Layered Niobium Oxide Hydrate Anode with Excellent Performance for Lithium-Ion Batteries

Benefiting from the advantages of cost-effectiveness and sustainability, lithium-ion batteries (LIBs) are recognized as a next-generation energy technology with great development potential. Herein, niobium oxide hydrate (H₃ONb₃O₈) synthesized by a facile and inexpensive solvothermal method is proposed as the anode of LIBs. It is a layered two-dimensional material composed of negatively charged two-dimensional lamellae and positively charged interlayer hydronium ions. The former consist of NbO₆ octahedral units connected by bridging oxygen. Because of the mutual effect of hydronium ions and niobium oxide quantum dots, niobium oxide hydrate exhibits excellent electrochemical activity when used as an anode material. This compound is first applied to lithium-ion batteries, obtaining a high specific capacity (1232 mAh g^-1) at 100 mA g^-1 and maintaining an outstanding performance after 200 cycles. Therefore, this work not only proposes a simple preparation method of niobium oxide hydrate but also expands the variety of high-performance anode materials.