# The Effect of TiO2 on the Electrochemical Performance of Sb2O3 Anodes for Li-Ion Batteries
###### Abstract  
Antimony (Sb) and its composites have been recognized as potentially good anode materials for lithium-ion batteries (LIBs) due to their relatively high theoretical capacity of 660 mAh g\({}^{-1}\) and to their low cost. However, Sb-based anodes suffer from a high-volume change during the lithiation/delithiation process that results in capacity fading and anode degradation after prolonged charge/discharge cycles. To address this issue, Sb2O3/TiO2 nanocomposite electrodes can be synthesized and used as anodes for LIBs with high capacity and good electrochemical stability. In the present work, TiO2@Sb2O3 composites with different (TiO2:Sb2O3) ratios of 0:1, 1:1, 1:4 and 3:1 were synthesized and directly used as anode materials for LIBs. The electrochemical performance of the TiO2/Sb2O3 composite anode with different ratios of TiO2 to Sb2O3 was evaluated by galvanostatic charge/discharge, rate performance and cyclic voltammetry. The 3:1 (TiO2:Sb2O3) composite anode delivered the highest capacity compared to those of the TiO2, SbO3, 1:1 (TiO2:Sb2O3) and 1:4 (TiO2:Sb2O3) electrodes. The TiO2@Sb2O3 composite anode with a 3:1 ratio exhibited a stabilized capacity of 536 mAh g\({}^{-1}\) after 100 cycles at 100 mA g\({}^{-1}\) and showed excellent rate performance, with current densities between 50 and 500 mA g\({}^{-1}\). The improved electrochemical performance was attributed to the synergistic effect of TiO2 (i.e., the coating of Sb2O3 with TiO2) on reducing the volume change of the Sb anode material after prolonged charge/discharge cycles and on maintaining a stable interface between the electrolyte and the composite electrode material. Sb2O3; TiO2; anode; lithium-ion battery; hydrolysis; hydrothermal 2024 202  
desired higher specific capacities compared to graphite [19]. For example, [PERSON] et al. used an electrostatic spray deposition (ESD) to fabricate porous Sn@Carbon composites at 900 \({}^{\circ}\)C, which delivered a discharge capacity of 638 mAh g\({}^{-1}\) after 315 cycles at 25 mA g\({}^{-1}\)[20]. Nonetheless, Sb composite electrodes are highly attractive for use as anodes in LIBs due to their lower volume expansion of 135% than that of Si anodes (300-400%) [21]. Sb-based composite anode materials exhibit a high theoretical capacity of 660 mAh g\({}^{-1}\)[22] and a good thermal stability similar to Sn and Si composites [23]. Novel methods have been used to prepare hollow and nano-sized structures of Sb as anodes for LIBs with improved electrochemical performance [24; 25; 26; 27; 28]. In fact, Sb has been a striking anode material for LIBs since it undergoes a simpler phase transformation compared to crystallogens (Sn, Ge, and Si) when alloying with Li [29]. In addition to metallic Sb and Sb-alloy materials, antimony trioxide (Sb\({}_{2}\)O\({}_{3}\)) has received great attention as a potential anode for LIBs due to its high theoretical specific capacity of 1109 mAh g\({}^{-1}\) and its good structural stability (during and after cycling) compared with binary antimony oxides of Sb\({}_{2}\)O\({}_{4}\) and Sb\({}_{2}\)O\({}_{5}\)[30; 31; 32]. However, the Sb\({}_{2}\)O\({}_{3}\) anode exhibits a high-volume change after prolonged charge/discharge cycles, thus leading to capacity degradation and poor electrochemical performance of the electrode. Many efforts have been made to address this issue using different synthesis methods. For example, [PERSON] et al. successfully synthesized a bundle-shaped Sb\({}_{2}\)O\({}_{3}\) as anode material for LIBs by preparing a Sb-MOF template through thermal annealing, which exhibited a specific capacity of 594.1 mAh g\({}^{-1}\) after 40 cycles at 20 mA g\({}^{-1}\)[33]. [PERSON] et al. synthesized a polymer binder to prepare a CMC-FA@Sb\({}_{2}\)O\({}_{3}\) electrode that delivered a capacity of 611.4 mAh g\({}^{-1}\) after 200 cycles at 200 mA g\({}^{-1}\)[34]. [PERSON] et al., on the other hand, synthesized a mesoporous structure of Sb\({}_{2}\)O\({}_{3}\) and rGO (reduced graphene oxide) via thermal decomposition [32].