Two-dimensional TiNCl for capacitive-like lithium-ion storage

Abstract

In this study, TiNCl was designed and applied in high-rate lithium-ion batteries (LIBs), and the mechanism of the energy storage in TiNCl was uncovered. The Ti-N layer serves as the electronic conductive unit for its high conductivity, while the polyhedral channels constructed with Cl facilitate the transmission of Li ions serving as the ionic conductive units. In addition, due to the negatively charged nature of Cl, the TiNCl anode has a capacitive contribution up to 99.5% at 1 mV s −1 . Even at a high rate of 50 C, it still retains a remarkable reversible capacity of 202 mA h g −1 after 1000 cycles. The concept based on the structure design develops new electrode materials with desired properties.