A mesoporous AlO zincophilic sieve enables ultra-long lifespan of Zn-ion batteries

The Zn dendrite growth and side reactions hinder the practical application of aqueous Zn-ion batteries. Here, a lactic acid-induced mesoporous Al 2 O 3 (LA-MA) zincophilic sieve was constructed on a Zn anode to resolve these issues. The LA-MA layer with abundant mesoporous ion channels of 3.0 nm can regulate the solvation structure from [Zn 2+ (H 2 O) 6 ]SO 4 2− to more highly coordinated [Zn 2+ (H 2 O) 5 OSO 3 2− ] and restrain water-induced side reactions. Furthermore, the electrostatic attraction with zincophilic groups (C&z.dbd;O, C-O) in the LA-MA layer has a positive effect on reducing the Zn 2+ desolvation barrier and accelerating the Zn 2+ diffusion. Under the synergism, the LA-MA@Zn symmetric cell exhibits over 5100 h at 0.25 mA cm −2 . Impressively, an excellent capacity retention of 94.2% is achieved after 3500 cycles for the CNT/MnO 2 cathode. A mesoporous Al 2 O 3 zincophilic sieve of 3.0 nm pore size and zincophilic groups can regulate the solvation structure and accelerate Zn 2+ diffusion.