Biosynthesis of monodispersed stable copper nanoparticles using Syzygium cumini: characterization and potential applications

This study reports a novel, facile and eco-friendly approach for the reduction of CuSO₄·5H₂ O into stable and well-dispersed copper nanoparticles (Cu NPs) using aqueous leaf extract of Syzygium cum-ini. The reduction was affirmed by UV-Visible spectrophotometer maximum absorbance at 535 nm. The effect of various parameters including temperature, pH, precursor salt concentration and incu-bation time on particle size of Cu NPs has been evaluated. Fourier-transform infrared spectroscopy showed a strong band at 3,307 cm^–1 indicating the O–H groups of alcohols and phenols. Scanning electron microscopy analysis showed spherical morphology of Cu NPs with particle size of 19 nm. The prepared nanoparticles showed excellent catalytic performance for the removal of methylene blue (MB) from the aqueous medium using sodium borohydride (NaBH₄) as a reducing agent. The kinetic studies showed that Cu NPs followed pseudo-first-order for catalytic reduction of MB.