ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Sol-gel synthesis, characterisation, and photocatalytic activity of porous spinel Co₃O₄ nanosheets

Manoj Pudukudy and Zahira Yaakob

Fuel Cell Institute, The National University of Malaysia, UKM, 43600, Bangi Selangor, Malaysia

E-mail: zahirayaakob65@gmail.com

Abstract: Mesoporous spinel Co₃O₄ nanosheets were synthesised via a simple sol-gel route using the Pluronic P123 triblock copolymer as the stabilising agent. Their structural, morphological, and textural properties were characterised. FTIR spectrum revealed the formation of cobalt oxide without any surface adsorbed impurities. Face centered cubic phase of spinel Co₃O₄ with the mean crystalline size of 26 nm was assigned by the X-ray diffraction analysis without the formation of other phases. Porous nanosheets and cave-like morphologies were identified from the scanning electron microscopy (SEM) images. Highly agglomerated more or less spherical particles with well separated lattice fringes, representing the oriented growth of nanocrystals, were noticed on the transmission electron microscopy photographs. Surface area analysis revealed that the spinel has high surface area of about 25 m² g⁻¹ with monomodal mesoporosity. The average pore size distribution was found to be about 15.8 nm. The as-prepared spinel photocatalyst showed a mild photocatalytic activity in the degradation of methylene blue (2.5 mg L⁻¹) under UV light irradiation with air as the oxidising agent. Photocatalytic activity of the as-prepared reusable Co₃O₄ was found to be higher than that of the commercial spinel powder.

Keywords: spinel Co3O4 – porous nanosheets – sol-gel synthesis – photodegradation – reusability

Full paper is available at www.springerlink.com.

DOI: 10.2478/s11696-014-0561-7

Chemical Papers 68 (8) 1087–1096 (2014)