Recyclable Fe3O4@SiO2-Ag magnetic nanospheres for the rapid decolorizing of dye pollutants

Abstract

A simple electroless plating method using non-toxic, cost-effective precursors to fabricate Fe3O4@SiO2-Ag nanospheres for catalytic reduction of dye pollutants is developed. Incorporating the individual advantages of Ag and Fe3O4 nanoparticles, the Fe3O4@SiO2-Ag nanospheres exhibit enhanced catalytic reduction efficiency for rhodamine B and eosin Y compared with those of pure Ag or Fe3O4 nanoparticles, and can also be rapidly separated from aqueous solution using a magnet. The catalytic reaction rate is strongly dependent on both reaction temperature and Fe3O4@SiO2-Ag dosage. The presence of surfactants and inorganic salt (Na2SO4) influences the catalytic activity of the Fe3O4@SiO2-Ag nanospheres. Fe3O4@SiO2-Ag nanospheres show great promise for the treatment of industrial dye pollutants.

Synthesis and stabilization of metal nanocatalysts for reduction reactions – a review

“…95 Therefore, these results corroborate that ligands and surfactants can poison or deactivate the metal catalyst as a consequence of interacting with the catalyst or strongly packing around it, thus adversely affecting the accessibility of catalysant/substrate molecules to the catalyst surfaces. 96 In addition to using organic surfactants or ligands to impede the aggregation of metal NPs, much effort has been devoted to dispersing and immobilizing the metal nanocatalysts onto various carrier systems, such as Kapok bers, 46 chitosan-graed poly(acrylic acid) (PAA) hydrogels, 48 ferrocenyl-based honeycomb oligomer lms, 55 PAA-amidodiol hydrogels, 58 tree-like brushes, 97 core-shell microgels, 98,99 spherical polyelectrolyte brushes, 70 tree-like brushes entrapped in PVA composite hydrogels, 100 PVA hydrogels, 101 polyamidoamine dendrimers 102 and polyelectrolyte/dendrimer multilayer lms. 103 In most of the cases studied, the carrier systems only provide a suitable support for the metal NPs to protect them from aggregation and to facilitate catalyst recycling, 104 without making an additional contribution to the catalytic performance of the resulting composite catalyst, e.g., to enhance the electron mobility.…”

Eco-friendly seeded Fe3O4-Ag nanocrystals: a new type of highly efficient and low cost catalyst for methylene blue reduction

“…It is noticed that the M s value linearly decreases with the increase of the addition quantity of the silver seed colloids or the decrease of the addition quantity of the Fe 3 O 4 nanocrystals. The decrease of M s value may be attributed to the increase of the mass owing to the adherence of silver seeds on the surfaces of the Fe 3 O 4 nanocrystals 53 or the interaction between Fe 3 O 4 nanocrystals and silver seeds. 54 Even if M s value decreases to 59.1 emu g −1 for the Fe 3 O 4 -Ag 10 mg-150 mL and 63.6 emu g −1 for Fe 3 O 4 -Ag 10 mg-30 mL, the samples still have the strong magnetic responsivity and can be magnetically separated easily from aqueous solution by imparting an external magnetic field, which renders them economic and reusable for various applications.…”

Determination of Band Alignment in the Synergistic Catalyst of Electronic Structure-Modified Graphitic Carbon Nitride-Integrated Ceria Quantum-Dot Heterojunctions for Rapid Degradation of Organic Pollutants

“…Thermodynamically, the reduction of dyes using NaBH 4 is favorable but kinetically restricted in the absence of a catalyst. This results in great potential difference between the donor and acceptor molecules. , The reduction of dyes through a catalytic process is considered an electron transfer from the donor (NaBH 4 ) to the acceptor (RhB) via the catalyst (g-C 3 N 4 /CeO 2 QDs) surface. Therefore, the higher electron-transfer rate of the catalyst greatly improves the efficiency of the reduction reaction.…”