摘要
High density and safe storage of hydrogen are the preconditions for the large-scale application of hydrogen energy.Herein,the hydrogen storage properties of Ti_(0.6)Zr_(0.4)Cr_(0.6)Mn_(1.4) alloys are systematically studied by introducing Y element instead of Ti element through vacuum arc melting.After the partial substitution of Y,a second phase of rare earth oxide is added in addition to the main suction hydrogen phase,C14 Laves phase.Thanks to the unique properties of rare earth elements,the partial substitution of Y can not only improve the activation properties and plateau pressure of the alloys,but also increase the effective hydrogen storage capacity of the alloys.The comprehensive properties of hydrogen storage alloys are improved by multidimensional regulation of rare earth elements.Among them,Ti_(0.552)Y_(0.048)Zr_(0.4)Cr_(0.6)Mn_(1.4) has the best comprehensive performance.The alloy can absorb hydrogen without activation at room temperature and 5 MPa,with a maximum hydrogen storage capacity of 1.98 wt.%.At the same time,it reduces the stability of the hydride and the enthalpy change value,making it easier to release hydrogen.Through theoretical analysis and first-principle simulation,the results show that the substitution of Y element reduces the migration energy barrier of hydrogen and the structural stability of the system,which is conducive to hydrogen evolution.The alloy has superior durability compared to the original alloy,and the capacity retention rate was 96.79%after 100 hydrogen absorption/desorption cycles.
基金
supported by the Major Science and Technology Project of Inner Mongolia(No.2021ZD0029)
the National Natural Science Foundation of China(No.52301295)
Key R&D projects of Jilin Provincial Science and Technology Development Plan(No.20230201125GX)
Special fund of Scientific and Technological Cooperation Program between Jilin Province and Chinese Academy of Sciences(No.2023SYHZ0031)
the Youth Innovation Promotion Association CAS(No.2022225)
Guangdong Provincial University Innovation Team Project(No.2023KCXTD038)
the State Key Laboratory of Rare Earth Resources Utilization(No.110000RL86)
Changchun Institute of Applied Chemistry.
