Bio-template synthesis of spirulina/TiO2 composite with enhanced photocatalytic performance

A visible-light photocatalytic, mesoporous, hierarchical spirulina/TiO2 composite with dye-sensitized surface was fabricated through a one-step hydrothermal process. The microstructure, mesoporous characteristics, surface morphology, as well as the visible-light photocatalytic activities are studied. The spirulina/TiO2 had an anatase phase and an enhanced harvesting of visible light. It was found that the spirulina/TiO2 composite exhibited higher specific surface area with narrow distributed mesopores. The photocatalytic activity of spirulina/TiO2 was evaluated by decolorizing methyl orange aqueous solutions under visible light irradiation. As a bio-template, spirulina prevents TiO2 from further aggregating and provides photosynthesis pigments as in situ dye-sensitizing source. The enlarged specific surface area and dye-sensitized surface improved the visible-light photocatalytic activity of spirulina/TiO2.