Copper and conjugated carbonyls of metal–organic polymers as dual redox centers for Na storage

A flower-like π–d conjugated MOP (Cu-TABQ) was prepared using tetramino-benzoquinone (TABQ) as an organic ligand and Cu 2+ as a transition metal node. It shows dual redox centers of Cu 2+ /Cu + and CO/C–O with high reversible capacity for sodium-ion batteries.