Silicon-protected, vertically grown MoS2 nanosheets for high-performance thin-film Li-ion batteries.

Silicon-coated molybdenum sulfide nanosheets were prepared in a thin-film shape (Si–MoS 2 TFs) through metal organic chemical vapor deposition (MOCVD) and radio frequency (RF) sputtering. By using MOCVD, the MoS 2 thin films composed of nanosheets were vertically grown on stainless steel substrates. To address the problem of polysulfide dissolution and shuttling effect of MoS 2 during discharge and charge reactions in thin-film Li-ion batteries, the entire surfaces of MoS 2 TFs were covered with silicon layers using RF sputtering. Compared with pristine MoS 2 TFs without protection, the Si–MoS 2 TFs showed excellent reversibility with a high capacity of ∼2000 mAh g−1 for 500 cycles in thin-film Li-ion batteries. Both materials – MoS 2 and Si – were synergistically taken into account to enhance the ability to store Li ions in the host structures and complement each other during repeated conversion and alloying reactions. The underlying reaction principle was elucidated, which provides insight into developing MoS 2 -based thin-film cathodes. [ABSTRACT FROM AUTHOR]