Li Mai, Zhu Kailan, Meng Zheyi, Hu Ruihua, Wang Jiale, Wang Chunrui, Chu Paul K
College of Science, Donghua University Shanghai 201620 China
State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Material Science, Donghua University Shanghai 201620 China
RSC Adv. 2021 Nov 4;11(57):35726-35736. doi: 10.1039/d1ra05742a.
Recent research and development of energy storage devices has focused on new electrode materials because of the critical effects on the electrochemical properties of supercapacitors. In particular, MnO and FeO have drawn extensive attention because of their low cost, high theoretical specific capacity, environmental friendliness, and natural abundance. In this study, MnO ultrathin nanosheet arrays and FeO nanoparticles are fabricated on TiN nanowires to produce binder-free core-shell positive and negative electrodes for a flexible and ultra-fast hybrid supercapacitor. The MnO/TiN/CC electrode shows larger pseudocapacitance contributions than MnO/CC. For example, at a scanning rate of 2 mV s, the pseudocapacitance contribution of MnO/TiN/CC is 87.81% which is nearly 25% bigger than that of MnO/CC (71.26%). The supercapacitor can withstand a high scanning rate of 5000 mV s in the 2 V window and exhibits a maximum energy density of 71.19 W h kg at a power density of 499.79 W kg. Even at 5999.99 W kg, it still shows an energy density of 31.3 W h kg and after 10 000 cycles, the device retains 81.16% of the initial specific capacitance. The activation mechanism is explored and explained.
由于对超级电容器的电化学性能有至关重要的影响，储能设备的近期研发工作聚焦于新型电极材料。特别是MnO和FeO，因其成本低、理论比容量高、环境友好以及天然丰度高而受到广泛关注。在本研究中，在TiN纳米线上制备了MnO超薄纳米片阵列和FeO纳米颗粒，以生产用于柔性超快混合超级电容器的无粘结剂核壳正负极。MnO/TiN/CC电极比MnO/CC表现出更大的赝电容贡献。例如，在扫描速率为2 mV s时，MnO/TiN/CC的赝电容贡献为87.81%，比MnO/CC（71.26%）高出近25%。该超级电容器在2 V窗口内可承受5000 mV s的高扫描速率，在功率密度为499.79 W kg时表现出71.19 W h kg的最大能量密度。即使在5999.99 W kg时，它仍显示出31.3 W h kg的能量密度，并且在10000次循环后，该器件保留了初始比电容的81.16%。对其活化机制进行了探索和解释。
