石墨烯基-单（双）金属氧化物/氢氧化物复合材料的交流电电化学法一步制备及超电容性能研究

Graphene, a two-dimensional honeycomb sp2 carbon lattice, has been considered as one of the most appealing flexible electrode materials of supercapacitors. Mass production of high-quality, high-capacity graphene via a simple low cost method, however, remains a major challenge. In this program, high-quality graphene and graphene-based composite will be prepared efficiently via a green alternating voltage electrochemical approach that could provide the rapid alternate process of anodic oxidation and cathodic reduction. Various graphene and graphene-based composite materials (including metal or bimetallic oxides/graphene or non-mental doped-graphene composite, metal or double hydroxides/graphene or non-mental doped-graphene composite) with all kinds of characters can be obtained through changing combinations of working electrode, voltage, electrolyte, and other parameters. As a result, the controllable preparation of graphene and graphene-based composite materials will be reached.. Furthermore, the electrochemical mechanism of graphene and graphene-based composite materials prepared utilizing alternate voltage electrochemical approach, which can be studied by detecting the changes of the working electrode surface and electrolytic solutions, will be present in this program. In addition, the electrochemical characteristics of various kinds of graphene-based electrode materials will be investigated. With the introduction of non-metal element, metal or bimetallic oxides, metal or double hydroxides, the influence rules of improving the specific capacity of graphene will be also explored. Above all, the graphene-based composite materials with outstanding electrochemical properties will be obtained for supercapacitors. . The flexible asymmetrical solid-state supercapacitors will further be assembled utilizing as-prepared graphene-based electrode materials. The relationship between the constituent parts of electrode materials and their electrochemical performances will be discussed to clarify their contribution to energy storage. Moreover, the flexible asymmetrical solid-state supercapacitors with high energy density and excellent cycling stability will be designed through optimizing the structure of device. This project will provide reliable theoretical and technical support for the design and development of flexible supercapacitors utilizing graphene-based materials.

针对优质石墨烯制备困难、传统方法制备石墨烯的电化学电容比容量低的问题，本项目提出采用绿色交流电电化学法，利用其快速交替的阳极氧化和阴极还原过程，获得高效制备优质石墨烯的可控工艺条件，并通过改变电极的组合方式、交变电压、电解液等条件，获得杂原子掺杂石墨烯、石墨烯/掺杂石墨烯-单（双）金属氧化物/氢氧化物复合材料的制备工艺。在此基础上，研究电极种类、电解液组分等实验参数对所得材料微观结构的影响，监测交流电作用过程中电解液体系及电极表面的变化，揭示交流电电化学法制备石墨烯和石墨烯基复合材料的工作机制。进一步研究制备材料的电化学电容性能，阐明杂原子、单（双）金属氧化物/氢氧化物等赝电容材料对石墨烯电化学电容性能的影响，以获得优异性能的杂原子掺杂石墨烯和石墨烯基复合材料。从而利用制备的石墨烯基电极材料，构建柔性不对称固态超级电容器，优化器件的组装工艺，获得能量密度高、循环性能优异的柔性超级电容器。

实现能源的有效存储已成为发展新能源的关键，当前电化学储能被认为是理想的储能器件之一，并被广泛应用于交通运输、电网储能、航空航天以及便携式电子设备等领域。随着各种新储能设备的推出，探索低能耗、低污染、快速高效的材料生产新方法用以制备高性能、长寿命、环境友好的储能材料，是目前社会实现可持续发展的迫切需求。电化学方法具有绿色、室温、工艺灵活及效率高等优势，应用于构筑微/纳米级功能材料常表现出较高的可调控性。交流电电化学技术是一种新型的电化学分散法制备微纳米级功能材料的方法，本课题主要采用该技术设计构筑石墨烯、金属基材料及其复合材料，考察了所得材料的电化学形成机制及实验参数对材料形貌结构的影响规律，同时探究材料微观结构特征对其电化学性能的影响规律。主要研究结论如下：（1）在交流电作用下，利用电极表面交替的氧化还原过程，通过改变电解液组分，可获得少层石墨烯及N掺杂石墨烯材料，并发现电解液中阴、阳离子不同对剥离速率会有一定影响，所得N掺杂石墨烯在组装为对称型超级电容器后具有良好的循环性能，5000次循环后比容量可保持92.3%；（2）在交流电作用下，分别以Zn和Mo为电极，构筑了氧化锌纳米棒与石墨烯复合材料、薄片结构的二硫化钼与氮掺杂碳纳米管复合材料，探讨了不同电压及电解液组分对Zn及Mo电极表面的影响，揭示了材料的电化学形成过程，并发现所得复合材料内存在Zn-O-C，Mo-S-C等桥键，基于CV和EIS分析可知，复合后显著提升了材料的电导率及离子扩散速率；（3）基于复合材料强耦合作用的发现，以金属配合物为前驱体，进一步构筑了碳包覆结构的Cu9S5/NSC 和 ZnS/NSC复合材料，由于前驱体自身存在的S和N源，复合材料内存在更多的键合作用（C-S-Cu，C-S-Zn，S-O-Zn 等），使其表现出更优的电化学储能性能。本课题的相关研究成果扩展了交流电电化学技术的应用范围，为设计构筑柔性石墨烯基复合材料、强耦合作用的金属基复合材料提供一种新的思路和技术支持，并为开发获得高能量高功率密度的储能材料提供理论依据和技术支持。

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