Gao Haiguang, Song Mengcheng, Zhao Baozhou, Liu Jiangchuan, Shi Rui, Liu Yana, Hu Xiaohui, Zhu Yunfeng
Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology, School of Petrochemical Engineering, Changzhou University, Changzhou 213164, PR China.
Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology, School of Petrochemical Engineering, Changzhou University, Changzhou 213164, PR China.
J Colloid Interface Sci. 2025 Jan 15;678(Pt B):343-352. doi: 10.1016/j.jcis.2024.09.056. Epub 2024 Sep 6.
Magnesium hydride (MgH) as an ideal hydrogen storage carrier whose hydrogen storage performance can be effectively improved by transition metal-based catalysts. To construct highly active catalysts, much attention has been paid to the regulation of transition metal components while less attention has been paid to non-transition metal components especially oxygen, leading certain limitations. Herein, further improved hydrogen storage performance of MgH can be obtained by adjusting oxygen vacancy content in molybdenum trioxide (MoO) catalyst. Specifically, compared with pure MgH (1.1 wt%) and MgH-10 wt% MoO (4.5 wt%), more hydrogen (5.9 wt%) can be released by MgH-10 wt% MoO (MoO with abundant oxygen vacancies) at 300.0 °C within 499.0 s. Besides, superb capacity retention (6.1 wt%, 99.0 %) after 50 isothermal hydrogen ab/desorption cycles can be obtained for MgH-10 wt% MoO. Through rigorous comparative experiments and theoretical calculations, the excellent catalytic activity of MoO is demonstrated to come from the abundant oxygen vacancies and the active substances (polyvalent Mo and nano-sized MgO) it assists to form during ball milling process. This work verifies the feasibility for further improving the catalytic activity of transition metal-based catalysts by tuning non-transition metal elements and thus provides a new strategy in catalyzed MgH system.
氢化镁（MgH）作为一种理想的储氢载体，其储氢性能可通过过渡金属基催化剂得到有效改善。为构建高活性催化剂，人们对过渡金属组分的调控给予了大量关注，而对非过渡金属组分尤其是氧的关注较少，这导致了一定的局限性。在此，通过调节三氧化钼（MoO）催化剂中的氧空位含量，可以进一步提高MgH的储氢性能。具体而言，与纯MgH（1.1 wt%）和MgH-10 wt% MoO（4.5 wt%）相比，MgH-10 wt% MoO（具有大量氧空位的MoO）在300.0 °C下499.0 s内可释放更多氢气（5.9 wt%）。此外，MgH-10 wt% MoO在50次等温吸/放氢循环后可获得出色的容量保持率（6.1 wt%，99.0%）。通过严格的对比实验和理论计算，证明MoO的优异催化活性源于其丰富的氧空位以及在球磨过程中协助形成的活性物质（多价Mo和纳米级MgO）。这项工作验证了通过调节非过渡金属元素进一步提高过渡金属基催化剂催化活性的可行性，从而为催化MgH体系提供了一种新策略。
