Yang Chongyang, Sun Minqiang, Lu Hongbin
State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Collaborative Innovation Center of Polymers and Polymer Composites, Fudan University, 2005 Songhu Road, Shanghai, 200438, P. R. China.
Chemistry. 2018 Apr 20;24(23):6169-6177. doi: 10.1002/chem.201800074. Epub 2018 Apr 6.
Metal oxides have great potential for developing high-performance supercapacitors due to their high specific capacitances. However, achieving high energy densities while maintaining good rate capability and long cycle life has proved to be challenging. We propose herein a strategy for constructing all-metal-oxide asymmetric supercapacitors (ASCs), in which both the cathode and anode are based on metal oxides, and demonstrate their outstanding electrochemical performance. We anchored SnO nanoparticles on the surface of reduced graphene oxide (RGO) through Sn-O-C bonds (as the cathode of ACSs), and employed low-crystalline RGO/MoO nanosheets as the anode, based on the large work function difference between SnO and MoO . The resulting ASC can operate stably at 1.8 V in neutral aqueous electrolyte and deliver an energy density of up to 33 W h kg , which remains at 13.8 W h kg even at 37.5 kW kg . Moreover, the ASC exhibits a good cycling stability of 92.5 % capacitance retention after 20 000 cycles.
金属氧化物因其高比电容在开发高性能超级电容器方面具有巨大潜力。然而，在保持良好倍率性能和长循环寿命的同时实现高能量密度已被证明具有挑战性。我们在此提出一种构建全金属氧化物不对称超级电容器（ASC）的策略，其中阴极和阳极均基于金属氧化物，并展示了它们出色的电化学性能。我们通过Sn - O - C键将SnO纳米颗粒锚定在还原氧化石墨烯（RGO）表面（作为ASC的阴极），并基于SnO和MoO之间的大的功函数差，采用低结晶度的RGO/MoO纳米片作为阳极。所得的ASC在中性水电解质中可在1.8 V下稳定运行，能量密度高达33 W h kg，即使在37.5 kW kg时仍保持在13.8 W h kg。此外，该ASC在20000次循环后表现出良好的循环稳定性，电容保持率为92.5％。
