Two-dimensional (2D)
reduced graphene oxide (rGO) is often combined with metal oxides for
energy-storage applications, owing to its unique properties. Here, we show that
amorphous carbon sources, such as organic molecules, can be more efficient in
controlling the size of small metal oxide particles and in achieving uniform
carbon-oxide contacts, which benefits the energy-storage performance. A
composite made of Nb<sub>2</sub>O<sub>5</sub> and amorphous carbon (using
1,3,5-triphenylbenzene as carbon source) outperforms the Nb<sub>2</sub>O<sub>5</sub>-rGO
counterpart as high rate anode electrode material in Li-ion and Na-ion
half-cells and hybrid supercapacitors, delivering specific capacities of 134
mAh g<sup>-1</sup> at 25C against 98 mAh g<sup>-1</sup> for the rGO-based
composite (in Li electrolyte) and 125 mAh g<sup>-1</sup> at 20C against 98 mAh
g<sup>-1</sup> (in Na electrolyte). These findings suggest that amorphous
carbon sources and the development of amorphous carbon-based composites for
Li-ion and Na-ion energy-storage devices are worthy of more attention and
research efforts than those currently given compared to 2D rGO-based
composites.
Amorphous Carbon Against Reduced Graphene Oxide in Li- and Na-Ion Electrochemical Storage Devices: The Case of Nb2O5
