Synthesis of CuO and Cu2O nano/microparticles from a single precursor: effect of temperature on CuO/Cu2O formation and morphology dependent nitroarene reduction. Issue 88 (7th September 2016)

• Record Type: Journal Article
• Authors: Vinod Kumar, V.; Dharani, A.; Mariappan, Mariappan; Anthony, Savarimuthu Philip
• Is Part Of: RSC advances. Volume 6:Issue 88(2016)
• Page Start: 85083
• Page End: 85090
• Publication Date: 2016-09-07
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/c6ra16553b
• Languages: English
• ISSNs: 2046-2069

Abstract

Abstract : CuO and Cu2 O micro/nanoparticles have been synthesized from same precursor in hydrothermal method by controlling temperature and morphology dependent nitroarenes reduction was studied with CuO nano/microparticles. Abstract : CuO and Cu2 O nano/microparticles with pure phases have been synthesized from the same precursor by a hydrothermal method. Hydrothermal heating of Cu(OAc)2 produced CuO at 125 °C whereas pure Cu2 O was obtained at 175 °C. Heating at 150 °C gave a CuO/Cu2 O mixture. In contrast, Cu(acac)2 produced only Cu2 O at all three temperatures. The pure phases of Cu2 O and CuO nano/microparticles were confirmed by PXRD and XPS characterization. The mechanistic studies indicate that decomposition of the organic anion/ligand of the Cu-precursor played a key role in the formation of CuO/Cu2 O nano/microparticles from Cu(OAc)2 /Cu(acac)2 . FE-SEM studies revealed the formation of CuO with a microsphere morphology (125 °C) and a micro-cup for Cu2 O at 175 °C. Nanowires and micron-sized elliptical cylinders were observed for Cu2 O synthesized from Cu(acac)2 . However, calcination of Cu(OAc)2, Cu(acac)2 and Cu(NO3 )2 at 500 °C produced crystalline CuO nano/microparticles with various sizes and morphologies. Further, CuO nano/microparticles investigated for industrially important aromatic nitro to amine conversion showed morphology dependent nitro group reduction. Smaller spherical CuO nano/microparticles obtained from Cu(acac)2 exhibited the highest catalytic activity. The reusability studies indicate that CuO nano/microparticles can be used for up to six cycles. Thus we have presented a simple method to synthesize Cu2 O or CuO from the same precursor and demonstrated the morphology dependent catalytic activity of CuO nano/microparticles.