Directly Grown Universally Doped Ultrathin Nanocrystalline Carbon Overlayer Sustains Pragmatic Zinc Metal Anodes

Abstract Rechargeable Zn-ion battery has emerged as a promising alternative to Li-ion battery owing to the high safety and environmental benignity. Nevertheless, dendritic formation and side reaction occurred at the anode side greatly handicap its practical advance. Here, we put forward an effective maneuver to sustain practical Zn anode by optimizing the anode/electrolyte interface, which deals with the direct growth of an ultrathin nitrogen and oxygen co-doped carbon (NOC) overlayer over Zn foil via a scalable plasma enhanced chemical vapor deposition. Thus-designed NOC overlayer can guide the stable Zn deposition along Zn (002) because of the favorable adsorption by dopant atoms and cultivation effect of nanocrystalline carbons, thereby inducing a planar Zn texture. Moreover, the abundant heteroatoms help reduce the solvation energy and accelerate the reaction kinetics. As a result, dendrite growth and side reaction are concurrently mitigated. Symmetric cell harvests durable electrochemical cycling (1125 h at 10.0 mA cm− 2/1.0 mAh cm− 2; 136 h at 30.0 mA cm− 2/30.0 mAh cm− 2). Assembled full battery further realizes elongated lifespans under stringent conditions. This strategy marks a new avenue for the in-situ construction of ultrathin protective coating to optimize the Zn deposition electrochemistry toward pragmatic Zn anode.