Heterojunction Cr2O3-Ag2O nanocomposite decorated porous polymer monoliths a new class of visible light fast responsive heterogeneous photocatalysts for pollutant clean-up

Abstract

We report a unique Cr2O3-Ag2O nanocomposite that is homogeneously dispersed on a polymer monolith by solvothermal assisted polymerization method. The surface morphology and structural features of the visible light responsive photocatalyst is characterized using FE-SEM-EDAX, HR-TEM-SAED, p-XRD, XPS, PLS, FT-IR, UV-Vis-DRS, TGA, BET/BJH and PEC measurements. The characterization data reveals a voluminous macro-/meso-porous monolithic framework with superior surface properties that promotes photocatalytic activity through the uniformly dispersed Cr2O3-Ag2O nanocomposites. Electrochemical and spectroscopic studies reveal a lower recombination rate of the photogenerated charges for (60:40) Cr2O3-Ag2O nanocomposite, with an energy band gap of 2.35 eV. A comprehensive analysis of physicochemical parameters such as solution pH, catalyst quantity, dopant stoichiometry, dye concentration, electron acceptors, illumination time and intensity reveals superior photocatalytic efficacy in dissipating organic dye (Reactive Brown-10) pollutants, within 1 h of visible light (300 W/cm2) irradiation. The high surface area of the Cr2O3-Ag2O dispersed polymer monolith facilitates effectual dissipation of massive organic pollutants using a nominal photocatalyst quantity (100 mg), in the optimized pH range of 3.0–4.0. The monolithic photocatalyst ensures easy transport of pollutants to the photoactive sites, thereby ensuring ≥ 99% dye degradation, through superoxide anion radical species. The proposed photocatalyst is environmentally benign with excellent durability and reusability.