MOFs derived Ni-Mn bimetal nano-catalysts with enhanced hydrogen pump effect for boosting hydrogen sorption performance of MgH2

作者：Tianping Huang, Yingyan Zhao, Bolun Wang, Yinghui Li, Jiaqi Zhang, Xusheng Wang, Yanyue Wang, Hao Du, Manquan Fang, Jianxin Zou · 发表于：Journal of Magnesium and Alloys · 年份：2024 · DOI：10.1016/j.jma.2024.11.008 · 被引用次数：20 · 研究领域：Hydrogen Storage and Materials、Hybrid Renewable Energy Systems、Ammonia Synthesis and Nitrogen Reduction

• Highly effective NiMn-MOF derivatives were synthesized using a one-pot method. • Peak dehydrogenated temperature of MgH 2 -NiMn-MOF derivative is 218.2 °C (3 °C/min). • The composite presents remarkable rehydrogenated ability at near room temperature. • The enhancing “hydrogen pumping” mechanism of Mg 6 MnO 8 and Mg 2 NiH 4 /Mg 2 Ni is revealed. In the present work, highly effective Ni-MnO binary nanocomposite catalysts were designed and synthesized using a one-pot method from Ni-Mn based bi-metal organic frameworks (MOFs). These nanocomposites were introduced into MgH 2 through ball milling as catalysts to enhance the hydrogen storage properties of MgH 2 . Through varying the Ni/Mn ratio in the bimetal MOFs, it is found that the Ni 1 Mn 1− MOF derived catalyst showed the best promotion effect on MgH 2 . The MgH 2 –10 wt.% Ni 1 Mn 1− MOF derivative demonstrated favorable overall performance with the low desorption peak temperature (218.2 °C) with a saturated hydrogen capacity of 6.42 wt.% and rapid hydrogen release/uptake kinetics. It can still reabsorb about 1.15 wt.% H 2 within 30 min at a temperature as low as 50 °C. Both performance tests (DSC and TPD) and structural characterizations (XRD, HRTEM, etc.) revealed that the synergistic role of in situ formed Mg 6 MnO 8 and Mg 2 NiH 4 /Mg 2 Ni phases for improving the hydrogen sorption properties of MgH 2 . Theoretical calculations reveal that Mg 6 MnO 8 destabilizes metal-H bonds in MgH 2 and Mg 2 NiH 4 , leading to an enh...