Nickel oxide decorated halloysite nanotubes as sulfur Host materials for lithium–sulfur batteries

Abstract

Lithium–sulfur batteries with high energy density still confront manychallenges, such as polysulfide dissolution, the large volume change of sulfur,and fast capacity fading in long-term cycling. Herein, a naturally abundantclay material, halloysite, is introduced as a sulfur host material in the cathodeof Li–S batteries. Nickel oxide nanoparticles are embedded into the halloysitenanotubes (NiO@Halloysite) by hydrothermal and calcination treatment toimprove the affinity of halloysite nanotubes to polysulfides. TheNiO@Halloysite composite loaded with sulfur (S/NiO@Halloysite) isemployed as the cathode of Li–S batteries, which combines the physicalconfinements of tubular halloysite particles and good chemical adsorptionability of NiO. The S/NiO@Halloysite electrode exhibits a high dischargecapacity of 1205.47 mAh g−1at 0.1 C. In addition, it demonstrates enhancedcycling stability, retaining≈60% of initial capacity after 450 cycles at 0.5 C.The synthesized NiO@Halloysite can provide a promising prospect andvaluable insight into applying natural clay materials in Li–S batteries