Porous Zn2Ti3O8@C rods via in situ carbon coating for superior lithium storage capability

In situ carbon-coated Zn2Ti3O8 (Zn2Ti3O8@C) porous 1D rods were constructed by using only the residual ethylene glycol and polyvinylpyrrolidone from the raw materials as carbon source precursors under a nitrogen atmosphere. This modification resulted in the transformation of the irregular morphology of Zn2Ti3O8 observed during air calcination into longer rod-like structures. The carbon coating of the rods effectively reduced charge transfer resistance and enhanced the Li+ diffusion coefficient of Zn2Ti3O8, leading to improved electrochemical performance. Moreover, this morphological transformation induced significant pseudocapacitive behavior, greatly enhancing the rate capability, cycling stability, and reversible capacity of Zn2Ti3O8. Compared to pure Zn2Ti3O8, the Zn2Ti3O8@C composite exhibited the better electrochemical properties with higher lithium/delithium capacities of 488.8 mAh g(-1) (491.3 mAh g(-1)) at 100 mA g(-1) after 180 cycles. These results highlight the effectiveness of the in situ carbon-coating strategy in producing high-performance electrode materials for lithium-ion batteries.