Vertically well-aligned In₂O₃ cone-like nanowire arrays grown on indium substrates

Single-crystalline, cone-like In₂O₃ nanowire (NW) arrays were directly synthesized on the surface of indium grains without any catalyst by using a simple chemical vapor deposition (CVD) method. The indium grains served both as the indium source, which reacted with different oxygen sources, and the substrate for the growth of the cone-like In₂O ₃ NW arrays. The controllable synthesis of the cone-like In ₂O₃ NW arrays with variable densities, sizes, and morphologies were achieved by adjusting the oxygen sources. A possible mechanism was proposed for the formation of the cone-like In₂O₃ NW arrays. The photoluminescence spectrum of the low-density, cone-like In ₂O₃ NW arrays shows emission in a wide range, from the visible (yellow light) into the near infrared region. Cone-like In ₂O₃ nanowire (NW) arrays were synthesized on the surface of indium grains by using a simple chemical vapor deposition method and a possible mechanism was proposed for their formation. The indium grains served both as the indium source and the substrate for the growth of the cone-like In₂O₃ NW arrays. Their emission properties in a wide visible/infrared range indicate their potential applications in optoelectronics and phototherapy.