TiZrNi准晶电化学储氢性能研究

Electrochemical Hydrogen Storage Property of TiZrNi Quasicrystal

准晶是一种结构特殊的固态有序相。其特殊的原子排列方式可能会使其具有较高的储氢性能。研究目的是获得Ti系准晶,并对其电化学储氢性能进行研究。采用铸造法炼制合金,准晶难以形成。因此采用首先通过机械合金化获得非平衡态合金,然后对非平衡态合金进行不同温度热处理来获得准晶的技术路线。采用机械合金化制备了Ti42.5Zr42.5Ni15非晶。在机械合金化过程中要注意气体保护,否则难以形成非晶。将非晶合金在530℃处理2 h后,在基体中出现了准晶,此时的基体为准晶和晶态混合物,准晶占大部分。经750℃处理2 h后,合金基体中只有晶态存在。对不同状态合金进行了电化学储氢特性测量。对于非晶、准晶、晶态三状态合金,其电化学储氢均存在一个活化过程。非晶态的容量最高,其次为准晶态,晶态最低。

Quasicrystal was a kind of special solid ordered phase.Its particular atom arrangement made it have good hydrogen storage property.Preparation of Ti base quasicrystal and its electrochemical hydrogen storage property were studied.The quasicrystal alloy could be prepared by annealing nonequilibrium alloy at different temperature with nonequilibrium alloy acquired by mechanical alloying.Amorphous Ti42.5Zr42.5Ni15 alloy was prepared by mechanical alloying.During the process of mechanical alloying,special protecting method was adopted so as to get amorphous alloy.Quasicrystal phase formed after treating Ti42.5Zr42.5Ni15 amorphous alloy at 530 ℃ for 2 h.At this state,the matrix was composed of quasicrystal and crystalline phase,quasicrystal was the main phase.After treated at 750 ℃ for 2 h,there was only crystalline phase left.The electrochemical hydrogen storage of TiZrNi with different state was studied.For the alloy under different state,such as amorphous,quasicrystal and crystalline state,there existed an activating process of electrochemical hydrogen storage.For the hydrogen storage capacity of three kinds of alloys,from high to low,the sequence was amorphous state,quasicrystal state and crystal state.