Controlled growth and field emission properties of CuS nanowalls

Vertically oriented CuS nanowalls supported on a copper substrate have been synthesized through a facile method involving an inorganic vapour-solid phase reaction. The CuS nanowalls were well connected to form an extended network. The shapes of the CuS nanostructures could be controlled by adjusting the reaction conditions such as the reaction temperature and the flow rate of argon gas. The crystallinity of the nanowalls was investigated by XRD and their morphological features were characterized by FESEM. Both TEM and SAED analyses revealed that the nanowalls are single-crystalline. The field emission properties of the CuS nanowalls were investigated. The turn-on field and current density of the CuS nanowalls are comparable to those of many other semiconductor nanomaterials, which suggests that the CuS nanowalls may have potential applications in the vacuum microelectronics industry.