State Key Laboratory of Silicon Materials, Department of Materials Science and Engineering, Zhejiang University, Hangzhou, 310027, P. R. China.
Nanoscale. 2013 Oct 7;5(19):9134-40. doi: 10.1039/c3nr02737f. Epub 2013 Aug 5.
CuO nanosheets (NSs)/reduced graphene oxide (rGO) hybrid lamellar films were prepared by vacuum filtration of CuO NSs/GO composite dispersions, followed by hydrothermal reduction. The CuO NSs/GO composite dispersions were assembled electrostatically by mixing a negatively charged GO sheets aqueous solution with a positively charged CuO NSs aqueous dispersion at room temperature. The prepared CuO NSs/rGO hybrid lamellar films exhibited a specific capacitance of 163.7 F g(-1), which is much higher than the 69.7 F g(-1) of CuO NSs and 66.0 F g(-1) of rGO. The effective specific capacitance was 82.5 F g(-1) after 1000 cycles, which was more than two times the 32.7 F g(-1) of CuO NSs electrodes. The synergistic redox activity of the CuO NSs, in combination with the high electronic conductivity of the rGO and the unique CuO NSs spaced sandwich-like porous structures, dominated the excellent capacitance of CuO NSs/rGO hybrid lamellar films. The sandwiched, lamellar, porous structures not only provide plenty of paths for electrolyte-ion access to the CuO NSs but also expose the rGO sheets to the electrolyte as much as possible. This process provides a potential way to synthesise metal oxide/GO composite electrodes for capacitors.
CuO 纳米片（NSs）/还原氧化石墨烯（rGO）杂化层状薄膜是通过真空过滤 CuO NSs/GO 复合分散体，然后进行水热还原制备的。CuO NSs/GO 复合分散体通过在室温下将带负电荷的 GO 片水溶液与带正电荷的 CuO NSs 水溶液混合而静电组装。所制备的 CuO NSs/rGO 杂化层状薄膜表现出 163.7 F g(-1) 的比电容，比 CuO NSs 的 69.7 F g(-1) 和 rGO 的 66.0 F g(-1) 都要高。经过 1000 次循环后，有效比电容为 82.5 F g(-1)，是 CuO NSs 电极的 32.7 F g(-1) 的两倍多。CuO NSs 的协同氧化还原活性，结合 rGO 的高导电性和独特的 CuO NSs 间隔三明治状多孔结构，主导了 CuO NSs/rGO 杂化层状薄膜的优异电容性能。夹在中间的层状多孔结构不仅为电解质离子进入 CuO NSs 提供了大量的通道，而且尽可能地使 rGO 片暴露在电解质中。该过程为合成用于电容器的金属氧化物/GO 复合电极提供了一种潜在的方法。
