title: Fine CuO anisotropic nanoparticles supported on mesoporous SBA-15 for selective hydrogenation of nitroaromatics.
abstract: SBA-15 modified with APTMS (3-aminopropyl trimethoxysilane) having pore diameter (∼8 nm) has been synthesized and impregnated with 1-10 wt.% Cu using Cu(NO3)2 as a metal source followed by calcination at 350 °C. As-prepared CuO/ap-SBA-15 powder showed changes in the color from white for bare SBA-15 to light green due to formation of anisotropic CuO nanoparticles that exhibited a characteristic plasmon absorption band at 359 and 747 nm. TEM studies showed a change in the morphology of CuO NPs as a function of increased Cu loading. Moreover, well dispersed CuO nanospheres (∼5-6 nm) and nanorods (aspect ratio ∼11-20 nm) having monoclinic crystal phase were observed within the mesoporous channels of SBA-15. Elemental mapping studies confirmed uniform distribution of CuO nanoparticles on the surface of SBA-15. An increase in surface area was also observed from 694 m(2) g(-1) for SBA-15 to 762 m(2) g(-1) for 10 wt.% Cu loading probably due to the deposition of excess of CuO nanoparticles on the outer siliceous surface. The catalytic activity also increased with Cu loading and 10 wt.% CuO/ap-SBA-15 catalyst displayed the highest catalytic activity for the reduction of m-chloronitrobenzene and m-nitrotoluene with 83% and 100% selectivity for m-chloroaniline and m-aminotoluene respectively.
authors.affiliation: School of Chemistry and Biochemistry, Thapar University, Patiala 147004, Punjab, India.
authors.forename: Shweta
authors.initials: S
authors.lastname: Sareen
authors.affiliation: Department of Chemistry, Maharishi Markandeshwar University, Mullana 133207, Haryana, India.
authors.forename: Vishal
authors.initials: V
authors.lastname: Mutreja
authors.affiliation: School of Chemistry and Biochemistry, Thapar University, Patiala 147004, Punjab, India.
authors.forename: Satnam
authors.initials: S
authors.lastname: Singh
authors.affiliation: School of Chemistry and Biochemistry, Thapar University, Patiala 147004, Punjab, India. Electronic address: bpal@thapar.edu.
authors.forename: Bonamali
authors.initials: B
authors.lastname: Pal
keywords: Anisotropic CuO nanoparticles; CuO nanostructures; CuO/SBA-15 nanocomposites; Heterogeneous catalysis; Host–guest systems; Mesoporous SBA-15; Post modification; Selective nitroaromatic reduction; Supported catalyst; Zeolite analogues