用快淬技术制备了Mg2Ni型贮氢合金,合金的名义成分为Mg20-xLaxNi10(x=0,2,4,6).用XRD、SEM、HRTEM分析了合金的微观结构.发现不含La的快淬合金中没有非晶相,但含La快淬合金中显示以非晶相为主.当La含量x≤2时,铸态合金的主相为Mg2Ni相,但随着La含量的进一步增加,铸态合金的主相改变为(La,Mg)Ni3+LaMg3相.应用Sieverts设备研究了铸态及快淬态合金的吸放氢量及动力学,结果表明,x=2的合金吸放氢量及动力学随淬速的增加而增加,但对于x=6的合金,结果是相反的.电化学测试结果表明,x=2合金的放电容量随淬速的增加而增加,而对于x=6合金,结果也是相反的.快淬显著地提高了x=2,6合金的循环稳定性.
Mg2Ni-type hydrogen storage alloys with nominal composition Mg20-xLaxNi10 (x = 0, 2, 4, 6) were prepared by melt spinning. The microstructures of the alloys were studied by XRD, SEM and HRTEM. It is found that no amorphous phase formed in the as-spun La-free alloy, but the as-spun alloys containing La mainly held a major amorphous phase. When La content x≤2, the major phase in the as-cast alloys is Mg2Ni phase, but with the further increase of La content, the major phase of the as-cast alloys changes into (La,Mg)Ni3+LaMg3 phases. The hydrogen absorption and desorption kinetics of the as-cast and spun alloys were measured using an automatically controlled Sieverts apparatus, indicating that the hydrogen absorption and desorption capacity and the kinetics of the x=2 alloy clearly increase with rising of spinning rate, but a contrary result is obtained for x = 6 alloy. The electrochemical measurement shows that the discharge capacity of the x = 2 alloy grows with rising of spinning rate, but it is a completely contrary result for x = 6 alloy. The melt spinning significantly improves the cycle stability of the x = 2 and 6 alloys.
参考文献
| [1] | Woo J H;Lee K S .[J].Journal of the Electrochemical Society,1999,146(03):819. |
| [2] | Liu F J;Suda S .[J].Journal of Alloys and Compounds,1995,231:742. |
| [3] | Liu YN.;Zhang XJ. .Effect of lanthanum additions on electrode properties of Mg2Ni[J].Journal of Alloys and Compounds: An Interdisciplinary Journal of Materials Science and Solid-state Chemistry and Physics,1998(1/2):231-234. |
| [4] | Nohara S.;Zhang SG.;Inoue H.;Iwakura C.;Fujita N. .Electrochemical characteristics of a homogeneous amorphous alloy prepared by ball-milling Mg2Ni with Ni[J].Journal of Alloys and Compounds: An Interdisciplinary Journal of Materials Science and Solid-state Chemistry and Physics,1998(1/2):76-78. |
| [5] | Kimura H;Masumoto T .[J].Scripta Metallurgica,1975,9:211. |
| [6] | Huang L J;Liang G Y;Sun Z B et al.[J].Journal of Power Sources,2006,160:684. |
| [7] | Yamaura S I;Kim H Y;Kimura H et al.[J].Journal of Alloys and Compounds,2002,339:230. |
| [8] | Teresiak A;Gebert A;Savyak M et al.[J].Journal of Alloys and Compounds,2005,398:156. |
| [9] | Hammioui M E;Belkbir L;Gerard N Z .[J].Physical Chemistry,1992,178:207. |
| [10] | Goo N H;Woo J H;Lee K S .[J].Journal of Alloys and Compounds,1999,288:286. |
| [11] | Wang L B;Tang Y H;Wang Y J et al.[J].Journal of Alloys and Compounds,2002,336:297. |
| [12] | Jiang J J;Gasik M .[J].Journal of Power Sources,2000,89(01):117. |
| [13] | Zhang Y H;Li B W;Ren H P et al.[J].International Journal of Hydrogen Energy,2007,32:4627. |
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