Ti1.3Nb1.76O7 porous microspheres: a low-niobium niobate for Li+-storage anodes

Niobate Li + -storage anode materials, especially TiNb 2 O 7 (TNO), have garnered significant attention for their intrinsically safe characteristics and substantial capacities as well as fast and stable electrochemical kinetics. However, several limitations hinder the application of TNO in lithium-ion battery anodes, chief among them being its high niobium content. Herein, by adjusting the ratio of Ti and Nb elements in TNO, a novel low-niobium Ti 1.3 Nb 1.76 O 7 (LN-TNO) anode material with a micro-sized porous spherical morphology and oxygen-vacancy proportion of 2.8% has been exploited. The oxygen vacancies provide more active sites for electrochemical reactions, enabling impressive rate capability with a 5 C to 0.1 C capacity retention of 70.4%. LN-TNO demonstrates stable cycling performance with 86.5% capacity retention after 250 cycles at 5 C. Even at − 10 °C, it delivers a super high-rate behavior with 46.7% capacity retention from 5 C to 0.1 C, along with stable cycling performance retaining 90.0% of its capacity upon 500 cycles at 5 C. Owing to the outstanding properties mentioned above, LN-TNO demonstrates promising potential for practical applications in high-performance Li + storage. Graphical abstract The alternative text for this image may have been generated using AI.