Silver nanoparticles on graphene oxide support

Mar 03, 2014
Silver nanoparticles on graphene oxide support
Figure 1: (Left) Transmission electron microscopy image of Ag-rGO nanohybrids. The inset shows the catalytic conversion of 4-nitrophenol to 4-aminophenol. Figure 2 (Right) Absorption spectra of 4-nitrophenol decreases in intensity and its color fades (inset) due to catalytic conversion.

Silver (Ag) has a high catalytic activity towards many organic and inorganic transformations such as NOx reduction and catalytic oxidation of CO to CO2. In practical applications, catalysts like Ag are affixed to a substrate, usually a solid with a high surface area such as alumina or carbon.

To efficiently use Ag as a catalyst, its specific surface area must be maximized by reducing its particle size. Moreover, the development of simple and low-cost synthesis method is highly desired for practical applications.

Now, Tran Viet Thu and colleagues at Toyohashi University of Technology have shown that graphene oxide (GO) sheets can be used as an excellent support for the growth of Ag particles. GO was first prepared from commercial graphite by oxidation and exfoliation in water. Then the Ag-GO hybrids were prepared by a chemical reduction route using GO and silver nitrate as precursors, sodium borohydride as reducing agent, and trisodium citrate as stabilizer.

Transmission electron microscopy imaging showed very small size (3.6±0.6 nm) Ag particles to be decorated on GO sheets, compared with Ag particles synthesized without GO (tens of nm in size). This decrease in means more Ag atoms were present at the surface and a large increase in the specific . As a result, the Ag-GO hybrids were more efficient for the catalytic conversion of 4-nitrophenol (toxic pollutant) into 4-aminophenol, an intermediate for the production of several drugs. In addition, the Ag-GO hybrids exhibited improved compared to Ag particles synthesized without GO.

The research suggests a low-cost route for the synthesis of catalytic Ag-GO hybrids and highlights the promising use of GO as a support for other functional nanostructures.

Explore further: Improved low-temperature performance of catalytic converters

More information: Tran Viet Thu, Pil Ju Ko, Nguyen Huu Huy Phuc, and Adarsh Sandhu." Room-temperature synthesis and enhanced catalytic performance of silver-reduced graphene oxide nanohybrids."Journal of Nanoparticle Research 15 (10), 1-13 (2013). (DOI): 10.1007/s11051-013-1975-9.

add to favorites email to friend print save as pdf

Related Stories

A novel nanobio catalyst for biofuels

Aug 31, 2012

(Phys.org)—Nanoparticles synthesized from noble metals such as ruthenium, rhodium, palladium, silver (Ag), osmium, iridium, platinum, and gold (Au) are attracting increased attention by researchers around ...

More efficient fuel cell applications via nanotechnology

Apr 14, 2011

(PhysOrg.com) -- Engineers at UC San Diego are using nanotechnology to increase the efficiency and enhance the performance of fuel cells, which could boost renewable energy options and reduce toxic emissions.

Recommended for you

Study shows graphene able to withstand a speeding bullet

16 hours ago

(Phys.org)—A team of researchers working at Rice University in the U.S. has demonstrated that graphene is better able to withstand the impact of a bullet than either steel or Kevlar. In their paper published ...

Nanomaterials to preserve ancient works of art

Nov 27, 2014

Little would we know about history if it weren't for books and works of art. But as time goes by, conserving this evidence of the past is becoming more and more of a struggle. Could this all change thanks ...

Learning anti-microbial physics from cicada

Nov 27, 2014

(Phys.org) —Inspired by the wing structure of a small fly, an NPL-led research team developed nano-patterned surfaces that resist bacterial adhesion while supporting the growth of human cells.

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.