Preparation and photocatalytic activity of iron oxide-loaded potassium titanate layered compounds

Iron oxide-loaded hydrous potassium tetratitanate (K0.3Ti4O7.3(OH)1.7) compounds consisting of 1.48 wt% (sample 'B'), 1.87 wt% (sample 'C') and 5.60 wt% (sample 'D') of iron oxide were synthesized by suspending the K0.3Ti4O7.3(OH)1.7 (sample 'A') in Fe2(SO4)3 solution for 24 h, followed by washing several times with deionized water and then dried at 120 degrees C for 24 h. The K0.3Ti4O7.3(OH)1.7 was synthesized by refluxing the K2Ti4O9 x 2H2O in 1 M HNO3 solution. Band-gap energies of the K0.3Ti4O7.3(OH)1.7 and the iron oxide-loaded samples are 3.12 +/- 0.6 eV and 2.23 +/- 0.09 eV, respectively. Photooxidation activity towards methylene blue decomposition under fluorescence irradiation was found to decrease as follow: sample 'B' > sample 'C' > Sample 'A' > sample 'D' > commercial Fe2O3-Blank. The photoactivity under sunlight irradiation was found to decrease as follow: sample 'B' > sample 'A' > Sample 'C' > sample 'D' > commercial Fe2O3-Blank.