Highly stable pt ru nanoparticles supported on three-dimensional cubic ordere...suresh899
The cost of the catalysts used in the direct methanol fuel cell
poses a challenge to its widespread use as an energy efficient and environment
friendly fuel conversion technology. In this study, two types of highly ordered
mesoporous carbon CMK-8 (I and II) with high surface area and 3-D
bicontinuous interpenetrating channels were synthesized and deposited with
PtRu nanoparticles using the sodium borohydride reduction method. The
electrocatalytic capabilities for methanol oxidation were investigated using
cyclic voltammetry and chronoamperometry, and the results were compared
with that of PtRu deposited on Vulcan XC-72 using the same preparation
method as well as with commercial PtRu/C (E-TEK) catalyst. Pt Ru/CMK-8-I synthesized by the method developed in this work revealed an
outstanding specific mass activity (487.9 mA/mg) and superior stability
compared with the other supports, thus substantiating its potential to reduce
the costs of DMFC catalysts.
Electrooxidation of methanol on carbon supported pt ru nanocatalysts prepared...suresh899
Carbon Supported PtRu nanocatalysts have been prepared by simple impregnation reduction method in which Pt and Ru precursors are reduced by ethanol under reflux conditions for different reaction times. The prepared nanocatalysts were characterized by means of XRD, EDAX, ICP-AAS, FESEM and TEM. XRD analyses showed that all nanocatalysts exhibited f.c.c crystal structure, the structure characteristic for pure Pt, except for that reduced at prolonged reaction time of 4h which showed the presence of characteristic peak for Ru metal. The lattice constant calculations indicate that all catalysts are present in unalloyed phase and the average particle size as determined by TEM was in the range of 3.7 nm. The electrocatalytic activities and stability for the prepared nanocatalysts methanol electro-oxidation reaction (MOR) were studied by cyclic voltammetry. The catalysts prepared at 2h reduction time showed higher electrocatalytic activity in terms of mass specific activity and good stability over potential sweep for 100 cycles for methanol electro-oxidation. The results showed that the prepared nanocatalysts are considered as promising electrode catalyst (anode catalyst) for electro-oxidation of methanol in direct methanol fuel cells.
Performance of carbon nanofiber supported pd–ni catalysts for electro oxidati...suresh899
Carbon nanofibers (CNF) supported Pd–Ni nanoparticles have been prepared by chemical reduction
with NaBH4 as a reducing agent. The Pd–Ni/CNF catalysts were characterized by X-ray diffraction
(XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and electrochemical
voltammetry analysis. TEM showed that the Pd–Ni particles were quite uniformly distributed on the
surface of the carbon nanofiber with an average particle size of 4.0 nm. The electro-catalytic activity of
the Pd–Ni/CNF for oxidation of ethanol was examined by cyclic voltammetry (CV). The onset potential
was 200mV lower and the peak current density four times higher for ethanol oxidation for Pd–Ni/CNF
compared to that for Pd/C. The effect of an increase in temperature from 20 to 60 ◦C had a great effect on
increasing the ethanol oxidation activity.
