Improving field emission properties of CuO nanowires by coating with ZnO nanoparticles

A facile solution route of self-assembled zinc oxide (ZnO) nanoparticles (NPs) on the surface of cupric oxide (CuO) nanowires (NWs) was presented, and field emission arrays with ZnO NPs-CuO NWs hybrid emitters were fabricated. The NW based conjugation by coating ZnO NPs on CuO NWs was confirmed by transmission electron microscopy (TEM) image. The turn on electric fields of the ZnO NPs-CuO NWs hybrid emitters decreased to 2.37 V mu m(-1) compared with 4.95 V mu m(-1) of pure CuO NWs, and the field enhancement factor was significantly enhanced from similar to 869 (pure CuO NWs) to similar to 1678 (ZnO NPs-CuO NWs). The ZnO-CuO NWs hybrid emitters also have higher emitting uniformity, which indicated the efficient field emission properties for the hybrid emitters.