Sulfur-doped ZnFe 2 O 4 nanoparticles with enhanced lithium storage capabilities

Abstract

Sulfur-doped ZnFe₂O₄ nanoparticles were synthesized through sulfurizing ZnFe₂O₄ nanoparticles in the hydrothermal process using Na₂S as the sulfur source. The content of sulfur dopant was tuned from 0.70 to 1.26 wt% by controlling concentrations of Na₂S solutions. When evaluated as anode materials for lithium-ion batteries, sulfur-doped ZnFe₂O₄ nanoparticles exhibited much higher reversible capacities, better rate performances, and more excellent cycling stabilities than the pristine ZnFe₂O₄ nanoparticles. After 60 cycles at a current density of 100 mA g⁻¹, the electrode of sulfur-doped ZnFe₂O₄ nanoparticles (1.26 wt%) delivered a reversible specific capacity of 604 mA h g⁻¹, while the pristine ZnFe₂O₄ electrode only remained 200 mA h g⁻¹.