Tunable Synthesis of Hematite Structures with Nanoscale Subunits for the Heterogeneous Photo-Fenton Degradation of Azo Dyes

Abstract

Facile syntheses of branched hematite (α-Fe2O3) crystals with fine-tuning of their nanoscale subunit morphologies were reported. Starting from Prussian red and bisolvent systems with controlled temperature as the crucial parameters, fine-tuning of the nanoscale subunit morphologies in the context of controlling the anisotropic growth of branched α-Fe2O3 crystals was demonstrated. The systematic and optimized studies significantly improved the controlled synthesis of the hierarchical growth of nanoscale subunits, leading to the formation of branched dendritic leaflike (secD3D, tertD2D, and tertD3D) and hyperbranched (secS2D and hypB2D) α-Fe2O3 particles for their size-reduced variants used in photocatalysis. The kinetics of the photo-Fenton degradation of three azo dyes (chlorazol black, direct blue, and methyl orange) with five types of branched dendritic α-Fe2O3 particles were compared systematically.

Anisotropic α-Fe2O3/AgAu/Polydopamine Nanostructures for Photothermally Enhanced Antibacterial Applications

“…All of them possess the typical absorption peaks located at 567 and 483 cm −1 , which are attributed to the classic Fe−O stretching absorption. 43 In comparison to α-Fe 2 O 3 , the reduced intensity of Fe−O absorption is attributed to the decreasing weight ratio. The PDA absorption can be hardly observed, and this result is due to the thin nature of the PDA shell.…”

“…Figure d shows the FTIR spectra of the α-Fe 2 O 3 , α-Fe 2 O 3 /Ag 0.7 Au 0.8 /PDA, and α-Fe 2 O 3 /Ag 1.7 Au 0.8 /PDA nanospindles. All of them possess the typical absorption peaks located at 567 and 483 cm –1 , which are attributed to the classic Fe–O stretching absorption . In comparison to α-Fe 2 O 3 , the reduced intensity of Fe–O absorption is attributed to the decreasing weight ratio.…”

Molecular Nanotechnology for Tomorrow’s World: A Forum Dedicated to Professor Sir Fraser Stoddart on the Occasion of His 80th Birthday

“…11 In another work, Leung et al realized a tunable synthesis of hematite-based structures applied for the efficient photo-Fenton degradation of azo dyes. 12 In addition to the targeted applications, a rationally designed preparation and a fundamental understanding of functional nanosystems are critical to this research field. For example, Wu et al enabled chirality-dependent packing of triangular macrocycles in single crystals, 13 and Smaldone et al developed a useful stereolithography to achieve 3D printing of aramid nanofiber composites with enhanced tensile strength and toughness.…”

“…Trabolsi and coauthors conducted pore surface engineering to achieve isostructural covalent organic framework nanoparticles, exhibiting remarkable oil removal performances (>500 wt %) for various types of oils . In another work, Leung et al realized a tunable synthesis of hematite-based structures applied for the efficient photo-Fenton degradation of azo dyes …”