Computational Screening and Experimental Validation of Promising Wadsley-Roth Niobates

The demand for efficient, high-capacity energy storage has driven research into the development of advanced materials for lithium-ion batteries, among which Wadsley–Roth (WR) niobates stand out due to rapid Li+ diffusion within ReO3-like blocks (n × m × ∞) and good electronic conductivity along shear planes. Despite the remarkable features of WR phases, there are presently less than 30 known compounds which limits identification of structure–property relationships for improved performance as well as the identification of phases with more earth-abundant elements. In this work, we have dramatically expanded the set of potentially (meta)-stable compositions (with ΔHd < 22 meV/atom) to 1301 (out of 3283) through high-throughput screening with density functional theory (DFT). This large space of compounds was generated through single- and double-site substitution into 10 known WR-niobate prototypes using 48 elements across the periodic table. To confirm the structure predictions, we successfully synthesized MoWNb24O66 and validated it with X-ray diffraction. The measured lithium diffusivity in MoWNb24O66 has a peak value of 1.0 × 10–16 m2/s at 1.45 V vs Li/Li+ and achieved 225 ± 1 mAh/g at 5C. Thus, a computationally predicted phase was realized experimentally with performance exceeding Nb16W5O55 (a recently reported WR phase benchmark material). Overall, the computational data set of potentially stable compounds with one realized that has competitive performance provide a valuable guide for experimentalists toward discovering long-duration battery materials.