Photocatalytic Activity of Combustion Synthesized ZrO₂ and ZrO₂–TiO₂ Mixed Oxides

Abstract

Tetragonal ZrO 2, synthesized by solution combustion technique, was found to be photocatalytically active for the degradation of anionic dyes. The compound was characterized by FT-Raman spectroscopy, X-ray photoelectron spectroscopy, FT-infrared spectroscopy, UV–vis spectroscopy, BET surface area analysis, and zero point charge pH measurement. A high concentration of surface hydroxyl groups was observed over the catalyst, as confirmed by XPS and FTIR. The photocatalytic degradation of orange G, amido black, remazol brilliant blue R, and alizarin cyanine green (ACG) was carried out with this material. The effect of pH, inorganic salts, and H 2 O 2 on the activity of the catalyst was also studied, and it was found that the catalyst maintained its activity at a wide range of pH and in the presence of inorganic salts. Having established that ZrO 2 was photocatalytically active, mixed oxide catalysts of TiO 2 –ZrO 2 were also tested for the photocatalytic degradation of ACG, and the 50% ZrO 2 –TiO 2 mixed oxides showed activity that was comparable to the activity of TiO 2 .