Enhanced field emission properties of the copper sulfide nanowalls with optimized 3-D morphology

The three-dimensional (3-D) copper sulfide nanowalls with sharp edges were successfully prepared by one-step anodization method. An interesting finding was that the morphology and microstructure of 3-D copper sulfide nanowalls can be regulated and optimized by abjusting the anodization time, and the corresponding field emission (FE) characteristics were significantly improved. The value of turn-on field can be dramatically reduced from 11.84 to 2.84 V/μm and the field enhancement factor up to 19899. Besides, the optimal 3-D copper sulfide nanowalls showed a long-term thermal stability and better conductivity. Preliminary researches indicate that as a promising field emitter, the 3-D copper sulfide nanowalls have potential applications in the field of vacuum micro- or nano-electronic devices.