TiNb 2 O 7 materials were synthesized via a microwave-assisted microemulsion technique and a conventional solid-state reaction route. Microwave-assisted microemulsion process produced TiNb 2 O 7 powders with small particle sizes (50-100 nm) and increased surface area (22.4 m 2 /g) in comparison to the samples synthesized from solid-state method. Micelles in the microemulsion acted as nano-reactors and confined the grain growth of TiNb 2 O 7 . The microwaveassisted microemulsion-derived TiNb 2 O 7 powders presented a high discharge capacity of 333.2 mAh/g at 0.1C. The materials also delivered 94.8% retention at 5C after 100 cycles. The solid-state derived samples only processed the 283.2-mAh/g discharge capacity at 0.1C with 83.2% retention at 5C after 100 cycles. The amended capacity and cyclability of microwave-assisted microemulsionderived TiNb 2 O 7 resulted from the augmented Li + diffusion and the diminished charge transfer resistance. It was also found that the microwave-assisted microemulsion-derived TiNb 2 O 7 delivered 208 mAh/g discharge capacity at 10C, which was higher than solid-state derived samples (92 mAh/g). The improved capacity was owing to the enhancement in pseudocapacitive contribution.Present research indicated that the microwave-assisted microemulsion method effectively enhanced the electrochemical performance of TiNb 2 O 7 powders.

SnO 2 -coated TiNb 2 O 7 powders were synthesized via the solution coating method in the present research. The SnO 2 layers with a thickness of 3-5 nm were homogeneously coated on the surface of TiNb 2 O 7 particles. TiNb 2 O 7 coated with SnO 2 of 5 mol% with high Li + diffusion coefficient delivered the discharge capacity of 319.5 mAh/g, which was 6.6% higher than that of the non-coated samples. The enhancement of capacity for the coated TiNb 2 O 7 was owing to the low chargetransfer resistance of 17.5 Ω in contrary to the non-coated TiNb 2 O 7 (27.8 Ω).SnO 2 -coated TiNb 2 O 7 possessed an improved capacity retention of 85.2% at 5 C after 100 cycles, superior to the non-coated TiNb 2 O 7 (79.8%). On the other hand, the excessive amounts of SnO 2 coating led to the reduction in the capacity of the prepared samples. The excessive amounts of SnO 2 layers suppressed the Li + diffusion and increased the charge-transfer resistance. The obtained results in this study indicated that coating of TiNb 2 O 7 with appropriate amounts of SnO 2 significantly improved the electrochemical performance of TiNb 2 O 7 .