Biologically mediated synthesis of CuO nanoparticles using corn COB (Zea mays) ash for photocatalytic hydrogen production

Abstract

This research article reports the green synthesis of copper oxide (CuO) nanoparticles (NPs) using the aqueous extract of corn cob ash from agricultural residue. This agricultural residue was subjected to a calcination for use as a stabilizing agent. As-synthesized NPs were characterized by various methods such as SEM/EDS, FT-IR, XRD and UV–Visible spectroscopy. The results revealed that the corn cob ash extract acts as an excellent stabilizing agent for the formation of CuO NPs. The XRD peaks match the standard X-ray diffraction patterns of CuO, confirming a monoclinic crystal structure. The SEM images revealed that the NPs are agglomerated, porous and with rough edges. Meanwhile, the EDS analysis confirmed the existence of Cu and O elements in NPs synthesized by the green route. The absorbance band is at 350 nm and the band gap is around 1.65 eV. Hydrogen evolution was observed on green synthesized CuO in the photocatalysis measurement.