Membrane MnO2 coated Fe3O4/CNTs negative material for efficient full-pseudocapacitance supercapacitor

Abstract In this work, carbon nanotubes (CNTs) decorated with Fe3O4 nanoparticles and then covered with MnO2 membrane were synthesized by hydrothermal method as supercapacitor negative material. Thanks to this special structure, the Fe3O4/CNTs@MnO2 negative material showed a high specific capacitance of 643.8 F g−1 at 1 A g−1. Moreover, the full-pseudocapacitance symmetrical supercapacitor device was assembled, exhibiting excellent specific capacitance (132 F g−1 at 1 A g−1) and wonderful stability (63% at 1 A g−1 after 10,000 cycling). It is worth mentioned that the stability wasn’t decayed from 1000 to 10,000 cycling. Specially, after lighting one white LED bulb (working voltage greater than 3 V), two fully charged symmetric supercapacitors (in series) can continue to light four red LED bulbs.