A High-Throughput Computational Study on the Stability of Ni- and Ti-Doped Zr2Fe Alloys

Zr2Fe alloys have been widely used in fusion energy and hydrogen energy for hydrogen storage. However, disproportionation reactions occur easily in Zr-based alloys at medium and high temperatures, which greatly reduces the storage capacity of the alloys, and is not conducive to repeated cycle applications. The doping of Zr-based alloys with appropriate transition metal elements has been found to significantly improve their H storage properties and prevent hydrogen disproportionation. A convenient approach is required to efficiently predict the desirable doped structures that are physically stable with optimal properties. In this paper, based on the MatCloud High-Throughput Material Integrated Computing Platform (MatCloud), an automated process algorithm was established to solve the disproportionation reaction of Zr2Fe. Rather than testing the doping materials one by one, such high-throughput material screening is effective in reducing the computational time. The structural stability of modified Zr2Fe alloys, with different doping elements and doping concentrations, is systematically studied. The results indicate that the maximum doping concentration of Ni-doped Zr2Fe is 33 at%, and beyond this doping concentration, Zr-2(Fe1-xNix) phases become unstable. While Ti doping Zr2Fe will form a new phase, the overall hydrogen absorption capacity may have been affected by the decrease in the phase content of Zr2Fe in the main phase. The present study can shed valuable light on the design of high-performance Zr-based alloys for fusion energy and hydrogen storage.