Preparation of Large-Scale CoS2 Nanowires and Their Raman Study

Structurally sound self-growing large-scale CoS2 nanowires were synthesized via a template-free and catalyst thermal sulfurization process on Co films. After annealing cobalt thin films in pure sulfur (S) vapor produced large area of CoS2 nanowires, we observe symmetrical and vertically alligned nanowires on the thin film surface. After running the thermal treatment in static S atmosphere, the cobalt thin film is converted into polycrystalline CoS2 nanowires and CoS2 film. We recorded the form of the CoS2 nanowires after the cobalt thin film was annealed. We also investigated the influence of the film annealing time and temperature. Aligned and long nanowires can be effectively formed at a temperature of around 400 °C for 5-10 h. The diameter of the CoS2 nanowires is around 10 nm with a length of ~ 2 µm. In addition, the Raman spectra of isolated CoS2 nanowired were lso studied.