Au@TiO2/reduced graphene oxide nanocomposites for lithium-ion capacitors

To meet the overwhelming demands of next-generation energy storage devices, efforts to develop advanced electrode materials with excellent specific capacity/capacitance and cyclic durability are underway. In this study, we develop hierarchical ternary composites based on Au@TiO2 core-shell nanoparticles anchored onto reduced graphene oxide nanosheets through a one-pot hydrothermal method. These composites can be utilized as anodes for electrochemical lithium storage. The ternary composite anodes deliver a high specific capacity of 905 mAh g(-1) at 100 mA g(-1) after 100 cycles, accompanied by good rate capability. Hybrid lithium-ion capacitors with Au@TiO2/reduced graphene oxide anodes and activated carbon cathodes show a maximum energy density of 110 Wh kg(-1) and power density of 11 kW kg(-1), along with excellent capacitance retention of 83%, even after 1000 cycles. This suggests that our composites have potential as electrode materials for high-performance supercapacitors.