Modeling the Electrochemical Impedance Spectra of Electroactive Pseudocapacitor Materials

被引:24
作者
Nilson, Robert H. [1 ]
Brumbach, Michael T. [2 ]
Bunker, Bruce C. [2 ]
机构
[1] Sandia Natl Labs, Livermore, CA 94550 USA
[2] Sandia Natl Labs, Albuquerque, NM 87185 USA
基金
美国能源部;
关键词
CHARGE STORAGE MECHANISM; RESISTIVITY DISTRIBUTIONS; INTERCALATION PARTICLES; ELECTRICAL-PROPERTIES; RUTHENIUM DIOXIDE; AQUEOUS-SOLUTION; RUO2; ELECTRODES; HYDROUS RUO2; AC RESPONSE; BEHAVIOR;
D O I
10.1149/1.3561427
中图分类号
O646 [电化学、电解、磁化学];
学科分类号
081704 ;
摘要
Measured electrochemical impedance spectra of porous electrodes comprised of redox-active ruthenium oxide and inert niobium hydroxide are compared with the results of structurally consistent mathematical models describing coupled processes of electron transport in the solid matrix, ion transport in the electrolyte, proton transport within the ruthenium oxide particles, and redox reaction on particle surfaces. Addition of moderate amounts of niobium to crystalline ruthenium oxide is found to improve the frequency response due to enhanced intraparticle proton transport. However, excessive niobium reduces ion and electron transport through the electrode thickness, reducing the available capacitance. Thus, an optimum composition is needed to achieve the best balance in transport properties. Near this optimum, the intraparticle proton transport undergoes a transition from a constant phase element (CPE) response for Ru-rich materials to a classical Warburg diffusion response for Nb-rich compositions. The CPE regime is analyzed in detail to identify fractal-like structures as well as alternative radial distributions of intraparticle proton diffusivity consistent with measured response. The models involving variations in radial diffusivity appear most probable and have nearly exponential decreases in radial diffusivity with distance from particle surfaces similar to a Debye distribution of charge carriers in an electric double layer. (C) 2011 The Electrochemical Society. [DOI: 10.1149/1.3561427]
引用
收藏
页码:A678 / A688
页数:11
相关论文
共 40 条
[1]  
[Anonymous], 1999, ELECTROCHEMICAL SUPE
[2]   INNER AND OUTER ACTIVE SURFACE OF RUO2 ELECTRODES [J].
ARDIZZONE, S ;
FREGONARA, G ;
TRASATTI, S .
ELECTROCHIMICA ACTA, 1990, 35 (01) :263-267
[3]   Effect of electronic resistance and water content on the performance of RuO2 for supercapacitors [J].
Barbieri, O. ;
Hahn, M. ;
Foelske, A. ;
Koetz, R. .
JOURNAL OF THE ELECTROCHEMICAL SOCIETY, 2006, 153 (11) :A2049-A2054
[4]   Ruthenium oxide-niobium hydroxide composites for pseudocapacitor electrodes [J].
Brumbach, Michael T. ;
Alam, Todd M. ;
Nilson, Robert H. ;
Kotula, Paul G. ;
McKenzie, Bonnie B. ;
Tissot, Ralph G. ;
Bunker, Bruce C. .
MATERIALS CHEMISTRY AND PHYSICS, 2010, 124 (01) :359-370
[5]   TRANSITION FROM SUPERCAPACITOR TO BATTERY BEHAVIOR IN ELECTROCHEMICAL ENERGY-STORAGE [J].
CONWAY, BE .
JOURNAL OF THE ELECTROCHEMICAL SOCIETY, 1991, 138 (06) :1539-1548
[6]  
de Levie R., 1963, Electrochim. Acta, V8, P751, DOI [DOI 10.1016/0013-4686(64)85015-5, DOI 10.1016/0013-4686(63)80042-0]
[7]   FRACTALS AND ROUGH ELECTRODES [J].
DELEVIE, R .
JOURNAL OF ELECTROANALYTICAL CHEMISTRY, 1990, 281 (1-2) :1-21
[8]   Local atomic structure and conduction mechanism of nanocrystalline hydrous RuO2 from X-ray scattering [J].
Dmowski, W ;
Egami, T ;
Swider-Lyons, KE ;
Love, CT ;
Rolison, DR .
JOURNAL OF PHYSICAL CHEMISTRY B, 2002, 106 (49) :12677-12683
[9]   Effect of surface structure on behavior of RuO2 electrodes in sulfuric acid aqueous solution [J].
Doubova, LA ;
De Battisti, A ;
Daolio, S ;
Pagura, C ;
Barison, S ;
Gerbasi, R ;
Battiston, G ;
Guerriero, P ;
Trasatti, S .
RUSSIAN JOURNAL OF ELECTROCHEMISTRY, 2004, 40 (11) :1115-1122
[10]   Examination of RuO2 single-crystal surfaces:: charge storage mechanism in H2SO4 aqueous solution [J].
Doubova, LM ;
Daolio, S ;
De Battisti, A .
JOURNAL OF ELECTROANALYTICAL CHEMISTRY, 2002, 532 (1-2) :25-33