A Novel Aqueous Route To Fabricate Ultrasmall Monodisperse Lipophilic Cerium Oxide Nanoparticles

Abstract

Ultrasmall monodisperse 2.3 nm CeO2 nanoparticles have been synthesized by simple ammonia precipitation of cerium nitrate in a mixed glycol–water solvent and phase transferred into apolar solvents. Cerium oxide crystal surfaces were passivated with oleic acid (OA) by reflux under ambient pressure conditions. OA molecules were chemisorbed on the ceria nanoparticle surfaces. Preferential growth of the {100} planes has been observed, ascribed to restricted growth of {111} faces due to adsorbed OA. The surfacted CeO2 nanoparticles were dispersed into a stable, colloidal suspension of fine particles in hydrocarbon solvents. The CeO2 nanocrystals were characterized by X-ray diffraction, Fourier transform infrared spectra, and Raman spectral methods. Transmission electron microscopic images and photon scattering studies proved that the colloidal particles in hydrocarbon solvent were indeed monocrystalline with one crystallite per particle, monodispersed with a narrow size distribution.

Cerium oxide nanoparticle: a remarkably versatile rare earth nanomaterial for biological applications

“…Numerous techniques such as hydrothermal, 20 solvothermal, 21,22 aqueous precipitation, 23 reversed micelles, 24 thermal decomposition 25 and flame spray 26 methods have been reported to synthesize CeONP, while maintaining control of its size and properties. The synthesized CeONP can be bare or wrapped with a coating of protective substances that can be hydrophilic 20 or hydrophobic.…”

Antimicrobial potential of green synthesized CeO₂ nanoparticles from <em>Olea europaea</em> leaf extract

“…[1][2][3][4][5] Its various applications such as acting as a catalyst; use in sensor, solid oxide fuel cells, and sunscreen cosmetics; and its O 2 storage capacity, role in CO 2 solar conversion, and antibacterial applications are due to its idiosyncratic ability to alter the oxidation states. [6][7][8][9][10] Ordinarily, CeO 2 NPs are fabricated by physical and chemical methods including hydrothermal, 11 flame spray pyrolysis, 12 thermal decomposition, 13 aqueous precipitation, 14 and coprecipitation technique. 15 In contrast, green synthesis of metallic oxide NPs offers several advantages such as cost-effectiveness, large-scale commercial production, and pharmaceutical applications.…”

One-pot synthesis of ultra-small cerium oxide nanodots exhibiting multi-colored fluorescence

“…On other hand, rare-earth oxide based fluorescent nanoparticles show negligible toxicity and are easily surface functionalized [7]. Surface passivation using hydrophobic moieties facilitates the facile incorporation of fluorescent nanocrystals in polymer matrices as a possible novel strategy for applications like spectral barcoding, monitoring polymeric scaffolds using fluorescent markers [8,9]. Nanosized cerium dioxide (or ceria) is an extensively studied system for a variety of applications.…”

“…Numerous methods such as hydrothermal [18], alcothermal [13], thermal decomposition [19], and aqueous precipitation [8] have previously been adopted for the synthesis of organophilic CeO 2 nanoparticles with good control of size. Among these, hydrothermal and alcothermal methods demand high pressure and/or temperature equipment which invites additional costs, safety measures and processing time.…”