Hydrogen storage properties of MgH2 + 20 wt.% Na2WO4 composite. (December 2015)

• Record Type: Journal Article
• Authors: Zhang, Wei; Shen, Na; Han, Shumin; Chen, Yang; Xu, Guang; Ke, Dandan
• Is Part Of: Materials research bulletin. Volume 72(2016)
• Page Start: 197
• Page End: 203
• Publication Date: 2015-12
• Subjects: A. Composites -- A. Hydrides -- D. Catalytic properties; Materials -- Periodicals; Crystal growth -- Periodicals; Matériaux -- Périodiques; Cristaux -- Croissance -- Périodiques; Crystal growth; Materials; Periodicals; 620.11
• DOI: 10.1016/j.materresbull.2015.07.042
• Languages: English
• ISSNs: 0025-5408

Abstract

Graphical abstract: Highlights: The influence of Na2 WO4 effect on MgH2 hydrogen storage properties is studied. Activation energy of MgH2 desorption is remarkably reduced with the dopant of Na2 WO4 . The improvement can be attributed to MgWO4 formation during ball milling. Abstract: The hydrogen storage properties of MgH2 ball milled with 20 wt.% Na2 WO4 have been investigated. The MgH2 + 20 wt.% Na2 WO4 composite has favorable hydrogenation and dehydrogenation properties as well as low decomposition temperature. When compared with the pristine MgH2, the total hydrogen absorption capacity of MgH2 + 20 wt.% Na2 WO4 composite increased from 0.98 wt.% to 2.27 wt.% in 20 min at 423 K, and the maximum hydrogen desorption capacity of MgH2 + 20 wt.% Na2 WO4 composite increased by 1.3 wt.% at 573 K. DTA and the Kissinger desorption kinetics analysis results indicated that the dehydrogenation activation energy of MgH2 + 20 wt.% Na2 WO4 composite is 83.10 kJ/mol, 39 kJ/mol lower than that of the pristine MgH2 . The XRD pattern provided that the in-situ formed MgWO4, acting as the catalyst during ball milling, improved the hydrogen storage properties of MgH2 .