ﺳﻨﺘﺰ ﻧﺎﻧﻮذرات ﭘﺎﻻدﯾﻮم ﺑﺮ ﺑﺴﺘﺮ ﮔﺮاﻓﻦ دوﭘﻪ ﺷﺪه ﺑﺎ ﻧﯿﺘﺮوژن ﺑﺎ اﺳﺘﻔﺎده از اﺣﯿﺎ واﮐﻨﺶ اﮐﺴﯿﺪاﺳﯿﻮن ﮐﻨﻨﺪهﻫﺎي ﺳﺎزﮔﺎر ﺑﺎ ﻣﺤﯿﻂ زﯾﺴﺖ ﺑﻪ ﻣﻨﻈﻮر اﺳﺘﻔﺎده در اﺗﺎﻧﻮل

ﭼﮑﯿﺪه: در ﮐﺎر ﺣﺎﺿﺮ ﭘﺎﻻدﯾﻮم ﺑﺮ ﺑﺴﺘﺮ ﮔﺮاﻓﻦ دوﭘﻪ ﺷﺪه ﺑﺎ ﻧﯿﺘﺮوژن (Pd/NRGO) و در ﻏﯿﺎب ﻧﯿﺘﺮوژن (Pd/RGO) ﺑﺎ اﺳﺘﻔﺎده از ﭼﺎي ﺳﺒﺰ ﺑﻪ ﻋﻨﻮان اﺣﯿﺎ ﮐﻨﻨﺪه ﺳﺎزﮔﺎر ﺑﺎ ﻣﺤﯿﻂ زﯾﺴﺖ، ﺳﻨﺘﺰ ﺷﺪ. ﮔﺮاﻓﻦ اﮐﺴﺎﯾﺪ ﺑﻪ ﻋﻨﻮان ﺑﺴﺘﺮ ﺗﻮﺳﻂ روش ﻫﺎﻣﺮ ﺗﻬﯿﻪ ﺷﺪ، ﺳﭙﺲ Pd ﺑﺮ روي RGO ﺑﻪ روش ﺑﺎرورﺳﺎزي ﻗﺮار ﮔﺮﻓﺖ. ﺑﺮاي ﺗﻬﯿﻪ Pd/NRGO ﺑﻪ روش ﺑﺎرورﺳﺎزي از اوره ﺑﻪ ﻋﻨﻮان ﻣﻨﺒﻊ ﻧﯿﺘﺮوژن و روش اﻟﮑﺘﺮوﺷﯿﻤﯿﺎﯾﯽ ﺗﮏ ﻣﺮﺣﻠﻪاي اﺳﺘﻔﺎده ﺷﺪ ﺗﺎ اﯾﻨﮑﻪ اﺑﺘﺪا ﮔﺮاﻓﻦ دوﭘﻪ ﺷﺪه و ﺳﭙﺲ ﭘﺎﻻدﯾﻮم ﺑﺮ ﺑﺴﺘﺮ آن ﻗﺮار ﮔﺮﻓﺖ. ﺑﺮاي ﺑﺮرﺳﯽ اﻧﺪازه ﺻﻔﺤﺎت و ﻣﻮرﻓﻮﻟﻮژي ﺳﻄﺢ از ﻋﮑﺲ ﺑﺮداري ﻣﯿﮑﺮوﺳﮑﻮپ اﻟﮑﺘﺮوﻧﯽ ﻋﺒﻮري اﺳﺘﻔﺎده ﺷﺪ. ﻧﯿﺘﺮوژن ﻣﻮﺟﻮد در ﺳﺎﺧﺘﺎر Pd/NRGO ﺑﺎﻋﺚ ﭘﺮاﮐﻨﺪﮔﯽ ﺑﻬﺘﺮ ﻧﺎﻧﻮﻓﻠﺰات ﭘﺎﻻدﯾﻮم ﺑﺮ روي ﺳﻄﺢ ﮔﺮاﻓﻦ ﺷﺪه و از ﺗﺠﻤﻊ آنﻫﺎ ﺟﻠﻮﮔﯿﺮي ﮐﺮده اﺳﺖ. ﺑﺮاي ﺑﺮرﺳﯽ رﻓﺘﺎر ﮐﺎﺗﺎﻟﯿﺴﺘﯽ ﮐﺎﺗﺎﻟﯿﺴﺖﻫﺎ از ﺗﺴﺖ وﻟﺘﺎﻣﺘﺮي ﭼﺮﺧﻪاي (CV)، وﻟﺘﺎﻣﺘﺮي روﺑﺸﯽ ﺧﻄﯽ و ﮐﺮوﻧﻮآﻣﭙﺮوﻣﺘﺮي در ﻣﺤﯿﻂ ﻗﻠﯿﺎﯾﯽ اﺗﺎﻧﻮل ﺑﻬﺮه ﺑﺮده ﺷﺪه اﺳﺖ. NRGO ﻓﻌﺎﻟﯿﺖ ﮐﺎﺗﺎﻟﯿﺴﺘﯽ ﺑﻬﺘﺮي ﻧﺴﺒﺖ ﺑﻪ Pd/RGO ﺑﺮاي اﮐﺴﯿﺪاﺳﯿﻮن اﺗﺎﻧﻮل در ﻣﺤﯿﻂ ﻗﻠﯿﺎﯾﯽ از ﺧﻮد ﻧﺸﺎن ﻣﯽدﻫﺪ. وﯾﮋﮔﯽﻫﺎي اﻟﮑﺘﺮوﺷﯿﻤﯿﺎﯾﯽ Pd/RGO و Pd/NRGO ﺗﻮﺳﻂ ﺗﺴﺖ وﻟﺘﺎﻣﺘﺮي ﭼﺮﺧﻪاي در ﻣﺤﻠﻮل ﭘﺘﺎﺳﯿﻢ ﻫﯿﺪروﮐﺴﯿﺪ ﺑﻪ ﻣﻨﻈﻮر اﻧﺪازهﮔﯿﺮي ﺳﻄﺢ ﻓﻌﺎل ﮐﺎﺗﺎﻟﯿﺴﺖ و در ﻣﺤﻠﻮل اﺗﺎﻧﻮل و ﭘﺘﺎﺳﯿﻢ ﻫﯿﺪروﮐﺴﯿﺪ ﺑﺮاي ﺑﺮرﺳﯽ رﻓﺘﺎر ﭘﺎﻻدﯾﻮم در ﺑﺴﺘﺮ ﮔﺮاﻓﻨﯽ و ﺑﺴﺘﺮ ﮔﺮاﻓﻨﯽ ﻧﯿﺘﺮوژندار اﻧﺠﺎم ﺷﺪ. ﺑﺮاي ﺑﺮرﺳﯽ ﺑﯿﺸﺘﺮ رﻓﺘﺎرﻫﺎي اﻟﮑﺘﺮوﺷﯿﻤﯿﺎﯾﯽ از ﺗﺴﺖﻫﺎي وﻟﺘﺎﻣﺘﺮي روﺑﺸﯽ ﺧﻄﯽ ﺑﺮاي ﻣﻄﺎﻟﻌﻪ ﺳﯿﻨﺘﯿﮏ واﮐﻨﺶ ﮐﺎﺗﺎﻟﯿﺴﺖﻫﺎ و ﻧﯿﺰ ﺗﺴﺖ ﮐﺮوﻧﻮآﻣﭙﺮوﻣﺘﺮي ﺑﺮاي ﻣﻄﺎﻟﻌﻪ ﭘﺎﯾﺪاري ﻫﺮ دو ﮐﺎﺗﺎﻟﯿﺴﺖ اﺳﺘﻔﺎده ﺷﺪ. ﻧﺘﺎﯾﺞ ﻧﺸﺎن داد ﮐﻪ ﭘﺎﻻدﯾﻮم در ﺣﻀﻮر ﺑﺴﺘﺮ ﮔﺮاﻓﻨﯽ ﻧﯿﺘﺮوژندار در ﻣﻘﺎﯾﺴﻪ ﺑﺎ Pd/RGO داﻧﺴﯿﺘﻪ ﺟﺮﯾﺎن ﺑﺎﻻﺗﺮ، ﺷﯿﺐ ﺗﺎﻓﻞ ﮐﻤﺘﺮ و ﭘﺎﯾﺪاري ﺑﺎﻻﺗﺮي دار د.

This paper reportes fabrication of Pd /N-graphene (Pd/NRGO) catalyst through a one-step strategy, for the ethanol oxidation in alkaline media in order to use in direct ethanol fuel cell. Graphene oxide is synthesized via modified hummer method by using graphite powder and chemical agents. Pd nanoparticles then was reduced on graphene by green tea solution by making use of the reducing capability and the aromatic rings of tea polyphenol (TP) that contained in tea in presence and absence of urea as N-dopant agent source to obtain Pd/NRGO and Pd/RGO. The electrochemical characteristics of the Pd/NRGO and Pd/RGO catalysts are investigated by cyclic voltammetry (CV) in nitrogen saturated alkaline aqueous solution and in mixed alkaline and ethanol aqueous solutions to obtain electrochemical active surface area and onset potential. Detailed electrochemical studies (involving chronoamperometry, cyclic voltammetry and linear sweep voltammetry) prove that the electro-catalytic oxidation of ethanol in alkaline media at the Pd/NRGO is more stable, occurring at lower potential, higher active surface area, giving lower Tafel slopes compared to Pd/RGO catalyst, which can reveal the particular properties of the nitrogen supports and Pd nanoparticles.