Six Ni-Mo catalysts with different metal contents were prepared and characterized by N2 adsorption and X-ray diffi＇actometry. The active phase microstructure of these catalysts was examined by the Raman spectroscopy,...Six Ni-Mo catalysts with different metal contents were prepared and characterized by N2 adsorption and X-ray diffi＇actometry. The active phase microstructure of these catalysts was examined by the Raman spectroscopy, temperature- programmed reduction （TPR）, X-ray photoelectron spectroscopy, and high-resolution transmission electron microscopy. Hydrodesulfurization （HDS） activity of catalyst samples were analyzed in a flow fixed-bed microreactor. The sulfidation degree of Mo and the length of the MoS2 slab slightly increased with the amount of metal loaded following sulfidation. This small change is attributed to polymolybdate species observed in all the oxidized catalysts. Weak metal-support interactions, as determined by the TPR technique, increased the NiSx sulfidation phase and MoS2 slab stacking. The HDS activity of the catalyst samples increased with the number of active sites. For high metal loading catalysts, their HDS activity was nearly identical because the sulfur atoms cannot easily approach active sites. This change is caused by the large number of stacked layers in the MoS2 slabs as well as the decrease in the specific surface area and pore volume of the catalyst samples with an increasing metal loading.展开更多
Metal-organic frameworks(MOFs),comprised of organic ligands and metal ions/metal clusters via coordinative bonds are highly porous,crystalline materials.Their tunable porosity,chemical composition,size and shape,and e...Metal-organic frameworks(MOFs),comprised of organic ligands and metal ions/metal clusters via coordinative bonds are highly porous,crystalline materials.Their tunable porosity,chemical composition,size and shape,and easy surface functionalization make this large family more and more popular for drug delivery.There is a growing interest over the last decades in the design of engineered MOFs with controlled sizes for a variety of biomedical applications.This article presents an overall review and perspectives of MOFs-based drug delivery systems(DDSs),starting with the MOFs classification adapted for DDSs based on the types of constituting metals and ligands.Then,the synthesis and characterization of MOFs for DDSs are developed,followed by the drug loading strategies,applications,biopharmaceutics and quality control.Importantly,a variety of representative applications of MOFs are detailed from a point of view of applications in pharmaceutics,diseases therapy and advanced DDSs.In particular,the biopharmaceutics and quality control of MOFs-based DDSs are summarized with critical issues to be addressed.Finally,challenges in MOFs development for DDSs are discussed,such as biostability,biosafety,biopharmaceutics and nomenclature.展开更多
基金SINOPEC for its financial support(No.108012/No.108041)
文摘Six Ni-Mo catalysts with different metal contents were prepared and characterized by N2 adsorption and X-ray diffi＇actometry. The active phase microstructure of these catalysts was examined by the Raman spectroscopy, temperature- programmed reduction （TPR）, X-ray photoelectron spectroscopy, and high-resolution transmission electron microscopy. Hydrodesulfurization （HDS） activity of catalyst samples were analyzed in a flow fixed-bed microreactor. The sulfidation degree of Mo and the length of the MoS2 slab slightly increased with the amount of metal loaded following sulfidation. This small change is attributed to polymolybdate species observed in all the oxidized catalysts. Weak metal-support interactions, as determined by the TPR technique, increased the NiSx sulfidation phase and MoS2 slab stacking. The HDS activity of the catalyst samples increased with the number of active sites. For high metal loading catalysts, their HDS activity was nearly identical because the sulfur atoms cannot easily approach active sites. This change is caused by the large number of stacked layers in the MoS2 slabs as well as the decrease in the specific surface area and pore volume of the catalyst samples with an increasing metal loading.
基金financially supported by the National Key R&D Program of China(No.2020YFE0201700)National Nature Science Foundation of China(No.81773645)a public grant overseen by the French National Research Agency(ANR),France as part of the“Investissements d’Avenir”program(Labex NanoSaclay:ANR-10-LABX-0035,France)
文摘Metal-organic frameworks(MOFs),comprised of organic ligands and metal ions/metal clusters via coordinative bonds are highly porous,crystalline materials.Their tunable porosity,chemical composition,size and shape,and easy surface functionalization make this large family more and more popular for drug delivery.There is a growing interest over the last decades in the design of engineered MOFs with controlled sizes for a variety of biomedical applications.This article presents an overall review and perspectives of MOFs-based drug delivery systems(DDSs),starting with the MOFs classification adapted for DDSs based on the types of constituting metals and ligands.Then,the synthesis and characterization of MOFs for DDSs are developed,followed by the drug loading strategies,applications,biopharmaceutics and quality control.Importantly,a variety of representative applications of MOFs are detailed from a point of view of applications in pharmaceutics,diseases therapy and advanced DDSs.In particular,the biopharmaceutics and quality control of MOFs-based DDSs are summarized with critical issues to be addressed.Finally,challenges in MOFs development for DDSs are discussed,such as biostability,biosafety,biopharmaceutics and nomenclature.
