Enhanced electrochemical properties of LaFeO3 with Ni modification for MH-Ni batteries
Enhanced electrochemical properties of LaFeO3 with Ni modification for MH-Ni batteries
复制标题
Ni改性LaFeO3增强MH-Ni电池的电化学性能
DOI：
10.1007/s12613-018-1672-x
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发表时间：
2018
影响因子：
4.8
通讯作者：
Han Shu-min
中科院分区：
文献类型：
--
作者：
Dong Zhen-tao;Li Yuan;Ren Kai-liang;Yang Shu-qin;Zhao Yu-meng;Yuan Yong-jie;Zhang Lu;Han Shu-min
在本研究中，我们在la2o3和Fe2O3的反应物中加入Ni，采用固相法合成了LaFeO3-xwt %Ni （x = 0,5,10,15）复合材料。场发射扫描电镜（FE-SEM）和能量色散x射线能谱分析（EDS）结果表明，Ni粉末均匀分散在lafeo3颗粒中，明显降低了lafeo3颗粒的聚集，使复合材料具有松散的结构。此外，Ni形成了导电网络，从而提高了复合材料的导电性。lafeo3电极的最大放电容量从266.8 mAh·g-1 （x = 0）显著增加到339.7 mAh·g-1 （x = 10）。特别是在1500 mA·g−1的放电电流密度下，LaFeO3 - 10wt%Ni电极的高倍率放电率达到54.6%，是纯LaFeO3的1.5倍左右。这种ni修饰的松散结构不仅提高了LaFeO3颗粒表面的电荷转移速率，而且提高了氢在LaFeO3体中的扩散速率。
In this work, we synthesized LaFeO3–xwt%Ni (x = 0, 5, 10, 15) composites via a solid-state reaction method by adding Ni to the reactants, La2O3and Fe2O3. Field-emission scanning electron microscopy (FE-SEM) and energy-dispersive X-ray spectroscopy (EDS) results revealed that Ni powders evenly dispersed among the LaFeO3particles and apparently reduced their aggregation, which imparted the composites with a loose structure. Moreover, the Ni formed a conductive network, thus improving the conductivity of the composites. The maximum discharge capacity of the LaFeO3electrodes remarkably increased from 266.8 mAh·g–1(x = 0) to 339.7 mAh·g–1(x = 10). In particular, the high-rate dischargeability of the LaFeO3–10wt%Ni electrode at a discharge current density of 1500 mA·g−1reached 54.6%, which was approximately 1.5 times higher than that of the pure LaFeO3. Such a Ni-modified loose structure not only increased the charge transfer rate on the surface of the LaFeO3particles but also enhanced the hydrogen diffusion rate in the bulk LaFeO3.