用感应熔炼方法熔炼A5B19型La0.68Gd0.2Mg0.12Ni3.3CoO．3A10.1合金，并在密闭容器中对合金进行不同温度（1173-1273K）下保温16h的热处理，采用电感耦合等离子发射光谱（ICP）、X射线衍射（XRD）、电子探针显微分析方法（EPMA）和电化学测试分析方法对比研究了退火温度对合金成分、微观组织和电化学性能的影响。结果表明，A5B19型合金组织主要由Ce5C019（Pr5Co19）型、PuNi3型和Ca-Cu5型等相组成，退火后舍金则形成以A5B19型（Pr5Co19和Ce5Co19）为主相的多相组织，随退火温度升高Pr5Co19型主相的相丰度逐渐增加，当T=1273K时其相丰度达到最大值87．8％（质量分数），而Ce5Co19型相仅为0．78％（质量分数）。电化学分析测试表明，退火温度对合金电极的活化性能和大电流放电特性影响不明显，但对电极容量和循环稳定性影响较大。在T=1273K退火后，合金电极放电容量为373．01mAh／g，经100次充放电循环后其电极容量保持率（S100）为90．20％，表现出较好的电化学性能。
La0.68Gd0.2Mg0.12Ni3.3CoO.3A10.1 hydrogen storage alloys were prepared by induction melting and then annealed at different temperature(1173-1273K) in the closed container for 16h. The effect of annealing tempera- ture on the microstructure and electrochemical properties of La0.68Gd0.2Mg0.12Ni3.3CoO.3A10.1 were investigated by means of inductively coupled plasma(ICP), X-ray diffraction (XRD), electron probe micro-analysis (EP MA) and electrochemical measurements. The results showed that the A5B19 alloys mainly consisted of Ce5Co19- type(Pr5Co19-type), PuNi3-type and CaCus-type phase. Meanwhile, with increasing annealing temperature, Pr5Co19-type phase abundance in annealed alloys increased, and CesCo19 type phase abundance decreased. The Pr5Co19-type phase abundance was 87.75wt%, andCe5Co19-type phase abundance was only 0.78wt% when an- nealing temperature was 1273K. The electrochemical measurements showed that these alloys had little effects on activation performance under different annealing temperature, but it was great impact on electrode capacity and cycle stability. The discharge capacity of the alloys reached 373. 01mAh/g when annealing temperature was 1273K. After 100 charge-discharge cycles, the discharge capacity retention rate(S100)of the alloy electrode(T= 1273K) reached 90.2%.
参考文献
| [1] | Liu Yongfeng;Cao Yanhui;Li Huang et al.Rare earth- Mg-Ni-based hydrogen storage alloys as negative electode materials for Ni/MH batteries[J].Journal of Alloys and Compounds,2011,509(03):675686. |
| [2] | Kadir K;Kuriyama N;Sakai T et al.Structural investi gation and hydrogen capacity of CaMgz Ni9:a new phase in the AB2C9,system isostructural with LaMgNi9[J].Journal of Alloys and Compounds,1999,284(1-2):145-154. |
| [3] | Kadir K;Sakai T;Uehara I .Structural investigation and hydrogen storage capacity of LaMg2 Ni9 and(La0.s5 Ca0.35)(Mgl.32 Cao.68)Ni9 of AB2 C9,type structure[J].Journal of Alloys and Compounds,2000,302(1-2):112117. |
| [4] | Kohno T.;Yoshida H. .Hydrogen storage properties of new ternary system alloys: La_2MgNi_9, La_5Mg_2Ni_(23), La_3MgNi_(14)[J].Journal of Alloys and Compounds: An Interdisciplinary Journal of Materials Science and Solid-state Chemistry and Physics,2000(2):L5-L7. |
| [5] | Hayakawa H;Akiba E;Kohno T .Crystal structures of novel La-Mg-Ni hydrogen absorbing alloys[J].Journal of Alloys and Compounds,2005,408-412:280-283. |
| [6] | Hayakawa H;Akiba E;Gotoh M et al.Crystal struc tures of La-Mg-Ni,(x= 3-4)system hydrogen torage al- loys[J].Materials Transactions,2005,69(01):170-178. |
| [7] | Okamoto H .La Ni(lanthanum nickel)[J].Phase Equi libria,1991,12(05):615-616. |
| [8] | Wang Dahul;Luo Yongchun;Yan Ruxu et al.Phase structure and electrochemical properties of Lao.67Mgo.:a- Ni3.o,Co,Cr=0,0.25,0.5,0.75)hydrogen storage al- loys[J].Journal of Alloys and Compounds,2006,413(1/2):193-197. |
| [9] | Ozaki T;Kanemoto M;Kakeya T et al.Stacking struc- tures and electrode performances of rare earthe Mg Ni based alloys for advanced nickele metal hydride battery[J].Journal of Alloys and Compounds,2007,446-447:620-624. |
| [10] | 周增林,宋月清,黄长庚,崔舜,张永健,李学军,黄倬.热处理对La0.7Mg0.3（Ni0.85Co0.15）3.4贮氢电极合金性能的影响[J].西安交通大学学报,2007(11):1373-1379. |
| [11] | 瞿鑫鑫,马立群,金传伟,赵相玉,丁毅.氟化处理对La0.67Mg0.33Ni2.25Co0.75贮氢合金电化学性能的影响[J].稀有金属材料与工程,2011(03):543-546. |
| [12] | Eerey A;Cuevas F;Latroche M et al.Elaboration and characterization of magnesium substituted LaaNi19 hy-dride forming alloys as active materials for negative elec- trode in Ni -MH battery[J].Electrochimica Acta,2009,54:1710-1714. |
| [13] | Z.Y. Liu;X.I. Yan;N. Wang;Y.J. Chai;D.I. Hou .Cyclic stability and high rate discharge performance of (La,Mg)_5Ni_(19) multiphase alloy[J].International journal of hydrogen energy,2011(7):4370-4374. |
| [14] | Zhang Qingan;Fang Niaohui;Si Tingzhi et al.Phase stability,structural transition,and hydrogen absorption desorption features of the polymorphic La1 MgNi19 com- pound[J].The Journal of Physical Chemistry C,2010,114(26):11686-11692. |
| [15] | 陈江平,罗永春,张法亮,阎汝煦,康家晨,陈剑虹.退火处理对La1.5Mg0.5Ni7.0贮氢合金相结构和电化学性能的影响[J].稀有金属材料与工程,2006(10):1572-1576. |
| [16] | Yasuoka S;Magari Y;Murata T et al.Development of high capacity nickel metal hydride batteries using super- lattice hydrogen-absorbing alloys[J].Journal of Power Sources,2006,156(02):662-666. |
| [17] | Li Rongfeng;Kang Long;Luo Yongchun et al.The impact of heat treatment on La0.63 Gd0.z Mg0.lr Ni3.1 Coo.3 A10.1 hydrogen storage alloy microstructure and electro- chemical properties[J].Journal of the Chinese Society of Rare Earths,2011,29(05):558-606. |
| [18] | Gao Zhijie;Kang Long;Luo Yongchun.Influence of magnesium content on structure and performance of A2 B7 type R Mg-Ni hydrogen storage alloys[J].Chemi- cal Journal of Chinese Universities |
| [19] | Young R A.The rietveld method[M].London,Oxford:Oxford University Press,1995 |
| [20] | Ma Lidun.Neoteric X-ray polycrystalline diffraction[M].北京:化学工业出版社,2004:399-408. |
| [21] | Zhang Di;Yamamoto T;Inui H et al.Characterization of stacking faults on based planes in intermetaltic com- pounds LasNi19 and La2Ni7[J].Intermetallics,2000,8(04):391-397. |
| [22] | Y.J. Chai;K. Sakaki;K. Asano .Crystal structure and hydrogen storage properties of La-Mg-Ni-Co alloy with superstructure[J].Scripta materialia,2007(6):545-548. |
| [23] | Li F;Young K;Ouchi T .Annealing effects on structur al and electrochemical properties of(LaPrNdZr)0.83 Mg0.1v(NiCoA1Mn)3a alloy[J].Journal of Alloys and Compounds,2009,471(1-2):371-377. |
| [24] | Yuan Xianxia;Xu Naixin .Hydrogen diffusion in the electrochemical study of the behavior of rare earth based ABs-type hydrogen storage alloy electrode[J].Rare Metal Materials and Engineering,2003,32(01):2731. |
- 下载量()
- 访问量()
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%