Alkali Adatom-amplified Schottky contact and built-in voltage for stable Zn-metal anodes

Abstract

Development of rechargeable Zn-metal batteries is limited by side reactions, dendrite growth, and low iondiffusion kinetics on Zn-anodes. Herein, alkali-metal adatom-modified amorphous carbon cluster passivation films (CCF-Ms) were formed on Zn-anodes by radiofrequency plasma thermal evaporation and alkali-metal hydroxide treatment. Plasma energy and alkali-metal hydroxide adatoms develop p-type semiconducting property and chemical durability of the carbon film by inducing dangling bonds and O-containing functional groups, to form Schottky contact between CCF-M and Zn metal with significant Schottky barrier (FSB) and built-in voltage (V-bi). CCF-M, Phi(SB), and V-bi effectively enhanced the corrosion resistance, dendrite suppression, and Zn2+-transport kinetics of the Zn-anode, respectively. Specifically, Zn2+ was guided to deposit rapidly and uniformly below CCF-M without dendrites and side reactions during over 5000 and 1302 cycles in symmetric cell at 1.0 and 10 mA cm(-2), respectively, with a capacity retention of similar to 83% after 5000 cycles at 1.0 A g(V21O5)(-1) in Zn vertical bar V2O5 full cell.