Structural investigation of niobium-based oxides as anode materials for lithium-ion batteries via XRD and PDF analysis

Exploring high power density technology with safe operation upon fast-charging is of great significance for EVs to improve the autonomy of both passengers and heavy-duty EVs. The present work introduces a new intercalation host for Li ions, and proposes that a new tetragonal niobium molybdenum oxides Nb4MoO13 with a metastable phase can function as a promising fast-charging anode material for LIBs. Nb4MoO13 can deliver a high initial discharge capacity of 306 mAh g-1 associated with a promising initial coulombic efficiency. We found the phase of such metastable material can be modified by tuning the synthesis condition, and the well-crystallized tetragonal Nb14Mo3O44 and monoclinic Nb12MoO33 can be obtained under various synthesis conditions resulting from the loss of molybdenum and the thermodynamic formation energy. We intend to use XRD and PDF analysis to probe the long-range and local differences between the metastable and thermodynamically stable structures.