Understanding the high-performance Fe(OH)₃@GO nanoarchitecture as effective sulfur hosts for the high capacity of lithium-sulfur batteries

Although the lithium-sulfur battery has received widespread attention for its promising future in the energy-storage practical application areas, it still faces some obstacles that hinder commercial and practical utilizations. Here, a Fe(OH)₃@GO nanocomposite, 10–20 nm particles anchored on GO surface, as a novel sulfur host has been developed for Li-S batteries, where the construction of Fe(OH)₃@GO nanoarchitecture proceeds via electrostatic self-assembly process between the negatively charged GO sheets and the positively charged Fe(OH)₃ colloid particles. The wealthy hydroxyl groups of Fe(OH)₃ would appeal to intermediate polysulfides more strongly than Fe₂O₃, resulting in the surface chemical bonds between Fe(OH)₃ and polysulfides. On the other hand, GO often contains different functional groups capable of entrapping polysulfides via forming chemical interactions. These advantages of both Fe(OH)₃ and GO give the S/Fe(OH)₃@GO cathode high specific capacity (1569.8 mA h g⁻¹ at 0.5 C), good rate performance up to 5 C, and long cycling stability over 500 cycles under high sulfur loading. Compared to Fe₂O₃@GO nanocomposites, the enhanced electrochemical performance for the Fe(OH)₃@GO nanocomposite could be attributed to both sufficient surface binding interaction and fast charge-transfer kinetics.