Improved hydrogen storage properties of MgH2 by Mxene (Ti3C2) supported MnO2

MgH2 is a promising high-capacity solid hydrogen storage material. In this work, MnO2-doped Ti3C2 (Ti3C2@MnO2) was synthesized and used as a catalyst to improve the hydrogen storage performance of MgH2. We found that the dehydrogenated 10 wt% Ti3C2@MnO2-doped MgH2 sample exhibited good hydrogen adsorption ability even at room temperature (30 & DEG;C), and could absorb 5.13 wt% of hydrogen in 400 s at 75 & DEG;C. The re-hydrogenated Ti3C2@MnO2-doped MgH2 sample started to release hydrogen at 182 & DEG;C and required 484 s to completely release hydrogen at 275 & DEG;C with a dehydrogenation capacity of 6.4 wt%. The Ti3C2@MnO2 composite did not change the thermodynamic properties of MgH2. In the MgH2 + Ti3C2@MnO2 sample, Ti3C2, TiO2, MnO2, MnO, and Mn combined with MgH2 to form Ti3C2/MgH2, TiO2/MgH2, MnO2/MgH2, MnO/MgH2, and Mn/MgH2 multiphase interfaces, which improved the hydrogen storage performance of MgH2. The findings of this work may provide a new strategy for preparing novel and efficient catalysts for hydrogen storage applications.

Automated summary

MnO2-doped Ti3C2 was used as a catalyst to enhance the hydrogen storage performance of MgH2. The doped sample exhibited good adsorption ability at room temperature and could absorb 5.13 wt% hydrogen in 400 s at 75°C. The composite did not alter the thermodynamic properties of MgH2 and formed multiphase interfaces, improving the hydrogen storage performance. This study provides a new strategy for preparing efficient catalysts for hydrogen storage applications.