SnO2 nanosheets grown on in-situ formed N-doped branched TiO2/C nanofibers as binder-free anodes for sodium-ion storage

SnO2 is considered as a promising anode material for sodium-ion storage. However, the low electrical conductivity and large volume expansion during repeated cycling process hinder its practical application. To address these issues, we designed a hybrid structure in which SnO2 nanosheets were grown on in-situ formed N-doped branched TiO2/C nanofibers (NBT/[email protected]2 NFs). This unique design can improve the conductivity and structural stability of the electrode, provide enough space for volume expansion, and accelerate the transfer rate of electrons and ions, thereby enhancing the electrochemical performance. As a result, when directly used as an anode for sodium-ions batteries, the binder-free NBT/[email protected]2 NFs electrode exhibits outstanding cycling stability, with a reversible discharge capacity of 420.7 mA h g−1 after 500 cycles at 200 mA g−1 and still achieves 330.6 mA h g − 1 at a very high current density of 2000 mA g−1. This work provides a novel strategy for the design of electrode materials for other high-performance battery systems.