TY - JOUR
T1 - Monothiolation and Reduction of Graphene Oxide via One-Pot Synthesis
T2 - Hybrid Catalyst for Oxygen Reduction
AU - Chua, Chun Kiang
AU - Pumera, Martin
N1 - Publisher Copyright:
© 2015 American Chemical Society.
Copyright:
Copyright 2015 Elsevier B.V., All rights reserved.
PY - 2015/4/28
Y1 - 2015/4/28
N2 - The functionalization of graphene provides diverse possibilities to improve the handling of graphene and enable further chemical transformation on graphene. Graphene functionalized with mainly heteroatom-based functional groups to enhance its chemical and physical properties is intensively pursued but often resulted in grafting of the heteroatoms as various functional groups. Here, we show that graphene oxide can be functionalized with predominantly a single type of sulfur moiety and reduced simultaneously to form monothiol-functionalized graphene. The thiol-functionalized graphene shows a high electrical conductivity and heterogeneous electron transfer rate. Graphene is also embedded with a trace amount of manganese impurities originating from a prior graphite oxidation process, which facilitates the thiol-functionalized graphene to function as a hybrid electrocatalyst for oxygen reduction reactions in alkaline medium with an onset potential lower than for Pt/C. Further characterizations of the graphene are performed with X-ray photoelectron spectroscopy, scanning electron microscopy with energy-dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis, Raman spectroscopy, and electrochemical impedance spectroscopy. This material contributes to the class of hybrids that are highly active electrocatalysts.
AB - The functionalization of graphene provides diverse possibilities to improve the handling of graphene and enable further chemical transformation on graphene. Graphene functionalized with mainly heteroatom-based functional groups to enhance its chemical and physical properties is intensively pursued but often resulted in grafting of the heteroatoms as various functional groups. Here, we show that graphene oxide can be functionalized with predominantly a single type of sulfur moiety and reduced simultaneously to form monothiol-functionalized graphene. The thiol-functionalized graphene shows a high electrical conductivity and heterogeneous electron transfer rate. Graphene is also embedded with a trace amount of manganese impurities originating from a prior graphite oxidation process, which facilitates the thiol-functionalized graphene to function as a hybrid electrocatalyst for oxygen reduction reactions in alkaline medium with an onset potential lower than for Pt/C. Further characterizations of the graphene are performed with X-ray photoelectron spectroscopy, scanning electron microscopy with energy-dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis, Raman spectroscopy, and electrochemical impedance spectroscopy. This material contributes to the class of hybrids that are highly active electrocatalysts.
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U2 - 10.1021/acsnano.5b00438
DO - 10.1021/acsnano.5b00438
M3 - Article
AN - SCOPUS:84928967050
VL - 9
SP - 4193
EP - 4199
JO - ACS Nano
JF - ACS Nano
SN - 1936-0851
IS - 4
ER -