In situ growth of gold nanoparticles on magnetic γ-Fe2O3@cellulose nanocomposites: a highly active and recyclable catalyst for reduction of 4-nitrophenol

Abstract

In this study, a facile synthetic method has been developed for in situ growth of Au nanoparticles (NPs) on magnetic g-Fe 2 O 3 @carboxylated cellulose nanospheres using 2,2,6,6-tetramethylpiperidinyl-1-oxyl radical (TEMPO) oxide cellulose as linkage and reducing agent. The size of the as-prepared Au NPs can be tuned from 14 to 38 nm by the initial concentration of the gold salt used in the reaction mixture. Only one step was needed to synthesize the magnetic g-Fe 2 O 3 @cellulose nanospheres. The formed g-Fe 2 O 3 @carboxylated cellulose@Au is highly dispersible in aqueous solution and its potential as a magnetic catalyst is proved by the reduction reaction of 4-nitrophenol to 4-aminophenol. In particular, there was no visible decrease in the catalytic activity of the reused catalysts even after being recycled five times, which is preferred in terms of cost and environmental protection. Due to the absence of any other reducing agent during the proposed process, both the synthesis steps and the reaction cost were remarkably decreased, which makes it very suitable for industrial-scale production of recyclable catalysts.

Biofunctionalized MnFe2O4@Au core–shell nanoparticles for pH-responsive drug delivery and hyperthermal agent for cancer therapy

“…Interestingly, the spectrum does not show any detectable Cl signal which usually within the bonding energy ranges from 196 to 204 eV. Thus it proves that there is a complete reduction of Au (III) to Au (0) onto Mf which is very well confirmed from TEM analysis [43][44][45][46]. The O1s peak (531.9 eV) can be seen which corresponds to the surface component oxygen atoms.…”

Gold-supported magnetically recyclable nanocatalysts: a sustainable solution for the reduction of 4-nitrophenol in water

“…The high-resolution Au 4f spectra of both Au-based nanomaterials can be deconvoluted in two components with BEs of 84.2-84.5 and 87.9-88.2 eV which are respectively assigned to Au 4f 7/2 and Au 4f 5/2 bands from metallic gold, conrming the reduction of Au(III) to Au(0) during the in situ immobilization step. 37,38 This is also sustained by the absence of the Au 4f doublet from Au(III) which typically occurs at 86.9 and 90.6 eV (for Au 4f 7/2 and Au 4f 5/2 , respectively), demonstrating that the Au(III) from HAuCl 3 was completely reduced. 38,39 To provide further insights on the chemical design of the magnetic nanosupports, the parent Mn nanoparticles before and aer the coating with the silica shells and functionalization with the organosilanes were characterized by FTIR spectroscopy.…”

“…37,38 This is also sustained by the absence of the Au 4f doublet from Au(III) which typically occurs at 86.9 and 90.6 eV (for Au 4f 7/2 and Au 4f 5/2 , respectively), demonstrating that the Au(III) from HAuCl 3 was completely reduced. 38,39 To provide further insights on the chemical design of the magnetic nanosupports, the parent Mn nanoparticles before and aer the coating with the silica shells and functionalization with the organosilanes were characterized by FTIR spectroscopy. In the FTIR spectrum of the parent Mn sample (Fig.…”

Microwave-assisted rapid synthesis and characterization of CaF 2 particles-filled cellulose nanocomposites in ionic liquid

“…As new environment-friendly materials, cellulose-based nanocomposites were widely used as forest products and engineering materials because of their unique properties such as biodegradation and bio-renewable nature (Eichhorn et al, 2010;Robert, Ashlie, John, John, & Jeff, 2011;Xiong, Wang, Zhang, Lu, & Lan, 2014). Cellulose-based nanocomposites not only can enrich the family of materials, but may also affect the development direction of future materials.…”