Relationship between network topology and negative electrode properties in Wadsley–Roth phase TiNb2O7

Abstract

Wadsley–Roth phase TiNb2O7, with an octahedral network consisting of TiO6 and NbO6, has attracted significant attention as a negative electrode material for lithium-ion batteries in recent years owing to its excellent safety and high discharge capacity. In this work, we investigated the effect of the network structure (intermediate-range structure), which is considered to form Li+ conduction pathways, on the electrode properties of TiNb2O7. To this end, we prepared TiNb2O7 samples with different charge/discharge properties and generated atomic configurations that simultaneously reproduce both total scattering and Bragg profile data. Topological analyses based on persistent homology demonstrated that the network disorder hidden in the average structure (crystal structure) significantly degrades the negative electrode properties. In conclusion, controlling the network topology is considered the key to improving the negative electrode properties of TiNb2O7. In recent years, the need for safer and more efficient rechargeable batteries has grown due to the increasing use of renewable energy. Traditional lithium-ion batteries have safety risks, such as catching fire, especially when charged quickly. Researchers are exploring new materials to improve battery safety and performance. They studied a material called TiNb2O7, which could be a safer alternative for battery electrodes. Researchers prepared TiNb2O7 using different methods and tested its performance in batteries. They used advanced techniques to analyze the material’s structure at the atomic level. This study focused on how the arrangement of atoms affects the battery’s ability to store and release energy. The results showed TiNb2O7 has potential as a battery electrode, offering good capacity and safety. The study concluded that understanding the atomic structure can guide the development of better battery materials. This summary was initially drafted using artificial intelligence, then revised and fact-checked by the author. In this work, we focused on Wadsley–Roth phase TiNb2O7 with an octahedral network as a negative electrode material for lithium-ion batteries and investigated the effect of the network structure, which is considered to form Li+ conduction pathways, on the electrode properties. To this end, we prepared samples with different charge/discharge properties and generated atomic configurations that simultaneously reproduce both total scattering and Bragg profile data. Topological analyses based on persistent homology demonstrated that the network disorder significantly degrades the electrode properties.