GaSb nanocomposite: New high-performance anode material for Na- and K-ion batteries

As representative next-generation secondary battery systems, sodium-ion batteries (SIBs) and potassium-ion batteries (PIBs) are key candidates to achieve zero-carbon emission. Herein, we introduce a versatile GaSb nanocomposite anode for SIBs and PIBs. The performance and phase transition mechanism for GaSb, pure Ga, and Sb with Na and K ions are evaluated. Furthermore, three-step nanoconfinement and stabilization of GaSb crystallites are achieved in the GaSb nanocomposite. The nanostructure of the GaSb nanocomposite, consisting of approximately 2–4 nm GaSb crystallites uniformly distributed in an amorphous carbon matrix, promotes the electrochemical reaction kinetics with Na and K ions, and the chemical and mechanical stabilities of the GaSb nanocomposite electrodes. The GaSb nanocomposite anode possesses highly reversible initial volumetric and gravimetric capacities and superior high-rate capabilities. In this study, we offer new insights into the phase transition mechanisms of GaSb with Na and K ions and promising performance GaSb nanocomposite anodes for SIBs and PIBs.