Two - step approach of fabrication of three - dimensional reduced graphene oxide - carbon nanotubes - nickel foams hybrid as a binder - free supercapacitor electrode

- 3D rGO-CNTs-NF electrode is fabricated by combination of EPD and FCCVD.
- EPD with excellent uniformity is an economical processing technique.
- FCCVD is beneficial to obtain more compact and uniform VACNTs.
- The hybrid shows a high specific capacitance of 236.18 F g−1 and a high energy density of 19.24 Wh kg−1.
- This work provides various assumptions for designing hierarchical rGO-based architecture.

A facile method is designed to prepare 3D reduced graphene oxide (rGO) - carbon nanotubes (CNTs) - nickel foams (NF). In this research, the 3D rGO-CNTs-NF electrode is fabricated by combination of electrophoretic deposition and floating catalyst chemical vapor deposition. The vertically-aligned CNTs forests not only effectively prevent stacking of rGO sheets but also facilitate the electron transfer during the charge/discharge process and contribute to the whole capacitance. Moreover, the 3D rGO-CNTs-NF hybrid can be used directly as electrodes of supercapacitor without binder. Additionally, the hybrid shows a specific capacitance of 236.18 F g−1 which is much higher than that of the rGO - NF electrode (100.23 F g−1). Importantly, the energy density and power density of 3D rGO-CNTs-NF are respectively as high as 19.24 Wh kg−1 and 5398 W kg−1, indicating that our work provides a way to design hierarchical rGO-based architecture composed of rGO, CNTs and various electroactive materials for high-performance energy storage devices.

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