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

Coating of anatase titania on clinoptilolite by metal organic chemical vapor deposition method: enhanced mesoporosity and photocatalytic activity

Kais Elghniji, Elimame Elaloui, and Younes Moussaoui

University of Gafsa, Gafsa, Tunisia

E-mail: k.elghniji@yahoo.fr

Abstract: Clinoptilolite-supported TiO₂ (TiO₂/CP_MOCVD) has been synthesized by metal organic chemical vapor deposition method (MOCVD). Titanium precursor was evaporated at 110 °C under nitrogen flow rate to promote the surface interaction between titanium species and clinoptilolite. The effect of titanium precursor on the crystalline structure and the surface area of clinoptilolite were investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD), transformed infrared spectroscopy (FT-IR), Raman spectroscopy, and Brunauer–Emmett–Teller measurement. XRD and SEM results indicate that TiO₂ precursor interacted with the support, decreasing the crystallinity of the clinoptilolite. The analysis by FT-IR spectroscopy further confirms that the titanium species were bound to clinoptilolite through Ti–O–Si bonds. The TiO₂/CP_MOCVD catalyst showed a mesoporous structure with the distribution of pores in several dimensions 3.7–7.1 nm, with high specific surface area (~ 471 m²/g). MOCVD improved the adsorption capacity of the catalyst surface towards the pollutants. TiO₂/CP_MOCVD particles turn yellow after adsorption of salicylic acid. The development of the yellow color is a clear indication of the formation of charge transfer titanium (IV) salicylate surface complex. Photocatalytic decomposition of SA in aqueous solution was carried out using TiO₂/CP_MOCVD. Experimental results revealed that TiO₂/CP_MOCVD required shorter irradiation time (120 min) for complete decomposition of SA than commercial P25 Degussa and TiO₂/CP_imp (clinoptilolite-supported TiO₂ using impregnation method). The TiO₂/CP_MOCVD can be recycled at least four times without loss in activity, indicating their magnificent stability.

Keywords: TiO₂ ; Clinoptilolite ; MOCVD ; Mesopores ; Photocatalysis 

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-017-0350-1

Chemical Papers 72 (5) 1159–1168 (2018)