基于“芳酸结构形貌调控的Zn-MOFs制备表征”构建无机化学综合实验

Construction of An Inorganic Comprehensive Experiment Based on“Preparation and Characterization of Zn-MOFs Regulated Morphology with Chemical Structures of Aromatic Acids”

金属有机框架化合物(MOFs)是有机配体与金属离子或金属簇通过配位键组装而成的具有分子内孔隙结构的有机-无机杂化材料,具有比表面积大、孔隙率高、孔径可调、稳定性好等特征,在催化、能源、药物输送及传感等领域广泛应用。MOFs的物性特征与其形貌及组成密切相关,故形貌调控至关重要。本文以对苯二甲酸、均苯三甲酸、2,6-萘二羧酸为有机配体,以锌离子为金属中心,采用室温沉淀法制备Zn-MOFs纳米材料体系,基于有机配体调控Zn-MOFs形貌。采用扫描电子显微镜表征其形貌,X-射线衍射光谱表征其晶体结构,红外光谱表征化学组成,紫外可见吸收光谱表征其光谱特性,并修饰至玻碳电极表面,构建光电化学界面,考察三种Zn-MOFs纳米材料的光电转换性能。通过该综合实验,有助于延伸无机化学金属配合物之理论基础,拓展光电化学及化学修饰电极知识领域,有利于强化科研创新意识、提升材料制备及表征相关实验技能、建立数据处理与结果分析的思维模式,有助于培养学生立志创新、勇于探索之精神。

Metal-organic frameworks(MOFs)are inorganic-organic hybrid materials with porous structure.MOFs are commonly prepared through the coordination reaction between metal ions(or metal clusters)and organic linkers.MOFs have been extensively applied in many research fields including catalysis,energy,drug delivery and sensing,due that they possess some advantages such as large specific surface area,high porosity,adjustable pore size and perfect stability.The physical characteristics of MOFs are closely relevant to their morphologies.Therefore,to regulate the morphology of MOFs is very important for the preparation of MOFs with specific functions.Herein,Zn-MOFs were facilely prepared by using zinc ion as metal center and terephthalic acid,trimesic acid and 2,6-naphthalene dicarboxylic acid as ligands with a room temperature precipitation method.The morphology of Zn-MOFs was regulated by varying the chemical structure of ligand.The obtained Zn-MOFs were characterized with scanning electron microscope for morphology,X-ray diffraction spectroscopy for crystal pattern,Fourier transform infrared spectroscopy for chemical structure and diffuse reflectance ultraviolet-visible spectroscopy for spectroscopic characteristics.Furthermore,Zn-MOFs were coated onto a glassy carbon electrode surface to construct photoelectrochemical platforms to investigate their photoelectric conversion properties.The designed comprehensive experiment can help students to extend the theoretical basis of metal complex in studying Inorganic Chemistry,expend their knowledge about electrochemistry and photoelectrochemistry,strengthen the consciousness of scientific research innovation,develop manipulative ability and experiment skill for the preparation and characterization of nanomaterials,create thinking model for data processing and the result analysis.In addition,the experience from this comprehensive experiment can encourage students to be ambitious enough to set goals in research innovation.