Zeolitic imidazole frameworks(ZIFs)are a class of three-dimensional(3D)skeletalmaterials with zeolitic topology composed of metal ions and imidazolium ligands,which combine the advantages of zeolites and metal-organic...Zeolitic imidazole frameworks(ZIFs)are a class of three-dimensional(3D)skeletalmaterials with zeolitic topology composed of metal ions and imidazolium ligands,which combine the advantages of zeolites and metal-organic frameworks.ZIFs are widely used for adsorption of carbon dioxide(CO_(2))from flue gas due to its excellent hydrophobicity,chemical stability,thermal stability and gas adsorption properties.This study focuses on the effects of structures of ZIFs on CO_(2)capture and separation from the viewpoints of topologies,pore channels,ligand functional groups and composite structures.On this basis,the mechanisms of CO_(2)adsorption and selective separation are reviewed,as well as the challenges such as hydrophobicity,thermal and chemical stability faced by ZIFs in practical applications.展开更多
针对印染废水难以处理而对环境造成污染问题,以活性黑染料为目标污染物,制备了一种ZIF-8/MCM-48新型复合吸附材料,并采用X射线衍射(X-ray Diffraction,XRD)、扫描电镜(Scanning Electron Microscopy,SEM)、N_(2)的吸脱附曲线对其形貌、...针对印染废水难以处理而对环境造成污染问题,以活性黑染料为目标污染物,制备了一种ZIF-8/MCM-48新型复合吸附材料,并采用X射线衍射(X-ray Diffraction,XRD)、扫描电镜(Scanning Electron Microscopy,SEM)、N_(2)的吸脱附曲线对其形貌、结构、组成进行表征,研究了其对活性黑染料废水的吸附性能,并通过调整ZIF-8/MCM-48复合物比例、活性黑染料废水浓度、染料废水pH值及吸附时间,来确定最大吸附量和最佳吸附条件。结果表明,ZIF-8/MCM-48复合吸附剂的投加量为0.4 g/L、废水pH值为6、吸附时间为50 min时,0.15 g/L活性黑染料废水的脱色率达到了最高,为58.7%。最后对吸附过程进行了动力学分析,发现其符合二级动力学方程。展开更多
AgVO_(3)/ZIF-8 composites with enhanced photocatalytic effect were prepared by the combination of AgVO_(3)and ZIF-8.X-ray diffraction(XRD),scanning electron microscopy(SEM),high-power transmission electron microscopy(...AgVO_(3)/ZIF-8 composites with enhanced photocatalytic effect were prepared by the combination of AgVO_(3)and ZIF-8.X-ray diffraction(XRD),scanning electron microscopy(SEM),high-power transmission electron microscopy(HRTEM),X-ray photoelectron spectroscopy(XPS),ultraviolet-visible diffuse reflectance spectroscopy(UV-Vis DRS),photoluminescence(PL)spectroscopy,electron spin resonance(ESR)spectroscopy,transient photocurrent and electrochemical impedance spectroscopy(EIS)were used to characterize binary composites.Tetracycline(TC)was used as a substrate to study the performance efficiency of the degradation of photocatalysts under light conditions,and the degradation effect of TC was also evaluated under different mass concentrations and ionic contents.In addition,we further investigated the photocatalytic mechanism of the binary composite material AgVO_(3)/ZIF-8 and identified the key active components responsible for the catalytic degradation of this new photocatalyst.The experimental results show that the degradation efficiency of 10%-AZ,prepared with a molar ratio of 10%AgVO_(3)and ZIF-8 to TC,was 75.0%.This indicates that the photocatalytic activity can be maintained even under a certain ionic content,making it a suitable photocatalyst for optimal use.In addition,the photocatalytic mechanism of binary composites was further studied by the active species trapping experiment.展开更多
基金supported by the Fundamental Research Program of Shanxi Province(Nos.20210302124003 and 20210302124015)the Scientific and Technological Innovation Programs of Higher Education Institutions in Shanxi(No.2021L032)+2 种基金the National Natural Science Foundation of China(No.52103307)China Postdoctoral Science Foundation(No.2023M742575)the General Program of Shanxi Province(No.202203021211150).
文摘Zeolitic imidazole frameworks(ZIFs)are a class of three-dimensional(3D)skeletalmaterials with zeolitic topology composed of metal ions and imidazolium ligands,which combine the advantages of zeolites and metal-organic frameworks.ZIFs are widely used for adsorption of carbon dioxide(CO_(2))from flue gas due to its excellent hydrophobicity,chemical stability,thermal stability and gas adsorption properties.This study focuses on the effects of structures of ZIFs on CO_(2)capture and separation from the viewpoints of topologies,pore channels,ligand functional groups and composite structures.On this basis,the mechanisms of CO_(2)adsorption and selective separation are reviewed,as well as the challenges such as hydrophobicity,thermal and chemical stability faced by ZIFs in practical applications.
文摘AgVO_(3)/ZIF-8 composites with enhanced photocatalytic effect were prepared by the combination of AgVO_(3)and ZIF-8.X-ray diffraction(XRD),scanning electron microscopy(SEM),high-power transmission electron microscopy(HRTEM),X-ray photoelectron spectroscopy(XPS),ultraviolet-visible diffuse reflectance spectroscopy(UV-Vis DRS),photoluminescence(PL)spectroscopy,electron spin resonance(ESR)spectroscopy,transient photocurrent and electrochemical impedance spectroscopy(EIS)were used to characterize binary composites.Tetracycline(TC)was used as a substrate to study the performance efficiency of the degradation of photocatalysts under light conditions,and the degradation effect of TC was also evaluated under different mass concentrations and ionic contents.In addition,we further investigated the photocatalytic mechanism of the binary composite material AgVO_(3)/ZIF-8 and identified the key active components responsible for the catalytic degradation of this new photocatalyst.The experimental results show that the degradation efficiency of 10%-AZ,prepared with a molar ratio of 10%AgVO_(3)and ZIF-8 to TC,was 75.0%.This indicates that the photocatalytic activity can be maintained even under a certain ionic content,making it a suitable photocatalyst for optimal use.In addition,the photocatalytic mechanism of binary composites was further studied by the active species trapping experiment.
