Colloidal Antimony Sulfide Nanoparticles as a High-Performance Anode Material for Li-ion and Na-ion Batteries

To maximize the anodic charge storage capacity of Li-ion and Na-ion batteries (LIBs and SIBs, respectively), the conversion-alloying-type Sb₂S₃ anode has attracted considerable interest because of its merits of a high theoretical capacity of 946 mAh g^-1 and a suitable anodic lithiation/delithiation voltage window of 0.1-2 V vs. Li⁺/Li. Recent advances in nanostructuring of the Sb₂S₃ anode provide an effective way of mitigating the challenges of structure conversion and volume expansion upon lithiation/sodiation that severely hinder the Sb₂S₃ cycling stability. In this context, we report uniformly sized colloidal Sb₂S₃ nanoparticles (NPs) as a model Sb₂S₃ anode material for LIBs and SIBs to investigate the effect of the primary particle size on the electrochemical performance of the Sb₂S₃ anode. We found that compared with microcrystalline Sb₂S₃, smaller ca. 20-25 nm and ca. 180-200 nm Sb₂S₃ NPs exhibit enhanced cycling stability as anode materials in both rechargeable LIBs and SIBs. Importantly, for the ca. 20-25 nm Sb₂S₃ NPs, a high initial Li-ion storage capacity of 742 mAh g^-1 was achieved at a current density of 2.4 A g^-1. At least 55% of this capacity was retained after 1200 cycles, which is among the most stable performance Sb₂S₃ anodes for LIBs.