Coating of sulfur particles with manganese oxide nanowires as a cathode material in lithium–sulfur batteries

• Sulfur surface modification by coating with α-MnO2 nanowires was performed.
• Recrystallization of sulfur by heat treatment leads to homogeneous α-MnO2 coating.
• Electrochemically lithiated α-MnO2 improves the rate capability of sulfur cathodes.
• α-MnO2-coated sulfur electrode exhibits enhanced performance in Li–S batteries.

α-MnO2 nanowires were synthesized by a hydrothermal method and then mixed with agglomerated sulfur powders. Homogeneous α-MnO2-coated sulfur particles were obtained by utilizing heat treatment intended to melt and recrystallize the sulfur. α-MnO2 nanowires lead to the suppression in re-agglomeration of sulfur powders during heat treatment and result in successful coating as well as decreased size in parent sulfur powders. The α-MnO2-coated sulfur particles were used as the cathode material for lithium-ion battery applications. Electrochemical evaluation such as the rate capability characteristics and impedance study indicates that the α-MnO2 coated sulfur cathode shows lower resistance and improved rate capability compared to a pristine sulfur cathode.