Structural, spectroscopic and biological investigation of copper oxides nanoparticles with various capping agents

• We obtained copper oxide nanoparticles in a powder form.
• Several capping agents were tested.
• Structural and chemical tests showed that the main component were Cu2O and CuO.
• The size of nanoparticles was in the range 7–21 nm.
• Nanoparticles with glycerin and ammonia capping agent showed good antibacterial properties.

Powder composed of copper oxides nanoparticles with various capping agents has been synthesized and characterized with the use of X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and X-ray diffraction (XRD). Polyvinyl alcohol (PVA), glycol propylene, glycerin and glycerin plus ammonia were used as capping agents. The scanning electron microscopy (SEM) studies showed that nanoparticles form agglomerates with the size from 80 to 120 nm while particles size determined from the XRD experiment was in the range from 7 to 21 nm. XPS and XRD experiments revealed that depending on capping and reducing agents used in the synthesis nanoparticles are composed of Cu2O, CuO or a mixture of them. The biological activity test performed for a selected sample where the capping agent was glycerin plus ammonia has shown promising killing/inhibiting behavior, very effective especially for Gram negatives bacteria.