化工新型材料

化工新型材料 ›› 2019, Vol. 47 ›› Issue (7) : 174-177.

科学研究

复相La-Mg-Ti-Ni-Co基AB₃型储氢合金的相结构与电化学性能衰退机理研究

^1*

作者信息 +

Study on phase structure and electrochemical performance degradation mechanism of multiphase La-Mg-Ti-Ni-Co based AB₃ type hydrogen storage alloy

Dong Zhenwei¹, Xiong Haiyan², Shi Yichao¹, Gao Yuanhao¹

Author information +

文章历史 +

Received		Published
2017-12-29		2019-07-20
Issue Date	Revised Date
2019-08-05	2017-12-29

PDF (3168K)

摘要

研究了镧(La)-镁(Mg)-钛(Ti)-镍(Ni)-钴(Co)[La_0.7Mg_0.3-xTi_xNi_2.5Co_0.5(x=0～0.15)]储氢合金的相结构与电化学性能衰退机理。结果显示,合金的主相均为(La,Mg)Ni₃相,但随着Ti含量的增加,合金中逐渐产生了TiNi相而形成复相。合金经90次循环后的放电容量保持率从x=0条件下的56.5%增加至x=0.10条件下的62.0%,再下降至x=0.15条件下的60.8%,这与交换电流密度的变化规律一致。Ti对Mg的替代能够提高合金的耐蚀性,但过量的Ti会阻碍电极与电解液之间的界面反应,造成放电容量的衰退。

Abstract

The phase structures and electrochemical degradation mechanism of La_0.7Mg_0.3-xTi_xNi_2.5Co_0.5(x=0～0.15)hydrogen storage alloys were studied.The results showed that the main phase of the alloys was (La,Mg)Ni₃ phase,but TiNi phase was gradually formed in the alloys with the increase of Ti content.The discharge capacity retention rate of the alloys increased from 56.5% at x=0 to 62.0% at x=0.10,and then decreased to 60.8% at x=0.15 after 90 cycles,which was consistent with the change rule of exchange current density.The substitution of Ti for Mg could improve the corrosion resistance of the alloys,while excessive Ti hindered the interface reaction between electrodes and electrolyte,resulting in the decline of discharge capacities.

关键词

储氢合金 / 相结构 / 放电容量 / 循环性能

Key words

hydrogen storage alloy / phase structure / discharge capacity / cycle performance

引用本文

引用格式 ▾

复相La-Mg-Ti-Ni-Co基AB₃型储氢合金的相结构与电化学性能衰退机理研究[J]. 化工新型材料, 2019, 47(7): 174-177 DOI:

登录浏览全文

4963

注册一个新账户忘记密码

参考文献

原文顺序 | 出版日期 | 本文引用

[1] 李国辉,黄红霞,王新颖.AB₃型储氢合金的研究进展[J].化工新型材料,2015,43(9):1-3.
[2] 王新颖,黄红霞,谢文强,等.金属酞菁对新型La-Mg-Ni基储氢合金表面处理研究[J].化工新型材料,2017,45(6):183-185.
[3] Lim K L,Liu Y N,Zhang Q A,et al.Cycle stability of La-Mg-Ni based hydrogen storage alloys in a gas-solid reaction[J].International Journal of Hydrogen Energy,2017,42(37):23737-23745.
[4] Balcerzak M,Nowak M,Jurczyk M.Hydrogenation and electrochemical studies of La-Mg-Ni alloys[J].International Journal of Hydrogen Energy,2017,42(2):1436-1443.
[5] Li Y,Wang C X,Tao Y,et al.Effect of complex surface treatment on morphology and electrochemical properties of La-Mg-Ni-Based alloys[J].Journal of The Electrochemical Society,2017,164(12):A2611-A2616.
[6] Aybar A B,Anik M.Direct synthesis of La-Mg-Ni-Co type hydrogen storage alloys from oxide mixtures[J].Journal of Energy Chemistry,2017,26(4):719-723.
[7] Oesterreieher H,Cliton J,Bittner H.Hydrides of La-Ni compounds[J].Materials Research Bulletin,1976,11(10):1241-1247.
[8] Kadir K,Sakai T,Uehara I.Synthesis and structure determination of a new series of hydrogen storage alloys:RMg₂Ni₉ (R=La,Ce,Pr,Nd,Sm and Gd) built from MgNi₂ Laves-type layers alternating with AB₅ layers[J].Journal of Alloys and Compounds,1997,257(1/2):115-121.
[9] Kadir K,Kuriyama N,Sakai T,et al.Structural investigation and hydrogen capacity of CaMg₂Ni₉:a new phase in the AB₂C₉ system isostructural with LaMg₂Ni₉[J].Journal of Alloys and Compounds,1999,284(1/2):145-154.
[10] Kadir K,Sakai T,Uehara I.Structural investigation and hydrogen capacity of YMg₂Ni₉ and (Y_0.5Ca_0.5)(MgCa)Ni₉:new phases in the AB₂C₉ system isostructural with LaMg₂Ni₉[J].Journal of Alloys and Compounds,1999,287(1/2):264-270.
[11] Kadir K,Sakai T,Uehara I.Structural investigation and hydrogen storage capacity of LaMg₂Ni₉ and (La_0.65Ca_0.35)(Mg_l.32Ca_0.68)Ni₉ of the AB₂C₉ type structure[J].Journal of Alloys and Compounds,2000,302(1/2):112-117.
[12] Kohno T,Yoshida H,Kawashima F,et al.Hydrogen storage properties of new ternary system alloys:La₂MgNi₉,La₅Mg₂Ni₂₃,La₃MgNi_l4[J].Journal of Alloys and Compounds,2000,311:5-7.
[13] Jiang W Q,Lan Z Q,Xu L Q,et al.A study on the hydrogen-storage properties of La_2-xTi_xMgNi₉(x=0.1,0.2,0.3,0.4) alloys[J].International Journal of Hydrogen Energy,2009,34:4827-4832.
[14] 董振伟,马立群,王立民,等.Ti替代La对AB₃型储氢电极合金的结构与电化学性能的影响[J].南京工业大学学报科学版,2011,33(1):57-62.
[15] Dong Z W,Wu Y M,Ma L Q,et al.Influences of low-Ti substitution for La and Mg on the electrochemical and kinetic characteristics of AB₃-type hydrogen storage alloy electrodes[J].Science in China Series E(Technological Sciences),2010,1:242-247.
[16] Dong Z W,Wu Y M,Ma L Q,et al.Electrochemical properties of (La_1-xTi_x)_0.67Mg_0.33Ni_2.75Co_0.25(x=0-0.20,at%) hydrogen storage alloys[J].Materials Research Bulletin,2010,45:256-261.
[17] Kuriyama N,Sakai T,Miyamura H,et al.Electrochemical impedance spectra and deterioration mechanism of metal hydride electrodes[J].Journal of the Electrochemical Society,1992,139:L72-L76.