First-principles study of positron interface states in graphene-stacked LiCoO2 Cathodes

Carbon nanostructures play a crucial role in improving the performance of rechargeable Li-ion batteries by forming LiCoO2/C interfaces. In this work, we employ two-component density functional theory calculations to investigate the electronic properties of these interfaces. Our study demonstrates that positrons confined at the interface serve as effective probes of buried interfaces in the cathodes. We further reveal that different Li-termination can affect the positron interface states. Moreover, positron annihilation calculations show significant overlap with both LiCoO2 and carbon orbitals, and the momentum distribution indicates a clearly shift toward the low-momentum region, primarily driven by the contributions from O-2p and C-2p orbitals. These findings establish a theoretical framework for future positron experiments, supporting the development of advanced energy materials for batteries and catalysis.