Xie Xiuqiang, Su Dawei, Zhang Jinqiang, Chen Shuangqiang, Mondal Anjon Kumar, Wang Guoxiu
Centre for Clean Energy Technology, School of Chemistry and Forensic Science, University of Technology Sydney, Broadway, Sydney, NSW 2007, Australia.
Nanoscale. 2015 Feb 21;7(7):3164-72. doi: 10.1039/c4nr07054b.
SnO2/nitrogen-doped graphene nanohybrids have been synthesized by an in situ hydrothermal method, during which the formation of SnO2 nanocrystals and nitrogen doping of graphene occur simultaneously. The as-prepared SnO2/nitrogen-doped graphene nanohybrids exhibit enhanced electrochemical performance for sodium-ion batteries compared to SnO2/graphene nanocomposites. A systematic comparison between SnO2/nitrogen-doped graphene nanohybrids and the SnO2/graphene counterpart as anode materials for sodium-ion batteries has been conducted. The comparison is in a reasonable framework, where SnO2/nitrogen-doped graphene nanohybrids and the SnO2/graphene counterpart have the same SnO2 ratio, similar SnO2 crystallinity and particle size, close surface area and pore size. The results clearly manifest that the improved electron transfer efficiency of SnO2/nitrogen-doped graphene due to nitrogen-doping plays a more important role than the increased electro-active sites within graphene network in enhancing the electro-activity of SnO2/nitrogen-doped graphene nanohybrids compared to the SnO2/graphene counterpart. In contrast to the previous reports which often ascribe the enhanced electro-activity of nitrogen-doped graphene based composites to two nitrogen-doping effects (improving the electron transfer efficiency and increasing electro-active sites within graphene networks) in one single declaration, this work is expected to provide more specific information for understanding the effects of nitrogen-doping into graphene on improving the electrochemical performance of graphene based composites.
通过原位水热法合成了SnO2/氮掺杂石墨烯纳米杂化物，在此过程中，SnO2纳米晶体的形成与石墨烯的氮掺杂同时发生。与SnO2/石墨烯纳米复合材料相比，所制备的SnO2/氮掺杂石墨烯纳米杂化物对钠离子电池表现出增强的电化学性能。已对SnO2/氮掺杂石墨烯纳米杂化物与作为钠离子电池负极材料的SnO2/石墨烯对应物进行了系统比较。该比较在合理的框架内进行，其中SnO2/氮掺杂石墨烯纳米杂化物与SnO2/石墨烯对应物具有相同的SnO2比例、相似的SnO2结晶度和粒径、相近的表面积和孔径。结果清楚地表明，与SnO2/石墨烯对应物相比，氮掺杂导致的SnO2/氮掺杂石墨烯电子转移效率的提高，在增强SnO2/氮掺杂石墨烯纳米杂化物的电活性方面，比石墨烯网络内增加的电活性位点起更重要的作用。与以往报告通常将氮掺杂石墨烯基复合材料电活性增强归因于单一声明中的两种氮掺杂效应（提高电子转移效率和增加石墨烯网络内的电活性位点）不同，这项工作有望为理解氮掺杂到石墨烯中对改善石墨烯基复合材料电化学性能的影响提供更具体的信息。
