论文部分内容阅读
通过在碱液中阴极还原铁酸铜(t-CuFe_2O_4)简便地实现了纳米Fe/Cu复合材料的自组装。采用循环伏安(CV)与X射线衍射(XRD)分析了自组装过程中的相变。通过透射电镜(TEM)、选区电子衍射(SAED)以及扫描透射-能谱分析(STEM-EDX)的表征可以发现电结晶得到的铁、铜纳米颗粒分布均匀且接触紧密。当用于铁镍电池负极时,Fe/Cu纳米复合电极展现了较好的放电容量与充电接收能力,并具备优异的高倍率与低温性能。当电流密度高达4 500 m A·g_(Fe)~(-1)或运行温度仅为-40℃时,该电极仍拥有很好的输出容量与电位特性。线性扫描伏安(LSV)分析证明了该电极中原位生成的Cu纳米颗粒催化了活性Fe的阳极溶解动力学性能,因而明显改善了电极的高倍率与低温放电性能。
The nano-Fe / Cu composites were easily assembled by cathodic reduction of copper ferrite (t-CuFe2O4) in alkaline solution. Phase transitions during self-assembly were analyzed by cyclic voltammetry (CV) and X-ray diffraction (XRD). Characterization by TEM, SAED and STEM-EDX showed that the electrocrystallized iron and copper nanoparticles were uniform and intimately contacted. When used in the negative electrode of Fe-Ni battery, the Fe / Cu nanocomposite electrode shows good discharge capacity and charge acceptance, and has excellent high-rate and low-temperature performance. When the current density reaches 4 500 m A · g_ (-1) or the operating temperature is only -40 ℃, the electrode still has good output capacity and potential characteristics. Linear sweep voltammetry (LSV) analysis demonstrated that the Cu nanoparticle formed in situ in the electrode catalyzed the anodic dissolution kinetics of the active Fe, thus significantly improving the high rate and low temperature discharge performance of the electrode.