Enhanced photocatalytic degradation of methyl orange by gamma Bi_2O_3 and its kinetics

摘要

Bismuth oxide (Bi_2O_3) is prepared in its pure body centered cubic form (γ) without surfactant at a calcination temperature of 500 °C and its photocatalytic degradation property is studied using methyl orange as the model pollutant. γ-Bi_2O_3 degrades 95.2% of methyl orange in 90 min and the kinetics of degradation is studied using pseudo first and second order. The obtained results are found to be best fit in pseudo second order equation which predicts that the adsorption is controlled by more than one step and it is verified from the Weber-Morris equation.