Effect of adhesive on photocatalytic NOx removal and stability over polymeric carbon nitride coated cement mortars

Abstract

Photocatalytic cementitious materials (PCMs) are a promising material for air purification at ambient conditions. Herein, polymeric carbon nitride (PCN), a material with high chemical and thermal stability that is responsive to visible light, was employed for the fabrication of PCMs with the assistance of two adhesives (i.e., acrylic latex and waterglass). The effect of the adhesives on the photocatalytic removal of nitrogen oxides (NOx) and their stability over the PCN-coated PCMs was studied under various environmental conditions. Experimental results indicated that the waterglass-based PCMs outperformed the acrylic latex-based PCMs in terms of the photocatalytic NOx removal under visible light irradiation and stability in the peeling and washing trials. The relative humidity had beneficial effects on the NOx removal efficiency for the acrylic latex and deleterious effects on the waterglass incorporated PCMs, due to their distinct surface wettability. The ambient temperature, initial nitrogen monoxide (NO) concentration, and light intensity had a positive impact on the NOx removal efficiency for the as-prepared PCMs.