摘要
Two kinds of metal-organic frameworks(MOFs) based on Co(Ⅱ) and Fe(Ⅱ) as metal ions and trimasic acid(TMA) as organic linker were synthesized. They were used to prepare corresponding Mg H2-TM MOF(TM = Co, Fe) composites via ball-milling. X-ray diffraction analyses show the formation of Mg2 Co and α-Fe phases in Mg H2-TMMOF composites after decomposition. Both of the well dispersed Mg2Co andα-Fe nanoparticles exhibit considerable catalytic efficiency in accelerating the sorption kinetics of Mg H2.The dehydrogenated MgH2-Fe MOF composite shows faster hydriding kinetics than the pure Mg H2 and Mg H2-CoMOF. Meanwhile, the apparent dehydrogenation activation energy(Ed) of the Mg H2-Co MOF and Mg H2-Fe MOF composites are 151.3 ± 9.4 and 142.3 ± 6.5 kJ/mol H2, both of which are lower than that of pure Mg H2(181.4 ± 9.2 kJ/mol H2). The improvement on the sorption kinetics of the Mg H2-TM MOF powders is mainly attributed to the catalytic effects of nano-sized Mg2 Co and α-Fe formed on the surface of Mg/Mg H2 particles.
Two kinds of metal-organic frameworks(MOFs) based on Co(Ⅱ) and Fe(Ⅱ) as metal ions and trimasic acid(TMA) as organic linker were synthesized. They were used to prepare corresponding Mg H2-TM MOF(TM = Co, Fe) composites via ball-milling. X-ray diffraction analyses show the formation of Mg2 Co and α-Fe phases in Mg H2-TMMOF composites after decomposition. Both of the well dispersed Mg2Co andα-Fe nanoparticles exhibit considerable catalytic efficiency in accelerating the sorption kinetics of Mg H2.The dehydrogenated MgH2-Fe MOF composite shows faster hydriding kinetics than the pure Mg H2 and Mg H2-CoMOF. Meanwhile, the apparent dehydrogenation activation energy(Ed) of the Mg H2-Co MOF and Mg H2-Fe MOF composites are 151.3 ± 9.4 and 142.3 ± 6.5 kJ/mol H2, both of which are lower than that of pure Mg H2(181.4 ± 9.2 kJ/mol H2). The improvement on the sorption kinetics of the Mg H2-TM MOF powders is mainly attributed to the catalytic effects of nano-sized Mg2 Co and α-Fe formed on the surface of Mg/Mg H2 particles.
基金
supported financially by the National Natural Science Foundation of China (No. 51771112)
the National Key Research & Development Project (No. 2018YFB1502104)
the Shanghai Science and Technology Commission (No. 14JC1491600)
the Shanghai Education Commission “Shuguang” Scholar Project (No. 16SG08)