Morphology dependent field emission from In₂O₃ nanostructures

In₂O₃ nanostructures such as aligned nanocolumn arrays, nanowires and nanopyramids were fabricated using a simple physical evaporation technique. Nanocolumn arrays and the nanowires were produced using an Au catalysed vapour-liquid-solid (VLS) technique and the nanopyramid structures were prepared using a non-catalytic approach. Field-emission studies revealed that the morphologies of these In₂O₃ nanoforms have considerable effects on the field-emission properties. Among these nanoforms, nanocolumn arrays have the lowest turn-on voltage and the highest field enhancement factor. The results indicated that the In₂O ₃ nanoforms could be used as cathode materials for the fabrication of devices based on field-emission properties.