Development of low-emission photocatalytic cement composites with co-ground TiO₂–Fly Ash and TiO₂–calcium carbonate systems

Abstract

This study presents an innovative method for producing low-emission cement composites with photocatalytic properties by partially replacing Portland cement with fly ash, ground granulated blast furnace slag, and calcium carbonate. Novel ground systems combining fly ash-TiO₂ or calcium carbonate-TiO₂ were synthesized via high-energy ball milling to enhance dispersion and minimize TiO₂ agglomeration. The modified composites exhibited improved hydration kinetics, including reduced setting times and up to 50% lower cumulative hydration heat. Mechanical tests confirmed comparable or superior compressive and flexural strengths as compared with the reference materials. All TiO₂-containing composites showed UV-induced photocatalytic activity, with anatase-based systems yielding the best results. Carbon footprint analysis confirmed the environmental benefits, particularly in reducing CO₂ emissions. These findingssupport the development of multifunctional, sustainable cementitious materials for eco-efficient construction.