Improved hydrogen storage in the modified metal-organic frameworks by hydrogen spillover effect

摘要

In the present work, in order to enhance hydrogen storage capacity of metal-organic frameworks (MOFs) at room temperature, two ways are carried out for MOFs modification. One is a simple doping of metal-supported carbon catalyst with MOFs; the other is doping metal-supported carbon catalyst through a carbon bridge with MOFs. Pressure-composition (P-C) isotherms of these modified and unmodified samples are investigated using Severts-type apparatus at 293 K and the pressure ranging from 0.01 to 5.0 MPa. Through these modification techniques based on the hydrogen spillover effect, especially the carbon-bridged catalyst doping technique, the modified samples witnessed a great increase in hydrogen uptakes when compared with the pristine samples. The storage capacity of modified MIL-101 and MIL-53 at 5.0 MPa and 293 K are found to be 1.14 and 0.63 wt%, which are greatly increased as compared to the pristine-MOFs.