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Supporting Information
CVD graphene transfer procedure introduces metallic impurities which
alter the graphene electrochemical properties
Adriano Ambrosi, Martin Pumera*
a Division of Chemistry & Biological Chemistry, School of Physical and Mathematical
Sciences, Nanyang Technological University, Singapore 637371, Singapore.
Fax: (65) 6791-1961, Email: [email protected]; [email protected]
Electronic Supplementary Material (ESI) for NanoscaleThis journal is © The Royal Society of Chemistry 2014
Figure bottom pwhich fua securemm2 forelectrodelectrodinvestigagraphenreferenc
S1. Schemapart where thunctions as re and sealed r the CVD-Ge while a Pte, respectiveated. A Cu e and the vo
ce electrode.
atic of the elhe metal/CV
reservoir. A rchamber to b
Graphene samt and Ag/Agely. The siz
tape was uoltammetric i
lectrochemicVD-graphenerubber o-ringbe filled witmple to be egCl wire immze of the o-used to ensuinstrument. A
2
cal cell usede sample is pg (I.D. = 4.5 th the measuexamined. Tmersed in th-ring definesure the elecAll electroch
d for the meplaced; and a
mm; O.D. =urement soluthe metal/CV
he solution as the portionctrical connehemical pote
easurements. an upper par= 8.1 mm) antion for a tot
VD-graphenect as the auxn of the CVection betweentials are sta
It consists rt with a connd four screwtal surface are acts as the xiliary and r
VD-grapheneeen the metated versus A
of a flat nical hole ws ensure rea of 17 working
reference e surface tal/CVD-Ag/AgCl
Electronic Supplementary Material (ESI) for NanoscaleThis journal is © The Royal Society of Chemistry 2014
Figure Swater toand the sconfirme
S2. STEM im remove excspectra are ped the contam
mages of diffess FeCl3 so
presented cormination from
ferent samplelution. EDX
rrespondinglym the Fe bas
3
es of CVD-gX analyses we
y. In both cased etching s
graphene afteere performeases, Fe impusolution.
er the washind on the enti
urities were d
ng steps in diire area illustdetected whic
istilled trated ch
Electronic Supplementary Material (ESI) for NanoscaleThis journal is © The Royal Society of Chemistry 2014
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Figure S3. One hundred successive cyclic voltammograms recorded in 0.1 M NaOH solution using A) Ni foil and B) CVD-graphene transferred onto a glass slide. Successive potential scans resulted in the thickening of Ni(OH)2 layer on the Ni metal surface which was then electrochemically oxidized and reduced. The increment of both the oxidative and reductive signals is common when Ni foil is adopted as a working electrode. When the transferred CVD-graphene was used as electrode, the same phenomenon occurred although at much lower scale due to the fact that only residual amount of Ni impurities were present.
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Electronic Supplementary Material (ESI) for NanoscaleThis journal is © The Royal Society of Chemistry 2014