Excellent air storage stability of Na-based transition metal oxide cathodes benefiting from enhanced Na−O binding energy

•Constructing a weak orbital hybridization between transition metal and oxygen significantly improve the air stability of O3-layered oxide cathode materials.•A stronger binding energy between bulk sodium and host lattice mitigates the spontaneous active Na loss and the irreversible structure transformation upon air exposure.•Air stability is closely associated to the crystal stacking parameter of dO-Tm-O/dO-Na-O.