초록 |
Metal oxide/carbon composites have been widely used as energy storage materials, as metal oxides have high capacity and the carbon acts as a conducting matrix for electron transfer. Out of these materials, niobium oxide (Nb2O5)/carbon composites have been preferred due to its high capacity, good cyclability, and stable operation. Herein, we have oxidized a two-dimensional metal carbide (MXene) in CO2 flow gas to fabricate Nb2O5/carbon@Niobium Carbide MXene via one step oxidation. Such a core-shell configuration would explore the high conductivity of core MXene, the fast rate response of shell Nb2O5 and electron “bridge” effect of disordered carbon. The Nb2O5/carbon@ Nb4C3Tx showed 208 mAh g-1 and 141 mAh cm-3 at 50 mA g-1 (0.25 C), and retained 94% of initial specific capacity after 400 cycles with good rate capability. Since oxidized MXene as a Li-ion battery anode has just started to be investigated, there is great room to push the boundaries further and achieve better performances. |