Revisiting Rb2TiNb6O18 as electrode materials for energy storage devices

In the search of new materials for future generation Li-ion batteries, a look into past has brought multicationic oxide Rb2TiNb6O18 to foreground. Structural characterization this material been carried out thanks combination XRD, SEM and HRTEM highlighting complex structure material. Ion exchange was performed in order replace rubidium ions by hydrated protons. Then, comparative study obtained proton exchanged analogues H2TiNb6O18 when used as negative electrode is depicted terms both electrochemical behavior. Interestingly, while only negligible Li+ insertion evidenced phase, exhibits much higher lithium intercalation between 1 V 3 vs Li/Li+. A specific capacity 118 mAh.g−1 reported cycled at 0.02 A.g−1. solid solution type mechanism revealed situ XRD experiments. Moreover, during lithiation, volume increases 1% showing interest phase develop “zero-strain” materials.