Self-assembly of free-standing hybrid film based on graphene and zinc oxide nanoflakes for high-performance supercapacitors
Self-assembly of free-standing hybrid film based on graphene and zinc oxide nanoflakes for high-performance supercapacitors
复制标题
DOI：
10.1016/j.jssc.2019.06.003
复制
发表时间：
2019-09
影响因子：
3.3
通讯作者：
Xiangxiang Du;Shan Wang;Yingchun Liu;Maoping Lu;Kun Wu;Mangeng Lu
中科院分区：
文献类型：
--
作者：
Xiangxiang Du;Shan Wang;Yingchun Liu;Maoping Lu;Kun Wu;Mangeng Lu
采用易过滤自组装和热还原法制备了以石墨烯和氧化锌纳米片为电极材料的独立杂化膜。将制备好的ZnO纳米片插入到石墨烯片中，形成独特的层-层结构。该杂化膜可直接用作超级电容器的无粘结剂自支撑电极材料。在扫描速率为5 mV s−1时，制备的氧化锌纳米片/还原氧化石墨烯（ZnO/rGO） SCs的最大比电容高达167.2 F g−1，比纯氧化石墨烯（111.4 F g−1）高出近50%，是ZnO纳米片（71.1 F g−1）的两倍多。电化学性能的提高可能是由于电活性氧化锌纳米片和高导电性石墨烯片网络的有效利用以及它们之间良好的协同效应。独立混合膜还表现出良好的循环能力，在2000次循环后，初始容量保持在90%以上。EIS分析表明，复合材料的电阻较低，提高了工作电极的离子扩散能力和表面电荷转移性能。它具有高性能电化学储能应用的潜力。
A free-standing hybrid film combining graphene and zinc oxide nanoflakes used as electrode materials was prepared by facile filtration self-assembly and thermal reduction process. The as-prepared ZnO nanoflakes were inserted into the graphene sheets to form unique layer-layer structure. The hybrid film can be directly employed as binder-free and self-supported electrode material for supercapacitors (SCs). The max specific capacitance of fabricated zinc oxide nanoflakes/reduced graphene oxide (ZnO/rGO) SCs is as high as 167.2 F g−1at a scan rate of 5 mV s−1, which is nearly 50% higher than pure rGO (111.4 F g−1) and more than twice as much as ZnO nanoflakes (71.1 F g−1). The enhanced electrochemical performance could be due to the efficient utilization of electroactive ZnO nanoflakes and high conductive graphene sheets network and the good synergistic effect between them. The free-standing hybrid film also exhibits an excellent cycling capability, retention of the initial capacity over 90% after 2000 cycles. The EIS analysis of the hybrids showed low electrical resistance, improving ion diffusion capacity and surface charge transfer performance of the working electrode. It holds a potential for high performance electrochemical energy storage applications.