| In this work, we present our findings regarding the low-temperature, solid-state conversion of Cu2S nanowires to Cu2S/Cu 5FeS4 rod-in-tube structures, Cu2S/ZnS segmented nanowires, and a full conversion of Cu2S nanowires to ZnS nanowires. These conversion reactions occur at temperatures as low as 105 °C, a much lower temperature than those required for reported solid-state reactions. The key feature of the Cu2S nanowires that enables such low conversion temperatures is the high ionic diffusivity of the Cu+ within a stable S sublattice.;The second portion of this work will focus on the oxide-stabilization and utilization of TiSi2 nanonets as a lithium-ion battery anode. This nanostructure, first synthesized in our lab, was previously demonstrated to possess a lithium storage capacity when cycled against a metallic Li electrode. However, with subsequent lithiation and delithiation cycles, the TiSi 2 nanonet structure was found to be unstable. By allowing a thin oxide layer to form on the surface of the nanonet, we were able to improve the capacity retention of the nanonets in a lithium-ion half-cell; 89.8% of the capacity of the oxide-coated TiSi2 was retained after 300 cycles compared to 62.3% of the capacity of as-synthesized TiSi2 nanonets after 300 cycles. The layered structure of C49 TiSi2 exhibited in the nanonets allows for a specific capacity greater than 700 mAh g-1, and the high electrical conductivity of the material in conjunction with the layered structure confer the ability to cycle the anode at rates of up to 6C, i.e., 10 minute charge and discharge cycles, while still maintaining more than 75% of the capacity at 1C, i.e., 1 hour charge and discharge cycles. |
