Ju Hui, Tang Qianqian, Xu Yong, Bai Xiaojing, Pu Chenjin, Liu Tongchen, Liu Shuxin, Zhang Lin
College of Chemistry and Chemical Engineering, Mianyang Teachers' College, Mianyang, 621900, China.
Research Centre of Laser Fusion, China Academy of Engineering Physics, Mianyang, 621900, China.
Dalton Trans. 2023 Sep 19;52(36):12948-12957. doi: 10.1039/d3dt01966g.
Supercapacitors (SCs) have been the subject of considerable interest because of their distinct advantages. The performance of SCs is directly affected by the electrode materials. Metal oxides derived from Prussian blue analogues (PBAs) are often used as electrode materials for SCs. Herein, we developed a multi-step strategy to fabricate ternary hollow metal oxide (CuO/NiO/CoO) heterostructures. The core-shell structured PBA (NiHCC@CuHCC) with Ni-based PBA (NiHCC) as the core and Cu-based PBA (CuHCC) as the shell was prepared by a crystal seed method. The ternary metal oxide (CuO/NiO/CoO) with a hollow structure was obtained by calcinating NiHCC@CuHCC. The prepared CuO/NiO/CoO demonstrates an excellent specific capacitance of 262.5 F g at 1 A g, which is 27.4% and 16.2% higher than those of CuO/CoO and NiO/CoO, respectively. In addition, the material showed outstanding cycling stability with a capacitance retention of 107.9% after 3000 cycles. The two-electrode system constructed with CuO/NiO/CoO and nitrogen-doped graphene hydrogel (NDGH) demonstrates a stable and high energy density of 27.1 W h kg at a power density of 1037.5 W kg. The capacitance retention rate was 100.7% after 4000 cycles. The reason for the excellent electrochemical properties could be the synergistic effect of the introduced heterojunction of CuO/NiO, the hollow structure, and various metal oxides. This strategy can greatly inspire the construction of SC electrodes.
超级电容器（SCs）因其独特的优势而备受关注。超级电容器的性能直接受电极材料影响。源自普鲁士蓝类似物（PBAs）的金属氧化物常被用作超级电容器的电极材料。在此，我们开发了一种多步策略来制备三元中空金属氧化物（CuO/NiO/CoO）异质结构。通过晶种法制备了以镍基普鲁士蓝类似物（NiHCC）为核、铜基普鲁士蓝类似物（CuHCC）为壳的核壳结构普鲁士蓝类似物（NiHCC@CuHCC）。通过煅烧NiHCC@CuHCC得到具有中空结构的三元金属氧化物（CuO/NiO/CoO）。制备的CuO/NiO/CoO在1 A g时表现出262.5 F g的优异比电容，分别比CuO/CoO和NiO/CoO高27.4%和16.2%。此外，该材料表现出出色的循环稳定性，3000次循环后电容保持率为107.9%。由CuO/NiO/CoO和氮掺杂石墨烯水凝胶（NDGH）构建的两电极系统在功率密度为1037.5 W kg时表现出27.1 W h kg的稳定高能量密度。4000次循环后电容保持率为100.7%。优异电化学性能的原因可能是引入的CuO/NiO异质结、中空结构和各种金属氧化物的协同效应。该策略可极大地启发超级电容器电极的构建。
