CeHIO6·4H2O: A novel, highly efficient catalyst for degrading organic dyes without light illumination at room temperature

Abstract It is still desirable to obtain the catalysts to degrade organic dye pollutants at room temperature, which meets the current demands of pollutant-removing and energy-saving simultaneously. By a facile precipitation method, we prepared in this work a new, highly efficient CeHIO 6 ·4H 2 O catalyst. By characterization, it was found that the CeHIO 6 ·4H 2 O sample is in nature a yellow inorganic semiconductor with particle size of 0.2–10 μm, band gap of 2.75 eV, low surface area of 1.52 m 2  g −1 and amorphous structure. The CeHIO 6 ·4H 2 O catalyst showed high activity in degradation of rhodamine B (RhB), methyl orange (MO) and methylene blue (MB) in the dark at room temperature. After being used for 3 cycles, it did not undergo significant loss of activity and kept its chemical composition unchanged in the degradation experiments. More importantly, its activity is remarkably higher than that of the previously reported Ce(IO 3 ) 4 , CeGeO 4 , ZrHIO 6 ·4H 2 O and Ce-doped MoO 3 analogues. The major active species and the catalytic mechanism for the dye degradation were proposed.