Hydrogen storage mechanism of metal–organic framework materials based on metal centers and organic ligands

Abstract

The effective storage and utilization of hydrogen energy is expected to solve the problems of energy shortage and environmental pollution currently faced by human society. Metal–organic framework materials (MOFs) have been shown by scientists to be very potential hydrogen storage materials. However, the current design methods and strategies for MOFs are still generally in the trial-and-error stage, and the research works are at the overall level. To solve the problems of directional design and rational construction of new MOFs, this work uses the principles and methods of coordination chemistry and crystal engineering to carry out the theoretical design and mechanism research of new MOFs for high-efficiency hydrogen storage application scenarios. In this study, the structures selected for theoretical calculation were divided into two types: different ligands for the same metal (IRMOFs, MOF-205, and DUT-23-Zn) and different metals for the same ligand (DUT-23-M [(M = Co, Ni, Cu, and Zn]). The model construction process, hydrogen loading with temperature, specific surface area, hydrogen adsorption energy, charge density and hydrogen storage mechanism of the above structures were analyzed, and the key indicators that may affect the hydrogen storage performance of MOFs were summarized: type and quantity of coordination metals, temperature, pressure, adsorption site and specific surface area.