Boosting stability and dendrite-free Zn anode achieved by four-in-one functional protection layer in zinc ion batteries

Key Words:METAL; INTERFACE; EVOLUTION
Abstract:The uneven Zn2+ deposition-induced dendrite growth and water-induced corrosion reactions have become major obstacles for high-performance Zn-ion batteries (ZIBs). To tackle these issues, a zeolitic structured ZIF-8 layer with hydrophobicity, zincophilicity and super-high electrical double-layer capacity is in situ integrated onto the Zn plate. Unlike other MOFs-based layers, the Zn (002) facet exposure accompanied by the formation of ZIF-8 can be achieved to regulate the Zn deposition direction. Experimental and theoretical results demonstrate that this "four-in-one" ZIF-8 layer effectively suppresses Zn anode corrosion and H2 evolution, accelerates ion transfer kinetics and promotes uniform Zn2+ deposition and oriented crystal growth along the Zn (101) plane. This stabilizes the electrode/electrolyte interface with inhibited side reactions and dendrite-free anode. Therefore, ZIF-8@Zn symmetric cells reveal a stable cycle life of 2080 h at 10 mA cm-2 and 5 mAh cm- 2, while ZIF-8@Zn// V-EG full cells demonstrate an excellent capacity retention of 92.4 % at 1 A g- 1 after 1150 cycles. This work highlights the significance of the "four-in-one" ZIF-8 protection layer in stabilizing Zn anodes for highperformance ZIBs.
Volume:518
Issue:
Translation or Not:no