Preparation And Study On Photocatalytic Degradation Activity Of Fe³⁺-modified Titania/Graphene Oxide Hybrid Materials

With the progress of the manufacture and technologies, water treatments havedrawn more and more attention because of the growing "water pollution" problem.Photo-catalysts, based on semiconductors, are able to decompose the organicpollutants into non-toxic matters under solar light, which is of great significance forenvironment protection. Among the existing photo-catalysts, titania is one of the mostpotential candidates because of its unique properties, such as low price, non-toxicity,and stability upon irradiation. However, titania using as catalyst has some intrinsicdrawbacks, such as low utilization efficiency of solar energy, low quantum efficiency,easy aggregation and low lipophilicity. In this work, to overcome these disadvantages,Fe3+and grapheme oxide were used to improve photocatalytic activity of titania.Fe3+, the atomic radius of which is similar to that of Ti4+, has half filled electronconfiguration (3d5). Fe-T was synthesized by adsorbing and depositing Fe3+on thesurface of P25through vigorous agitation. Graphene is a one-atom-plied flake ofsp2-bonded carbon atoms in a hexagonal two-dimensional lattice, and its electrontransfer rate may be up to15000cm2V1sat room temperature. GO-Fe-T wasobtained by compositing Fe-T with graphene oxide through vigorous agitation insolution. Using methylene blue (MB) as substrate, the photocatalytic degradationactivity of Fe-T and GO-Fe-T were tested. According to photocatalytic degradationefficiency, the optimum weight ratio of Fe3+to P25is2wt%, and the degradation rateis34.9%in1.5h, which is slightly higher than that of titania. In GO-Fe-T theoptimum weight ratio of GO to Fe-T is10wt%. GO can improve the light absorptionability and the dye adsorption ability of Fe-T, and photo-catalytic activity of10wt%GO-2wt%Fe-T was2times than that of2wt%Fe-T.β-diketone complexes, Iron acetylacetonate(Fe(acac)3), was used to modify thesurface of titanium dioxide. Fe(acac)3-T and GO-Fe(acac)3-T were synthesizedaccording to the method above. Using methylene blue (MB) as substrate, thephotocatalytic degradation activity of Fe(acac)3-T and GO-Fe(acac)3-T were tested. According to photocatalytic degradation efficiency, the optimum weight ratio ofFe(acac)3to P25is0.25wt%and the optimum weight ratio of GO to Fe(acac)3-T is10wt%. Photo catalytic activity of0.25wt%Fe(acac)3-T was1.5times than that oftitania, and photo catalytic activity of10wt%GO-0.25wt%Fe(acac)3-T was1.4times than that of0.25wt%Fe(acac)3-T.