Zeolitic imidazolate framework-67 derivative/TiO₂ composite coating as an integrated anode for lithium-ion batteries

In this study, Cu-supported ZIF-67 derivative/TiO₂ composite coating was synthesized to increase the conductivity and capacity of TiO₂ and apply the ZIF-67 derivative with excellent electrochemical performance to the integrated anode for lithium-ion batteries (LIBs). The hydrolysis of tetrabutyl titanate in air will produce TiO₂; while the sintering of ZIF-67 in an inert atmosphere will form CoO/C composite. The Cu-supported ZIF-67 derivative/TiO₂ composite coating can be directly employed as an integrated anode for LIBs. It delivers a capacity of 649 mAh g^-1 after 500 cycles at a high current density of 1000 mA g^-1. Even at a high current density of 2000 mA g^-1, it still maintains a capacity of 445 mAh g^-1. The good electrochemical performance of the Cu-supported ZIF-67 derivative/TiO₂ composite coating is mainly attributed to the good conductivity and excellent electrochemical properties of ZIF-67, the inhibition of TiO₂ on reduction of CoO, and the steric hindrance effect of TiO₂ on ZIF-67 particles. (author)