Nickel, Graphene, and Yttria-Stabilized Zirconia (YSZ)-Added Mg by Grinding in Hydrogen Atmosphere for Hydrogen Storage

Myoung Youp Song,Eunho Choi,Young Jun Kwak

doi:10.3390/met9121347

Abstract

Magnesium (Mg) has good hydrogen storage features except for its slow reaction kinetics with hydrogen and high hydride decomposition temperature. Yttria (Y2O3)-stabilized zirconia (ZrO2) (YSZ), nickel (Ni), and graphene were picked as additives to Mg to solve these problems. Samples with a composition of 92.5 wt% Mg + 2.5 wt% YSZ + 2.5 wt% Ni + 2.5 wt% graphene (designated as Mg + YSZ + Ni + graphene) were prepared by grinding in hydrogen atmosphere. The activation of Mg + YSZ + Ni + graphene was finished at the third cycle (n = 3). Mg + YSZ + Ni + graphene had an efficient hydrogen storage capacity (the amount of hydrogen absorbed for 60 min) over 7 wt% (7.11 wt%) at n = 1. Mg + YSZ + Ni + graphene contained Mg2Ni phase after cycling. The addition of Ni and Ni + YSZ greatly increased the initial hydride formation and decomposition rates, and the amount of hydrogen absorbed and released for 60 min, Ha (60 min) and Hd (60 min), respectively, of a 95 wt% Mg + 5 wt% graphene sample (Mg + graphene). Rapid nucleation of the Mg2Ni-H solid solution in Ni-containing samples is believed to have led to higher initial decomposition rates than Mg + graphene and Mg. The addition of YSZ also enhanced the initial decomposition rate and Hd (60 min) compared to a sample with a composition of 95 wt% Mg + 2.5 wt% Ni + 2.5 wt% graphene (Mg + Ni + graphene).

Highlights

Magnesium (Mg) has good hydrogen storage features except its slow reaction kinetics with hydrogen and high hydride decomposition temperature [1,2,3,4]
The shape of the particles was spherical and the observed by scanning electron microscopy (SEM) at two different magnifications
The particles appeared to consist of fine particles

Summary

Introduction

Magnesium (Mg) has good hydrogen storage features except its slow reaction kinetics with hydrogen and high hydride decomposition temperature [1,2,3,4]. Attempts to solve these problems were made by adding transition metals [5,6,7] and by preparing Mg-including compounds [8]. Oxides can be crushed during grinding in mills because they are brittle. The hydride formation and decomposition kinetics of Mg have been ameliorated by adding oxides to MgH2 or. Yttria (Y2 O3 )-stabilized zirconia (ZrO2 ) (YSZ) is used for tooth crowns due to its hardness and chemical inertness [19]. We were interested in YSZ as an oxide additive

Methods

Results

Conclusion