Abstract:
Ordered mesoporous carbon-supported gold
nanoparticles (Au/OMC) have been fabricated in one step
through a hard template method using gold nanoparticle intercalated mesoporous silica (GMS) to explore two different
catalytic properties, for example, electrocatalytic oxidation of
methanol and colorimetric determination of glutathione
(GSH). The catalytically inert but conducting nature of
mesoporous carbon (OMC) and promising catalytic activity
of gold nanoparticles (AuNPs) has inspired us to synthesize
Au/OMC. The as-prepared Au/OMC catalyst was charac terized by powder X-ray diffraction, N2 adsorption−
desorption, scanning electron microscopy, transmission
electron microscopy, energy-dispersive X-ray analysis-elemen tal mapping, and X-ray photoelectron spectroscopy. The characterization results indicate that AuNPs are uniformly distributed
on the surface of OMC. The conducting-OMC framework with a high surface area of Au/OMC provides superior transport of
electrons through the porous surface of carbon matrix and resulted in its high efficiency and stability as an electrocatalyst for the
oxidation of methanol in comparison to CMK-3, SBA-15, and GMS in alkaline medium. The efficiency of Au/OMC toward
methanol oxidation in alkaline medium is much higher in comparison to that in acidic medium. The lower value of If
/Ib in the
acidic medium in comparison to that in the alkaline medium clearly indicates that the oxidation process with Au/OMC as a
catalyst is much more superior in alkaline medium with better tolerance toward the accumulation of intermediate CO species
on the active surface area. Furthermore, the Au/OMC catalyst is successfully utilized for the detection and quantification of
GSH spectrophotometrically with a limit of detection value of 0.604 nM.