Evaluation of self-cleaning performance of TiO₂-intermixed and TiO₂-coated cement mortars under natural sunlight

Abstract

Self-cleaning cementitious materials have gained significant attention due to urban environmental pollution. In this study, nano-TiO₂ (NT) was first mixed with cement mortar. Second, NTs were coated on fresh cast mortars and on hardened surfaces. Photocatalytic efficiency was evaluated using Rhodamine B under natural sunlight with three types of cement: white Portland (WPC), ordinary Portland (OPC), and Portland pozzolana cement (PPC). Among them, PPC cement mortars exhibited superior photocatalytic performance compared to WPC and OPC even with lower dosages of NT. The order of photocatalytic efficiency was highest for the hard-coat followed by fresh-coat and then intermix sample. Furthermore, Rietveld analysis for crystal structure refinement was used, and crystallography analysis (VESTA software) confirmed the presence of specific atoms and bonds in the crystal structure of PPC with NT. Microstructural analysis using XRD, SEM, and EDAX revealed underlying structural changes and thus quantified the hydration products.

Keywords:

• Nano TiO₂
• sunlight
• Rhodamine B
• cement mortar
• microstructure
• photocatalysis

Acknowledgement

This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

Author contributions

N. Avinash Reddy: Conceptualization, Methodology, Validation, Investigation, Writing – original draft, Visualization. P. Sri Chandana: Conceptualization, Methodology, Writing – review & editing, Visualization, Supervision.

Disclosure statement

No potential conflict of interest was reported by the author(s).