羟基修饰MOFs的合成、表征和光催化机理

Synthesis,Characterization and Photocatalytic Mechanism of Hydroxyl Modified MOFs

合成了具有大的比表面积和结构容易修饰的金属有机框架材料(MOFs)光催化剂:MIL^-101(Cr)和MIL^-101(Cr)-2OH。利用红外、X射线粉末衍射、X射线光电子能谱等仪器对MIL^-101(Cr)和MIL^-101(Cr)-2OH光催化剂的结构进行表征分析。通过紫外-可见光漫反射光谱、ζ电位、电喷雾电离质谱系统地分析研究MOFs中不参与配位的给电子基团对光催化降解亚甲基蓝性能的影响。研究发现MIL^-101(Cr)-2OH中桥联配体2,5-二羟基对苯二甲酸上不参与配位的2个羟基,可以通过配体-金属的电荷转移作用影响光的吸收,从而调控光催化降解速率.

In this work,metal organic framework materials(MOFs)photocatalysts with large specific surface area and easy structure modification are synthesized:MIL^-101(Cr)and MIL^-101(Cr)-2OH.The structures of MIL^-101(Cr)and MIL^-101(Cr)-2OH photocatalysts were characterized by FT-IR,X-ray powder diffraction(PXRD),and X-ray photoelectron spectroscopy(XPS).The UV-visible diffuse reflectance spectroscopy(UV-Vis DRS),ζpotential,and electrospray ionization mass spectrometry(ESI-MS)were used to systematically analyze the effect of electron donat-ing groups in the MOFs on photocatalytic degradation of methylene blue(MB).It was found that the two hydroxyl groups that do not participate in MIL^-101(Cr)-2OH can affect the absorption of light through the action of ligand-metal charge transfer(LMCT),thereby regulating the photocatalytic degradation rate.