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Geopolymer (GP) spheres made from coal fly ash (FA) and rice hull ash (RHA) waste products are utilized as both support matrix and dopant applied to titania (TiO₂) photocatalyst for organic dye degradation in wastewater. Processing of FA and RHA via suspension-solidification method resulted in GP spheres with nanoporous morphology. The nanocrevices enabled low-energy sol-gel TiO₂ coating technique because they served as anchoring sites on the geopolymer surface that favored rigidity and larger surface area. The GP-TiO₂ system has been characterized by infrared spectroscopy, X-ray diffraction and scanning electron microscopy coupled with energy dispersive X-ray spectroscopy. Diffuse reflectance spectroscopy revealed a narrowing of the GP-TiO₂ system optical band gap due to the interaction of metal dopants contained in RHA and FA with TiO₂, thus making the GP-TiO₂ system a visible-light-active photocatalyst, as confirmed by methylene blue dye degradation measured through UV-Vis spectroscopy.