Novel electrode materials with desired specific capacitances are needed for supercapacitors. Rare earth (RE)-based materials are fascinating in the field of catalysis and energy. Herein, a series of hydroxides including La, Ce, Pr and Nd was synthesized via in situ precipitation. Interestingly, only Ce(OH)3 showed redox peak in positive and negative range. The other RE hydroxides exhibited redox peak only in positive range. Therefore, in order to certify Ce(OH)3 can be used as negative electrode, symmetrical supercapacitors consisting of Ce(OH)3 as positive and negative electrode were assembled, showing a voltage window of 1.3 V. Moreover, asymmetrical supercapacitors were successfully fabricated, in which positive electrode were composed of La(OH)3, Pr(OH)3 and Nd(OH)3, respectively. These results may pave a way for novel negative electrode materials in energy field.

中文翻译：

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Ce(OH)3作为新型超级电容器负极材料

超级电容器需要具有所需比电容的新型电极材料。稀土 (RE) 基材料在催化和能源领域极具吸引力。在此，通过原位沉淀合成了包括La、Ce、Pr和Nd在内的一系列氢氧化物。有趣的是，只有 Ce(OH)3 在正负范围内显示出氧化还原峰。其他稀土氢氧化物仅在正范围内表现出氧化还原峰。因此，为了证明Ce(OH)3可以用作负极，组装了由Ce(OH)3作为正极和负极组成的对称超级电容器，电压窗口为1.3 V。此外，成功制造了非对称超级电容器，其中正极分别由 La(OH)3、Pr(OH)3 和 Nd(OH)3 组成。