A nano-TiO2/corn stalk pith carbon sphere composite material with excellent lithium and sodium storage performance

To overcome the performance bottleneck caused by the single-structure optimization of TiO 2 -based anode materials and to explore a new approach for the resource utilization of agricultural waste, this study synthesized nano-TiO 2 particles (TiO 2 -NP) via a co-precipitation and hydrothermal method. Porous carbon spheres (CSHC) were prepared using discarded corn stalk pith as a carbon source through a hydrothermal carbonization and high-temperature calcination coupling process. Subsequently, TiO 2 -NP was in situ grown onto CSHC, forming a nano-TiO 2 /corn stalk pith carbon sphere composite material (TiO 2 -NP/CSHC), thereby achieving the synergistic enhancement of nano-TiO 2 and biomass-derived carbon. This design not only alleviates the agglomeration of TiO 2 but also significantly enhances the electrochemical performance of the composite material via a three-dimensional conductive carbon network. The prepared TiO 2 -NP/CSHC exhibits a high specific surface area of 101.2 m 2  g −1 and a well-developed porous structure, delivering excellent lithium and sodium storage performance as an anode material for lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs). At a current density of 0.2C, after 100 cycles, the discharge specific capacities were maintained at 1182.5 mA h g −1 and 675.3 mA h g −1 , respectively. Through the structural and functional synergy of TiO 2 -NP and CSHC, the composite material simultaneously achieves high capacity, long cycling stability, and fast charge/discharge capability, while also offering environmental sustainability and cost-effectiveness.