Fe₂O₃/nitrogen-doped graphene hydrogels are synthesized by a simple hydrothermal method using amino acids with different acidities as morphology-assisting and nitrogen-doping agents, simultaneously. The Fe₂O₃ show a mulberry-shape in the Fe₂O₃/NG-Aspartic composite, which presents a three-dimensional, loose porous network with a large specific surface area. The electrostatic and metal coordination-chelation interaction among the amino acid with different net charge, Fe³⁺ and graphene oxide affect the morphology, structure and final electrochemical properties of the Fe₂O₃/NG composites. The Fe₂O₃/NG-Aspartic shows a higher specific capacity, longer cycle stability and better rate capability, in comparison with the Fe₂O₃/NG samples prepared by using basic, neutral and non-nitrogen-doped composites. The Fe₂O₃/NG-Asp electrode provides high energy and power densities. The superior electrochemical performance of the Fe₂O₃/NG-Aspartic composite is ascribed to the battery-type capacity of iron oxide, the active sites introduced by the nitrogen-doping and the excellent proton-transfer due to the three-dimensional porous network structure of the graphene.

通过简单的水热法，同时使用具有不同酸度的氨基酸作为形态学辅助剂和氮掺杂剂，合成了Fe ₂ O ₃ /氮掺杂石墨烯水凝胶。Fe ₂ O ₃在Fe ₂ O ₃ / NG-天冬氨酸复合物中呈桑树状，呈现出具有大比表面积的三维疏松多孔网络。具有不同净电荷的氨基酸，Fe ³⁺和氧化石墨烯之间的静电和金属配位-螯合相互作用影响Fe ₂ O ₃ / NG复合材料的形貌，结构和最终的电化学性能。铁₂与使用碱性，中性和非氮掺杂的复合材料制备的Fe ₂ O ₃ / NG样品相比，O ₃ / NG-天冬氨酸具有更高的比容量，更长的循环稳定性和更好的倍率性能。Fe ₂ O ₃ / NG-Asp电极可提供高能量和功率密度。Fe ₂ O ₃ / NG-天冬氨酸复合物的优异电化学性能归因于氧化铁的电池型容量，氮掺杂引入的活性位点和三维多孔网络带来的优异的质子转移石墨烯的结构。