Photoreduction of Graphene Oxide and Photochemical Synthesis of Graphene–Metal Nanoparticle Hybrids by Ketyl Radicals

Abstract

The photoreduction of graphene oxide (GO) using ketyl radicals is demonstrated for the first time. The use of photochemical reduction through ketyl radicals generated by I-2959 or (1-[4-(2-hydroxyethoxy)phenyl]-2-hydroxy-2-methyl-1-propan-1-one) is interesting because it affords spatial and temporal control of the reduction process. Graphene-metal nanoparticle hybrids of Ag, Au, and Pd were also photochemically fabricated in a one-pot procedure. Comprehensive spectroscopic and imaging techniques were carried out to fully characterize the materials. The nanoparticle hybrids showed promising action for the catalytic degradation of model environmental pollutants, namely, 4-nitrophenol, Rose Bengal, and Methyl Orange. The process described can be extended to polymer nanocomposites that can be photopatterned and could be potentially extended to fabricating plastic electronic devices.

Sub‐10 nm Ag Nanoparticles/Graphene Oxide: Controllable Synthesis, Size‐Dependent and Extremely Ultrahigh Catalytic Activity

“…Based on these XPS results, the atomic ratio between oxygen and carbon (O/C) is semiquantitatively evaluated to be ≈0.47. On the one hand, these observations indicate the presence of numerous oxygen functionalities on the skeleton of our GO nanosheets, providing abundant active sites for the nucleation and growth of AgNPs . On the other hand, accompanied by the TEM (Figures and ) and XRD (Figure A) results, and together with an in‐depth analysis of the high‐resolution Ag 3d XPS spectra of our products (for details, vide infra), these facts further suggest the successful generation of AgNPs/GO composites, wherein AgNPs and GO nanosheets might hybridize via the oxygen‐containing functional groups of the GO nanosheets.…”

“…The deconvolution of its high‐resolution C 1s XPS spectrum (Figure C) yields four peaks at 284.8, 286.8, 287.8, and 289.0 eV. These peaks, which are typical C 1s XPS spectral characteristics of GO, correspond to the nonoxygenated ring carbon (CC), hydroxyl and epoxy carbon (CO), carbonyl carbon (CO), and carboxylate carbon (OCO), respectively . For the as‐manufactured nanostructures, their survey scan spectra (Figure B) and deconvoluted high‐resolution C 1s XPS spectra (Figure C) exhibit nearly the same patterns except that in addition to the C 1s and O 1s peaks, XPS peaks of Ag 3p 1 , Ag 3p 5 , and Ag 3d could also be distinctly detected.…”

“…Among NMNPs/GO, Ag nanoparticles/GO (AgNPs/GO) have gradually become a hot topic of general concern . In addition to the extraordinary electronic/optical properties, the low cost of Ag relative to other noble metals renders AgNPs/GO feasible yet qualified alternatives for diverse advanced materials .…”

“…In addition to the extraordinary electronic/optical properties, the low cost of Ag relative to other noble metals renders AgNPs/GO feasible yet qualified alternatives for diverse advanced materials . Numerous AgNPs/GO‐based materials have thus far been manufactured by various methods, including chemical, electrochemical, sonochemical, or solvothermal reduction; electron beam, gamma ray, microwave, or light irradiation; biosynthesis; etc . These strategies, however, are disadvantaged by the use of toxic chemicals, multistep/long‐time operations, complex GO premodification steps, AgNP presynthesis or bioextract prepurification procedures, high pressure/temperature, rigorous experimental conditions, or bulky setups.…”

“…Taking 4‐NP reduction as an example, the investigation likely sheds new scientific insights into rational design of surface‐based advanced materials. Considering the excellent multifunctionality of and general interest in AgNP‐based materials, as well as the relatively low cost of Ag compared to other noble metals, our AgNPs/GO might not only have great opportunities as high‐performance catalysts but also be expanded to other frontier fields of advanced nanomaterials.…”