Slow Diffusion Reveals the Intrinsic Electrochemical Activity of Basal Plane Highly Oriented Pyrolytic Graphite Electrodes

被引:49
作者
Edwards, Martin A. [1 ,2 ]
Bertoncello, Paolo [1 ]
Unwin, Patrick R. [1 ]
机构
[1] Univ Warwick, Dept Chem, Coventry CV4 7AL, W Midlands, England
[2] Univ Warwick, MOAC Doctoral Training Ctr, Coventry CV4 7AL, W Midlands, England
关键词
LANGMUIR-BLODGETT-FILMS; WALLED CARBON NANOTUBES; TRANSFER KINETICS; METAL NANOPARTICLES; SCHAEFER FILMS; POLYMER-FILMS; NAFION FILMS; ACTIVATION; PERFORMANCE; MICROSCOPY;
D O I
10.1021/jp8092918
中图分类号
O64 [物理化学(理论化学)、化学物理学];
学科分类号
070304 ; 081704 ;
摘要
This paper reports a method for distinguishing the electroactivity of different types of sites on heterogeneous electrode surfaces, exemplified through studies of basal plane highly oriented pyrolytic graphite (HOPG) electrodes. By depositing a thin film of Nafion with incorporated redox species (i.e., tris(2-2'-bipyridyl)ruthenium(II), Ru(bpy)(3)(2+), and hexaaminoruthenium(III), [Ru(NH3)(6)](3+) onto HOPG, diffusion is greatly slowed down. On the time scale of cyclic voltammetry, one can then distinguish between different scenarios of electrode activity because sites on the electrode, with different activity, become diffusionally decoupled. In particular, we show that one can discriminate readily between limiting cases in which the basal plane of HOPG is considered to be either (i) completely active or (ii) inert (with only step edges active). Experimental measurements coupled to modeling show unequivocally that the basal plane of HOPG is electrochemically active. The methodology described and the results obtained have important implications for understanding the intrinsic activity of the basal plane and step edges of graphite electrodes and related carbon-based electrode materials.
引用
收藏
页码:9218 / 9223
页数:6
相关论文
共 48 条
[11]  
Bertoncello P, 2007, J PHYS CHEM C, V111, P294, DOI [10.1021/jp065398l, 10.1021/jp0653981]
[12]   Measurement of apparent diffusion coefficients within ultrathin Nafion Langmuir-Schaefer films: Comparison of a novel scanning electrochemical microscopy approach with cyclic voltammetry [J].
Bertoncello, Paolo ;
Ciani, Ilenia ;
Li, Fei ;
Unwin, Patrick R. .
LANGMUIR, 2006, 22 (25) :10380-10388
[13]   MECHANISM OF ELECTROCHEMICAL ACTIVATION OF CARBON ELECTRODES - ROLE OF GRAPHITE LATTICE-DEFECTS [J].
BOWLING, R ;
PACKARD, RT ;
MCCREERY, RL .
LANGMUIR, 1989, 5 (03) :683-688
[14]   ACTIVATION OF HIGHLY ORDERED PYROLYTIC-GRAPHITE FOR HETEROGENEOUS ELECTRON-TRANSFER - RELATIONSHIP BETWEEN ELECTROCHEMICAL PERFORMANCE AND CARBON MICROSTRUCTURE [J].
BOWLING, RJ ;
PACKARD, RT ;
MCCREERY, RL .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1989, 111 (04) :1217-1223
[15]   ELECTRON-TRANSFER KINETICS AT MODIFIED CARBON ELECTRODE SURFACES - THE ROLE OF SPECIFIC SURFACE SITES [J].
CHEN, PH ;
FRYLING, MA ;
MCCREERY, RL .
ANALYTICAL CHEMISTRY, 1995, 67 (18) :3115-3122
[16]   ANOMALOUSLY SLOW-ELECTRON TRANSFER AT ORDERED GRAPHITE-ELECTRODES - INFLUENCE OF ELECTRONIC FACTORS AND REACTIVE SITES [J].
CLINE, KK ;
MCDERMOTT, MT ;
MCCREERY, RL .
JOURNAL OF PHYSICAL CHEMISTRY, 1994, 98 (20) :5314-5319
[17]   Electrochemical templating of metal nanoparticles and nanowires on single-walled carbon nanotube networks [J].
Day, TM ;
Unwin, PR ;
Wilson, NR ;
Macpherson, JV .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 2005, 127 (30) :10639-10647
[18]   Single-walled carbon nanotube network ultramicroelectrodes [J].
Dumitrescu, Ioana ;
Unwin, Patrick R. ;
Wilson, Neil R. ;
Macpherson, Julie V. .
ANALYTICAL CHEMISTRY, 2008, 80 (10) :3598-3605
[19]   Carbon materials for lithium-ion rechargeable batteries [J].
Flandrois, S ;
Simon, B .
CARBON, 1999, 37 (02) :165-180
[20]   Electrochemistry and electroanalytical applications of carbon nanotubes: A review [J].
Gong, KP ;
Yan, YM ;
Zhang, MN ;
Su, L ;
Xiong, SX ;
Mao, LQ .
ANALYTICAL SCIENCES, 2005, 21 (12) :1383-1393