Comparison of Photo-Catalytic Efficiency of Various Metal Oxide Photo-Catalysts for the Degradation of Methyl Orange

The present study explores the effectiveness of various photocatalytic materials for the degradation of methyl orange (MO) in aqueous solution as model compound. The catalysts which are tested include commercial ZnO, nano ZnO, TiO₂, nano TiO₂ and titanium silicalite-1 (TS-1). Preliminary studies were performed to optimize the reaction parameters such as photocatalytic degradability of MO, pH, amount of photocatalyst and initial concentration of the dye solution. The optimum catalyst weight, pH of the dye solution and initial dye concentration were 1.5 g/L, 10 and 400 μM, respectively. Comparison of photocatalytic activity of different semiconducting materials has clearly indicated that nano ZnO (commercial) is the most active photocatalyst in the degradation of methyl orange.