed from ligands（including metalloligands） and transition-metal nodes. The structures of MOFs are of facile design, and can be further modified through post-synthetic methods. Some MOFs display high thermal and chemical stability, which can be stable up to 500℃ and resist a variety of reaction media either organic solvents or aqueous, even in acidic and basic solutions. MOFs can be photoresponsive through light absorption by the organic linker, the metal oxide nodes or the photoactive species entrapped in the voids. Photoexcitation of the light absorbing units in MOFs generates the excited state, which might induce photocatalytic activity. Next

关 键 词：金属-有机框架 异相催化 光催化 水分解 CO2还原 

分 类 号：O643.36[理学—物理化学]