Superior Hydrogen Sorption Kinetics of Ti0.20Zr0.20Hf0.20Nb0.40 High-Entropy Alloy

Metals

Gang Huang¹  Weiguang Zhang¹  Jian Zheng¹  Xiaosong Zhou¹  Huahai Shen¹  Sean Li²  Xiaotao Zu³  Jingxia Yu³  Haiyan Xiao³  Pengcheng Li³  Jutao Hu³  Xia Xiang³  Jianwei Zhang³ 

[1] Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, Mianyang 621900, China;School of Materials Science and Engineering, The University of New South Wales, Sydney, NSW 2074, Australia;School of Physics, University of Electronic Science and Technology of China, Chengdu 610054, China;

关键词: high-entropy alloys;    hydrogen storage;    sorption kinetics;    pressure–composition isotherm (PCI) curve;    XRD;   

DOI  :  10.3390/met11030470

来源: DOAJ

【 摘 要 】

High entropy alloys (HEAs) are composed of multiple main metal elements and have attracted wide attention in various fields. In this study, a novel Ti_0.20Zr_0.20Hf_0.20Nb_0.40 HEA was synthesized and its hydrogenation properties were studied, including sorption thermodynamics and hydrogen absorption/desorption kinetics. The maximum hydrogen absorption capacity was 1.5 H/atom at 573 K. X-ray diffraction (XRD) analysis indicated that the crystal structure of Ti_0.20Zr_0.20Hf_0.20Nb_0.40 HEA transformed from body-centered cubic (BCC) to body-centered tetragonal (BCT) with increasing hydrogen content, and to face-centered cubic (FCC) after hydrogen absorption to saturation. As a multi-principal element alloy, the Ti_0.20Zr_0.20Hf_0.20Nb_0.40 HEA possesses unique hydrogen absorption characteristics. The hydrogen absorption platform pressure rises gradually with the increase of the hydrogen absorption amount, which is caused by multiple kinds of BCT intermediate hydrides with consecutively increasing c/a. The full hydrogen absorption of the Ti_0.20Zr_0.20Hf_0.20Nb_0.40 HEA was completed in almost 50 s, which is faster than that of the reported hydrogen storage alloys in the literature. The experimental results demonstrate that the Ti_0.20Zr_0.20Hf_0.20Nb_0.40 HEA has excellent kinetic properties, unique thermodynamic hydrogen absorption performance, as well as a low plateau pressure at room temperature.

【 授权许可】

Unknown