Fe3O4/carbon hybrid nanoparticle electrodes for high-capacity electrochemical capacitors.
Fe3O4/carbon hybrid nanoparticles (FeCHNPs) were fabricated using dual-nozzle electrospraying, vapor deposition polymerization (VDP), and carbonization. FeOOH nanoneedles decorated with polypyrrole (PPy) nanoparticles (FePNPs) were fabricated by electrospraying pristine PPy mixed with FeCl3 solution, followed by heating stirring reaction. A PPy coating was then formed on the FeOOH nanoneedles through a VDP process. FeCHNPs were produced through carbonization of PPy and FeOOH phase transitions. These hybrid carbon nanoparticles (NPs) were used to build electrodes of electrochemical capacitors. The specific capacitance of the FeCHNPs was 455 F g(-1), which is larger than that of pristine PPy NPs (105 F g(-1)) or other hybrid PPy NPs. Furthermore, the FeCHNP-based capacitors exhibited better cycle stability during charge-discharge cycling than other hybrid NP capacitors. This is because the carbon layer on the Fe3 O4 surface formed a protective coating, preventing damage to the electrode materials during the charge-discharge processes. This fabrication technique is an effective approach for forming stable carbon/metal oxide nanostructures for energy storage applications.
School of Chemical and Biological Engineering, College of Engineering, Seoul National University, 599 Gwanangno, Gwanakgu, Seoul, 151-742 (Korea), Fax: (+82) 2-888-1604.
Jun Seop
JS
Lee
Dong Hoon
DH
Shin
Jaemoon
J
Jun
Choonghyeon
C
Lee
Jyongsik
J
Jang
D002244:Carbon / Q000737:chemistry*; D025802:Electric Capacitance; D011211:Electric Power Supplies; D004566:Electrodes; D052203:Ferrosoferric Oxide / Q000737:chemistry*; D053758:Nanoparticles / Q000737:chemistry*
D002244:Carbon; D052203:Ferrosoferric Oxide
capacitors; carbon; electrospray; nanoparticles; polypyrrole