Facile Tailoring of Multidimensional Nanostructured Sb for Sodium Storage Applications

Nanoengineering of metal electrodes are of great importance for improving the energy density of alkali-ion batteries, which have been deemed one of most effective tools for addressing the poor cycle stability of metallic anodes. However, the practical application of nanostructured electrodes in batteries is still challenged by a lack of efficient, low-cost, and scalable preparation methods. Herein, we propose a facile chemical dealloying approach to the tunable preparation of multidimensional Sb nanostructures. Depending on dealloying reaction kinetics regulated by different solvents, zero-dimensional Sb nanoparticles (Sb-NP), two-dimensional Sb nanosheets (Sb-NS), and three-dimensional nanoporous Sb are controllably prepared via etching Li-Sb alloys in H₂O, H₂O-EtOH, and EtOH, respectively. Morphological evolution mechanisms of the various Sb nanostructures are analyzed by scanning electron microscopy, transmission electron microscopy, and X-ray diffraction measurements. When applied as anodes for sodium ion batteries (SIBs), the as-prepared Sb-NS electrodes without any chemical modifications exhibit high reversible capacity of 620 mAh g^-1 and retain 90.2% of capacity after 100 cycles at 100 mA g^-1. The excellent Na⁺ storage performance observed is attributable to the two-dimensional nanostructure, which ensures high degrees of Na⁺ accessibility, robust structural integrity, and rapid electrode transport. This facile and tunable approach can broaden ways of developing high performance metal electrodes with designed nanostructures for electrochemical energy storage and conversion applications.