Facile synthesis and characterization of cupric oxide (CuO) nanoparticles: Inexpensive and abundant candidate for light harvesting

Abstract

Cupric Oxide (CuO), is an inexpensive and non-toxic p-type semiconductor material with a monoclinic crystal structure having indirect band gap (Eg) 1.2 eV -1.9 eV. In this study, co-precipitation method has been employed to synthesize CuO nanoparticles. The samples were calcinated at 200°C or 400°C for decomposition of hydroxides to oxide. The XRD pattern of the CuO nanoparticles annealed at 400°C exhibited well defined peaks and are consistent with the standard values showing monoclinic structure of CuO with particle size in the range around 10 nm -12 nm and 14 nm-17 nm for slighty different precursor materials both samples annealed at 200°C. The nanoparticles size got aggregated when they are annealed at 400°C. This may be attributed to the agglomeration of the particles at high temperature. Hereby we are emphasizing the fact that the interest on old semiconductor like copper oxide still remains at a time when many new semiconductors such as the perovskites and organic semiconductors are being studied for PV applications is mainly due to sustainability. Both copper and oxygen are abundant elements like silicon and thus there can be no supply concern in the long run.