In situ topotactic preparation of porous plate-like Li2ZnTi3O8 as the lithium-ion batteries anode for enhancing electrochemical reaction kinetics and Li+ storage

Spinel Li2ZnTi3O8 (LZTO) is widely studied in the field of anode materials for lithium-ion batteries (LIBs) in recent years because of its stable cycling performance, no volume expansion and higher theoretical capacity than that of Li4Ti5O12. In this work, porous plate-like LZTO is synthesized via a simple in situ topological reaction with layered Titanic acid as the precursor. Due to its special morphology, a large amount of pseudocapacitance is introduced for lithium-ion storage in conjunction with the intercalation reaction. This co-storage mode allows more Li+ to be stored, resulting in the plate-like LZTO getting the highest capacity in the LZTO-based anode. It shows a reversible capacity of 338 mAh/g at 0.1 A/g and maintains excellent performance in long cycle tests under high current density (208 mAh/g after 1000 cycles at 1 A/g and 118 mAh/g after 2000 cycles at 5 A/g). In terms of electrochemical reaction kinetics, the two-dimensional plate structure provides a flat path for electron transport and the micropores on its surface provide many fast channels for the Li+ diffusion. Its simple synthesis method and excellent electrochemical properties prove that it has a great potential to become the new generation of anode materials for LIBs.