Augmented photocatalytic efficiency stemming from porous core-shell structure: A synergistic manifestation of nano-TiO2 and Fe2O3-enriched recycled clay brick aggregates as hosting matrix

Abstract

In this study, a pioneering methodology is delineated, wherein Fe₂O₃-enriched recycled red brick aggregates are harnessed as avant-garde carrier substrates, resulting in a profound enhancement of the intrinsic self-cleansing capabilities of TiO₂. The innate porous core-shell architecture of these recycled aggregates engenders a notable synergistic interaction between nano-TiO₂ and Fe₂O₃, culminating in a marked escalation of photocatalytic efficiency. An exhaustive examination of the degradation proficiency across a spectrum of samples against methyl blue, conducted over a gradient of temporal intervals, has been executed. The findings indicate that the rates of degradation for all samples increase progressively with the prolongation of exposure to UV irradiation. The control group, consisting exclusively of white cement, demonstrated the most diminutive degradation rate, achieving merely a 4 % reduction in methyl blue concentration through UV irradiation alone. Conversely, the nano-TiO2-modified recycled grey brick aggregate (NT-RGBA) and recycled red brick aggregate (NT-RRBA) samples showcased substantially elevated degradation rates, a phenomenon attributable to the incorporation of photocatalytic agents capable of capitalizing on UV energy to expedite the degradation process of methyl blue. The NT-RRBA composite, an amalgamation of the photocatalytic attributes of TiO₂, the synergistic interplay between Fe₂O₃ and TiO₂, and the intricate three-dimensional pore framework of RRBA, manifested the most pronounced degradation rate. To delve deeper into the determinants influencing the efficacy of photocatalytic degradation, a fuzzy inference system has been deployed to construct a mathematical model that scrutinizes the effects of variables such as the initial concentration of pollutants and the flow rate. This quantitative methodology affords to establish a functional relationship that encapsulates the underlying dynamics of the photocatalytic degradation phenomenon. Deploying this functional material, a derivative of construction detritus, paves the way for an innovative strategy of closed-loop resource utilization, marking a significant milestone towards sustainable development within the construction sector.