Nitrogen‐Doped Porous Graphene Coated with Fe₃O₄ Nanoparticles for Advanced Supercapacitor Electrode Material with Improved Electrochemical Performance

Abstract

With the increasing demand for high‐performance energy storage devices, single materials of ordinary structures for electrode materials have become increasingly difficult to meet people's needs. Therefore, composites of inimitable structures have drawn considerable attention. In this work, nitrogen‐doped porous graphene coated with Fe3O4 nanoparticles (NPGF) is prepared by an efficient and green pyrolysis method. Structural and compositional characterizations confirm that the NPGF nanohybrids possess uniformly distributed pore structure and quite pure composition which is free of any impurities. In addition, electrochemical characterization verifies the excellent electrochemical performance, such as high‐specific capacitance (713 F g−1 at 1 A g−1), prominent rate capability (capacitance retention of 77.3% and 67.9% when the current density is increased respectively from 1 to 10 and 20 A g−1), and outstanding cycling stability (capacitance retention of 94.3% after 3000 cycles). Such promising results suggest that the NPGF nanohybrids have great application prospects in future high‐performance supercapacitors.

Annealing-Assisted Dip-Coating Synthesis of Ultrafine Fe3O4 Nanoparticles/Graphene on Carbon Cloth for Flexible Quasi-Solid-State Symmetric Supercapacitors

“…Furthermore, although many excellent works in the field of supercapacitors have been reported, − we have noticed that the material preparation processes and electrode preparation processes in most of the works are separate, which means that after the successful preparation of electrode materials, these obtained electrode materials must be further made into electrodes. From our previous experimental experience, , the electrode manufacturing process in the latter step is extremely tedious and complicated, and it is time consuming than the preparation of electrode materials in many works, which is apparently unfavorable for the industrialization of these works. Also, most of the electrode materials prepared in the literature are in the form of powder; , therefore, in order to assemble them into electrodes for supercapacitors, it is indispensable to add non-electrochemically active binders to them, which might result in less effective mass loading of active materials, reduced electrode conductivity, and lower power density, thus being detrimental to the improvement of their electrochemical performance. , …”