Fabrication of single phase p-CuInSe₂ nanowire arrays by electrodeposited into anodic alumina templates

Single-phase CuInSe₂ nanowire (NW) arrays were prepared at various pH values in a heated electrolyte by using pulse electrodeposition techniques and an anodized aluminum oxide template. X-ray diffraction showed that the CuInSe₂ NW nucleation mechanism received H⁺ constraints when the NWs were deposited at pH 1.7 with a (112) orientation and annealed at 550 �C. The CuInSe₂ NW band gap was determined to be approximately 1 eV through optical measurements. Transmission electron microscopy showed that at the pH value of 1.7, small particles of the single-phase CuInSe₂ NWs aligned along the crystallographic direction are nucleated to form large particles. Scanning electron microscopy revealed that the NW diameter and the length were 80 nm and 2.3 μm, respectively. From Mott-Schottky and Ohmic contact plots, the CuInSe₂ NWs were found to be p-type semiconductors, and their work function was estimated to be approximately 4.69 eV.