Hybrid Polymeric Nanostructures Stabilized by Ferric Cations with Photo-Fenton Performance: Implications for Recoverable Multicatalyst Design

Abstract

Iron ions, as traditional high-efficiency Fenton reaction catalysts, react with hydrogen peroxide to generate hydroxyl radicals, thereby degrading organic pollutants in wastewater. However, in aqueous solutions, iron ions have a poor chemical stability and are therefore difficult to recover from the reaction medium. We propose that their complexation with double-hydrophilic block copolymers can lead to the formation of nanocatalysts with improved chemical and colloidal stability. Iron ions were added at different molar ratios to a solution of a double-hydrophilic block copolymer, that is, poly­(ethylene oxide)-block-poly­(acrylic acid) to lead to the formation of colloidal structures. Spontaneous formation of highly monodisperse micelles with a hydrodynamic diameter around 25 nm occurs when the charge ratio between the positive iron ions and the negative PAA polyanions is close to one. By combining several techniques, a precise description of the core–shell architecture was achieved. These structures are chemically stable in the pH range of 3–7 and have been successfully used as photo-Fenton catalysts through the degradation of naphthol blue black. Compared to the traditional homogeneous Fenton reaction, these colloidal structures have improved chemical and colloidal stabilities as well as a higher recyclability.

Customizing Cerium Oxide Particle Synthesis with Hybrid Polyion Complex Templates for Enhanced Oxidation Performance in Photo‐Fenton Processes

“…The viability of the CeO 2 /Fe 2 O 3 structure as a catalyst for the photo‐Fenton reaction was systematically investigated employing methylene blue (MB) as a model pollutant. The initiation of the Fenton experiment occurred under irradiation upon combining methylene blue, catalyst, and H 2 O 2 [8b] . The UV‐visible spectrum, depicted in Figure 3a shows the structure of methylene blue (Figure 3a inset) and the evolution of UV‐visible spectrum as a function of time during photo‐Fenton process.…”

Double-hydrophilic block copolymer–metal ion associations: Structures, properties and applications

“…Recently, experiments were p. 21 reported on iron(III) HPIC, which catalyzed a photoFenton reaction with better recyclability than simple iron ions. [88] The catalytic properties of metal HPICs in which metal ions were used to form inorganic nanoparticles have also been reported in the case of a Au HPIC (for the catalytic reduction of nitroarene) [86] and Cd HPIC (leading to photocatalytic H2 production). [58] As seen in Figure 10, the Cd HPIC made of PiPrOX-b-PAGA copolymer led to CdS nanoparticles producing hydrogen much more efficiently than free CdS nanoparticles.…”

“…References Aluminum [44][45][46][47][48][49][50] Barium [51][52][53][54][55][56] Cadmium [56][57][58][59] Calcium [49, 51-53, 55, 60-69] Cobalt [54,56,70,71] Copper [45,49,[70][71][72][73] Dysprosium [74] Europium [75][76][77][78][79] Gadolinium [51,75,[77][78][79][80]180] Gallium [81] Gold [14,[82][83][84][85][86] Iron [87,88,152] Lanthanum …”

Simple hybrid polymeric nanostructures encapsulating macro-cyclic Gd/Eu based complexes: luminescence properties and application as MRI contrast agent

“…Well-defined HPICs were formed with a hydrodynamic radius around 10 nm similarly to the size obtained for HPICs based on Cu 2+ , Fe 3+ , Ga 3+ or Gd 3+ with a similar block copolymer (Table 2). 18,[39][40][41] The number of lanthanide and zirconyl ions within one Ln 3+ / Zr@HPIC can be roughly estimated from previous studies on Gd@HPICs and Ga@HPICs based on the same polymer and is a around 1000 thousand ions (i.e. 50 ions lanthanide per nano-objects).…”