Ultra-thin conformal deposition of CuInS 2 on ZnO nanowires by chemical spray pyrolysis

Abstract

CuInS 2 (CIS) was deposited on ZnO nanowires by a chemical spray pyrolysis (CSP) method, resulting in an ultra-thin, conformal CIS coating on ZnO forming ZnO-CIS core-shell structures. A high-resolution transmission electron microscope and elemental mapping showed the excellent quality of the coating, while Raman spectroscopy revealed the purity of the materials after core-shell formation. A significant enhancement in band-edge emission of ZnO after CIS coating (also lower defect emissions) was observed, which is due to the peculiar band alignment of the ZnO-CIS combination. Further, the electrical behaviour of the single nanowire ZnO-CIS diode was studied, demonstrating the excellent interface between CIS and ZnO. This technique provides tremendous potential for the fabrication of low-cost nano-electronic devices. © 2012 The Royal Society of Chemistry.