Magnetic-porous microspheres with synergistic catalytic activity of small-sized gold nanoparticles and titania matrix


HAMALOĞLU K. Ö. , Sag E., Kip C. , ŞENLİK E. , Kaya B. S. , Tuncel A.

FRONTIERS OF CHEMICAL SCIENCE AND ENGINEERING, cilt.13, sa.3, ss.574-585, 2019 (SCI İndekslerine Giren Dergi) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 13 Konu: 3
  • Basım Tarihi: 2019
  • Doi Numarası: 10.1007/s11705-019-1799-y
  • Dergi Adı: FRONTIERS OF CHEMICAL SCIENCE AND ENGINEERING
  • Sayfa Sayıları: ss.574-585

Özet

Fe3O4 nanoparticles immobilized on porous titania in micron-size range were decorated with small-sized gold nanoparticles and used as a plasmonic catalyst for the reduction of 4-nitrophenol. Monodisperse-porous magnetic titania microspheres were synthesized with bimodal pore-size distribution by the sol-gel templating method. Small-sized gold nanoparticles obtained by the Martin method were attached onto the aminated form of the magnetic titania microspheres. A significant enhancement in the catalytic activity was observed using the gold nanoparticle-decorated magnetic titania microspheres compared to gold nanoparticle-decorated magnetic silica microspheres because of the synergistic effect between small-sized gold nanoparticles and titania. The synergistic effect for gold nanoparticle-attached magnetic titania microspheres could be explained by surface plasmon resonance-induced transfer of hot electrons from gold nanoparticles to the conduction band of titania. Using the proposed catalyst, 4-nitrophenol could be converted to 4-aminophenol in an aqueous solution within 0.5 min. The 4-nitrophenol reduction rates were 2.5-79.3 times higher than those obtained with similar plasmonic catalysts. The selection of micron-size, magnetic, and porous titania microspheres as a support material for the immobilization of small-sized gold nanoparticles provided a recoverable plasmonic catalyst with high reduction ability.