Intercalating Organic Hybrid Cadmium Antimony Sulfide Nanoparticles into Graphene Oxide Nanosheets for Electrochemical Lithium Storage

Inorganic metal sulfides have received extensive investigation as anode materials in lithium-ion batteries (LIBs). However, applications of crystalline organic hybrid metal sulfides as anode materials in LIBs are quite rare. In addition, combining the nanoparticles of crystalline organic hybrid metal sulfides with conductive materials is expected to enhance the electrochemical lithium storage performance. Nevertheless, due to the difficulty of harvesting the nanoparticles of crystalline organic hybrid metal sulfides, this approach has never been tried to date. Herein, nanoparticles of a crystalline organic hybrid cadmium antimony sulfide (1,4-DABH₂)Cd₂Sb₂S₆ (DCAS) were prepared by a top-down method, including the procedures of solvothermal synthesis, ball milling, and ultrasonic pulverization. Thereafter, the nanoparticles of DCAS with sizes of ∼500 nm were intercalated into graphene oxide nanosheets through a freeze-drying treatment and a DCAS@GO composite was obtained. Compared with the reported Sb₂S₃- and CdS-based composites, the DCAS@GO composite exhibited superior electrochemical Li⁺ ion storage performance, including a high capacity of 1075.6 mAh g^-1 at 100 mA g^-1 and exceptional rate tolerances (646.8 mAh g^-1 at 5000 mA g^-1). In addition, DCAS@GO can provide a high capacity of 705.6 mAh g^-1 after 500 cycles at 1000 mA g^-1. Our research offers a viable approach for preparing the nanoparticles of crystalline organic hybrid metal sulfides and proves that intercalating organic hybrid metal sulfide nanoparticles into GO nanosheets can efficiently boost the electrochemical Li⁺ ion storage performance.