Nanocrystalline Titania Coated Metakaolin and Rice Hull Ash Based Geopolymer Spheres for Photocatalytic Degradation of Dyes in Wastewater

Geopolymer spheres made from metakaolin and rice hull ash have exceptional chemical and mechanical stability, making them promising catalyst support matrix for photoactive compounds. In this paper, titania was deposited on geopolymer sphere via horizontal vapor phase growth method, which produced nanotitania crystals embedded on the surface. The titania-coated geopolymer spheres resulted in 90% dye photodegradation activity that can be used repeatedly, thus qualifying the products as sustainable materials for wastewater treatment.