Mitigating antisite disorder in layered LiNi0.5Mn0.3Co0.2O2 cathodes via lanthanum–boron co-doping

Cation disorder arising from Li + /Ni 2+ antisite defects remains a fundamental limitation to the structural stability and long-term performance of layered nickel-rich cathodes. Here, we report a rational co-doping strategy employing lanthanum and boron to regulate lattice ordering in layered LiNi 0.5 Mn 0.3 Co 0.2 O 2 through a scalable wet-chemical sol–gel synthesis followed by controlled high-temperature sintering. The introduction of La–B dopants promotes enhanced crystallographic ordering within the layered framework, as evidenced by an increased I 003 /I 104 intensity ratio of 1.4, indicative of suppressed cation mixing and improved Li-layer integrity. Spectroscopic and microstructural analyses confirm the successful incorporation of lanthanum into the transition-metal sublattice, while boron contributes to stabilizing the surface oxygen framework and mitigating interfacial reactivity. Density functional theory calculations further reveal that selective lanthanum substitution induces minimal lattice strain (∼0.11%), thereby stabilizing the layered structure against mechanical degradation and microcrack formation during repeated lithium insertion and extraction. As a result of improved structural coherence and defect suppression, the co-doped cathode exhibits enhanced cycling durability, retaining over 91% of its initial capacity after extended cycling at moderate rates. This study demonstrates that synergistic La–B co-doping effectively suppresses antisite defects, stabilizes lattice oxygen, and improves the durability of layered oxide cathodes.