Tan Qingke, Kong Zhen, Guan Xianggang, Zhang Lian Ying, Jiao Zhengbo, Chen Hai Chao, Wu Guanglei, Xu Binghui
Institute of Materials for Energy and Environment, College of Materials Science and Engineering, Qingdao University, Qingdao 266071, China.
Institute of Materials for Energy and Environment, College of Materials Science and Engineering, Qingdao University, Qingdao 266071, China; State Key Laboratory of Bio-Fibers and Eco-Textiles, Qingdao University, Qingdao 266071, China.
J Colloid Interface Sci. 2019 Jul 15;548:233-243. doi: 10.1016/j.jcis.2019.04.041. Epub 2019 Apr 15.
A novel and simple approach to preparing hierarchical zinc oxide/reduced graphene oxide (ZnO/RGO@RGO) composite is demonstrated using few-layered graphene oxide (GO) and metal zinc as starting materials following combined processes, including in-situ metal zinc reduction and catalyzed GO deoxygenation. Metal zinc can directly reduce GO sheets in aqueous GO suspension at room temperature to obtain a porous composite precursor (ZnO/RGO) with ZnO nanoparticles anchored on the RGO sheets. Then another RGO protecting layer is directly coated on the ZnO/RGO precursor to obtain the hierarchical ZnO/RGO@RGO composite. In this step, the exposed ZnO nanoparticles on the surface of ZnO/RGO play the role of catalyst to accelerate the deoxygenation of GO from the extra added GO aqueous suspension under mild hydrothermal condition. The reaction mechanism of metal zinc with GO aqueous suspension has been explored and the catalyst role of ZnO has been verified in this work. The prepared ZnO/RGO@RGO composite exhibited both stable cycling performance and good rate capability as anode for lithium-ion batteries. The method to prepare ZnO/RGO composite is economic and eco-friendly, and the ZnO catalyzing GO reduction opens a new approach to prepare graphene derivates.
本文展示了一种新颖且简单的制备分级氧化锌/还原氧化石墨烯（ZnO/RGO@RGO）复合材料的方法，该方法以少层氧化石墨烯（GO）和金属锌为起始原料，通过原位金属锌还原和催化GO脱氧等联合工艺实现。金属锌能够在室温下于GO水悬浮液中直接还原GO片层，从而获得一种多孔复合前驱体（ZnO/RGO），其中ZnO纳米颗粒锚定在RGO片层上。接着，在ZnO/RGO前驱体上直接包覆另一层RGO保护层，以获得分级ZnO/RGO@RGO复合材料。在此步骤中，ZnO/RGO表面暴露的ZnO纳米颗粒起到催化剂的作用，在温和的水热条件下加速从额外添加的GO水悬浮液中GO的脱氧过程。本工作探究了金属锌与GO水悬浮液的反应机理，并验证了ZnO的催化作用。所制备的ZnO/RGO@RGO复合材料作为锂离子电池的负极表现出稳定的循环性能和良好的倍率性能。制备ZnO/RGO复合材料的方法经济且环保，并且ZnO催化GO还原为制备石墨烯衍生物开辟了一条新途径。
