Crystal-seeds induced construction of ZnO-ZnFe₂O₄ micro-cubic composites as excellent anode materials for lithium ion...

This work aims at designing a fine assembly of two different transition metal oxides with a distinct band-gap energy into a bi-component-active hetero-structure to enhance the hetero-interface interactions and synergetic functionalities of bi-components to improve electrochemical performance. Herein, a facile marriage of crystal-seeds induction and hydrothermal reactions has been utilized to fabricate ZnO-ZnFe₂O₄ micro-cubic composites. Benefiting from the synergetic effects of the bi-functional components and their unique hetero-junction structure, the ZnO-ZnFe₂O₄ micro-cubic composites exhibit a significant improvement in lithium storage performance. The reversible capacity is retained at a value of 811 mA h g^-1 after 200 cycles at a current density of 100 mA g^-1. Even at high current densities of 1 and 5 A g^-1, the electrodes are still able to deliver capacities of 584 and 430 mA h g^-1 after 200 cycles, respectively.