TY - JOUR
T1 - Effects of oxidation and heat treatment of acetylene blacks on their electrochemical double layer capacitances
AU - Kim, Taegon
AU - Ham, Chulho
AU - Rhee, Choong Kyun
AU - Yoon, Seong Ho
AU - Tsuji, Masaharu
AU - Mochida, Isao
N1 - Funding Information:
The work performed in Japan was carried out partially within the framework of CREST program. The authors in Japan acknowledge the financial support of Japan Science and Technology Corporation (JST) of Japan. On the other hand, the work performed in Korea was supported by the Next Generation Growth Engine Program funded by the Korean Government (MOCIE) (100283558). The authors thank Denki Kagaku Co., Japan for the kind supply of the acetylene blacks used in this work.
PY - 2009/1
Y1 - 2009/1
N2 - Correlations between the electrochemical double layer capacitances of various acetylene blacks modified by surface oxidation and heat treatment, and their morphologies are presented. The acetylene blacks were different from each other in primary structural unit size (equivalent to mean particle diameter). They were oxidized in air at 300 °C for 1 h to produce graphene sheets protruding from the surfaces of the spherical particles. In addition, the surfaces of the acetylene blacks were modified by heat treatments from 1000 °C to 2800 °C, which resulted in a morphological change from surfaces covered with protruding graphene sheets to ones wrapped with basal planes of graphite. Correlations between the capacitances of the acetylene blacks and the observed morphologies showed that the surface covered with protruding graphene sheets was roughly 10 times more effective in capacitive charging than the surface of graphite basal planes. Specifically, the surface specific capacitance of the edged-graphene-sheet-covering surface was 146 mF/m2, while that of the basal-planes-wrapping surface was 16 mF/m2. It was concluded that the capacitances of the acetylene blacks were mainly defined by surface morphology, which were in turn influenced by structural unit size and degree of oxidation.
AB - Correlations between the electrochemical double layer capacitances of various acetylene blacks modified by surface oxidation and heat treatment, and their morphologies are presented. The acetylene blacks were different from each other in primary structural unit size (equivalent to mean particle diameter). They were oxidized in air at 300 °C for 1 h to produce graphene sheets protruding from the surfaces of the spherical particles. In addition, the surfaces of the acetylene blacks were modified by heat treatments from 1000 °C to 2800 °C, which resulted in a morphological change from surfaces covered with protruding graphene sheets to ones wrapped with basal planes of graphite. Correlations between the capacitances of the acetylene blacks and the observed morphologies showed that the surface covered with protruding graphene sheets was roughly 10 times more effective in capacitive charging than the surface of graphite basal planes. Specifically, the surface specific capacitance of the edged-graphene-sheet-covering surface was 146 mF/m2, while that of the basal-planes-wrapping surface was 16 mF/m2. It was concluded that the capacitances of the acetylene blacks were mainly defined by surface morphology, which were in turn influenced by structural unit size and degree of oxidation.
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U2 - 10.1016/j.carbon.2008.10.010
DO - 10.1016/j.carbon.2008.10.010
M3 - Article
AN - SCOPUS:56949087609
SN - 0008-6223
VL - 47
SP - 226
EP - 233
JO - Carbon
JF - Carbon
IS - 1
ER -