Khaki-coloured niobium oxide nanochains with enhanced lithium storage performances

Khaki-coloured niobium oxides (H-Nb2O5) nanochains were synthesised via a facile low temperature solution-based method combined with hydrogenation treatment process. The nano-sized chain-like architectures facilitate the fast lithium ion diffusions. Meanwhile, the hydrogen reduction process can effectively endow Nb2O5 with partial Nb4+ species and/or oxygen vacancies, resulting in a large enhancement of its intrinsic electronic conductivity. When evaluated for lithium storage capacity, the H-Nb2O5 showed twice the rate capability at 20 C compared to that of the pristine Nb2O5 nanochains due to the combination of the reduced path and Nb4+ doping induced high electronic conductivity. This facile hydrogenation method is promising for designing high performance carbon-free electrode materials for lithium ion batteries.