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

Chitosan-modified TiO₂ as photocatalyst for ethanol reforming under visible light

Ana Cláudia M. Oliveira, Marluce S. Santos, Luma M. S. Brandão, R. M. Navarro Yerga, J. L. G. Fierro, Manuela S. Leite, Eliane B. Cavalcantia, and Renan Tavares Figueiredo

Universidade Tiradentes, Aracaju, Brazil

E-mail: ss.marluce@gmail.com

Abstract: This work reports the reforming of bio-ethanol on chitosan–TiO₂ hybrid photocatalysts at ambient temperature. The influence of chitosan composition on the photocatalytic performance of chitosan–TiO₂ hybrid was studied. The hybrids were characterized by CHN elemental analysis, nitrogen adsorption–desorption isotherms, thermogravimetric analysis, diffuse reflectance spectroscopy, X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The results showed that the preparation variables used for the incorporation of chitosan on TiO₂ promoted changes in the morphology, superficial area, crystal size and porosity of the photocatalyst, affecting the band gap of this semiconductor and consequently the reactivity of the chitosan–TiO₂ hybrids. The catalysts were evaluated for hydrogen production from ethanol under visible light. It was demonstrated that the calcination temperature of 623 K and a chitosan content of 20% were the most appropriate preparation conditions and the resulting product displays a pore size of 1.9 nm, crystal size of 11.3 nm, BET area of 178 m² g⁻¹ and band gap of 2.92 eV. The calcination temperature of 623 K and incorporation of 20% of chitosan obtained the same results in the conversion rate of hydrogen in comparison to the pure TiO₂ P25.

Keywords: Hydrogen; Ethanol; Photocatalysis; TiO₂; Chitosan

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-016-0095-2

Chemical Papers 71 (6) 1129–1141 (2017)