چكيده به لاتين
Fuel cells have enjoyed a rising popularity in recent years, which is mainly due to their zero to no emission, high energy conversion efficiency and the absence of any moving parts in their structure. The direct methanol fuel cell (DMFC) is a promising candidate for powering portable electronic devices such as laptops, digital cameras and cell phones. Compared with conventional batteries, DMFCs could provide a higher power density with a longer lifetime and almost instant recharging. Liquid methanol, as an excellent electrochemical energy source, is suitable for developing DMFCs and is highly promising as a future power solution for the transportation industry.
In this study graphene supported palladium (G-Pd), silver (G-Ag) and bimetallic palladium- silver (G-PdAg) nanocatalysts were electrodeposited in situ and via a one-step procedure on carbon cloth and their electrocatalytic activities towards methanol oxidation in alkaline media were investigated. Furthermore, G-PdAg nanocatalysts on carbon cloth (G-PdAg/CC) with different Pd to Ag loading ratios (G-PdAg(m:n)/CC) were prepared using the same one-step and in situ electrodeposition method and the electrocatalytic performance towards methanol oxidation in alkaline solution was investigated.
The results indicate, that although G-Ag/CC itself shows no significant activity for methanol electrooxidation, Ag is capable of promoting Pd in its electrochemical activity towards methanol oxidation reaction. The as-prepared modified G-PdAg(1:1)/CC electrode demonstrates greatly enhanced peak current density (1300 mA/mgPd), lower on-set potential of methanol oxidation (-0.68 V), improved resistance against poisoning effect of carbonaceous species fomed during methanol oxidation and better stability for MOR.
