Zhou Yang, Guo Lei, Shi Wei, Zou Xuefeng, Xiang Bin, Xing Shaohua
School of Chemistry and Chemical Engineering, Chongqing University, Chongqing 400044, China.
School of Material and Chemical Engineering, Tongren University, Tongren 554300, China.
Materials (Basel). 2018 May 24;11(6):881. doi: 10.3390/ma11060881.
Benefiting from good ion accessibility and high electrical conductivity, graphene-based material as electrodes show promising electrochemical performance in energy storage systems. In this study, a novel strategy is devised to prepare binder-free Mn₃O₄-reduced graphene oxide (Mn₃O₄/rGO) electrodes. Well-dispersed and homogeneous Mn₃O₄ nanosheets are grown on graphene layers through a facile chemical co-precipitation process and subsequent flame procedure. This obtained Mn₃O₄/rGO nanostructures exhibit excellent gravimetric specific capacitance of 342.5 F g at current density of 1 A g and remarkable cycling stability of 85.47% capacitance retention under 10,000 extreme charge/discharge cycles at large current density. Furthermore, an asymmetric supercapacitor assembled using Mn₃O₄/rGO and activated graphene (AG) delivers a high energy density of 27.41 Wh kg and a maximum power density of 8 kW kg. The material synthesis strategy presented in this study is facile, rapid and simple, which would give an insight into potential strategies for large-scale applications of metal oxide/graphene and hold tremendous promise for power storage applications.
得益于良好的离子可及性和高导电性,基于石墨烯的材料作为电极在储能系统中展现出了有前景的电化学性能。在本研究中,设计了一种新颖的策略来制备无粘结剂的Mn₃O₄-还原氧化石墨烯(Mn₃O₄/rGO)电极。通过简便的化学共沉淀过程及后续的火焰处理,在石墨烯层上生长出了分散良好且均匀的Mn₃O₄纳米片。所制备的Mn₃O₄/rGO纳米结构在1 A g的电流密度下展现出342.5 F g的优异比电容,并且在大电流密度下进行10000次极限充放电循环后,具有85.47%的电容保持率,展现出卓越的循环稳定性。此外,使用Mn₃O₄/rGO和活性石墨烯(AG)组装的非对称超级电容器具有27.41 Wh kg的高能量密度和8 kW kg的最大功率密度。本研究中提出的材料合成策略简便、快速且简单,这将为金属氧化物/石墨烯大规模应用的潜在策略提供见解,并在储能应用方面具有巨大的潜力。