Ti/Zr-based quasicrystals-formation,structure and hydrogen storage properties

摘要

Most common in Al-3d transition metal (TM) alloys,icosahedral quasicrystals (i-phase) are also found frequently in Ti/Zr-TM alloys.the Ti-TM-Si-O quasicrystals aqre metastable,produced only by rapid quenching,and are extremely disordered.In contrast,Ti-Zr-Ni i-phases are well ordered and stable,produced by relatively low temeprature annealing,nearly 300 deg C below the melting temperature.Important for both basic and practical reasons,Ti/Zr-based quasicrystals cna absorb significant quantities of hydrogen,up to two hydrogen atoms for each metal atom.the formaiton and sstructures of these quasicrystals and closely related complex crystal phases are discussed,The hydrogenation properties of these quasicrystals are presented and hsown to be competitive with mateirals in current use for hydrogen storage and battery applications.Results from recent studies usifng hydrogen as a probe of the local structure of the quasicrystal and crystal approximant are presented.