39 2 94 1 15 1 [Cu(terpy)] 2+ ph [Cu(terpy)] 2+ [Cu(terpy)] 2+ -0.80 V ph [Cu(terpy)] 2+ 1.1 10-3 M [Cu(terpy)] 2+ 0.17 V 35 A [Cu(terpy)] 2+ Levich [Cu(terpy)] 2+ [Cu(terpy)] 2+ (oxygen reduction)(electrocatalysis) (fossil fuels) [1]
2 (electron transfer materials) Anson [2-6 ] [7] [8,9] (pyrolytic graphite) (amorphous) [Cu(phen) 2 ] 2+ [10] [Cu(phen) 2 ] 2+ Bhugun Anson[11] [Co(tim)] 2+ ( tim 2,3,9,10-tetramethyl -1,4,8,11-tetraazacyclotetradeca -1,3,8,10-tetraene) [Co(tim)] + 2 ads [Co(tim)] 2+ [Cu(terpy)] 2+ [Cu(terpy)] 2+ [Cu(terpy)] 2+ [Cu(terpy)] 2+ ph [Cu(terpy)] 2+ Cu(terpy)(CF 3 SO 3 ) 2 [12] Cu(CF 3 SO 3 ) 2 (Merck)terpy (Aldrich)1 1 (acetonitrile) (Merck) (Merck) 2 24 Cu(terpy)(CF 3 SO 3 ) 2 Cu(C 15 H 11 N 3 )(CF 3 SO 3 ) 2 Perkin-Elmer 240C EA CuC 17 H 15 N 3 F 6 S 2 O 8 2 C 33.30%, H 2.12%, N 6.85%, C 33.75%, H 2.08%, N 6.05% 0.1M H 3 PO 4 (Merck) NaOH (Merck) ph (99.95%) (2,2,2 -terpyridine) (BAS,MF-2066) 0.5 m
3 BAS (Bio-analytical System) 100B/W/ (BAS,RE-5B) 0.35 mm (counter electrode) /+0.20 ~ -0.80 V 100 mvs -1 25.0 0.1 N 2 O 2 ( BÜCHI FONTAVAPOR 285) [Cu(terpy)] 2+ 5.0 10-5 M -0.30 V~ 1-.00 V-0.10 V 100 mvs -1 [Cu(terpy)] 2+ I A /I C II A /II C [13] I A /I C [Cu II (terpy) (OH 2 )] 2+ /[Cu I (terpy)(oh 2 )] + II A /II C [Cu II (terpy)(oh 2 ) 2 ] 2+ /[Cu I (terpy)(oh 2 ) 2 ] + -1.00 V 4.11 A[Cu(terpy)] + Cu (s) [Cu(terpy)] (ads) [Cu(terpy)] 2+ -1.00V a ab b 5.0 10-5 M [Cu(terpy)] 2+ 0.1M [Cu(terpy)] 2+ 5.0 10-5 M ph100mv s -1 a b cph 5.30 7.52 10.60 a b c ph I A II A II A ph [13] [Cu(terpy)] 2+ [Cu(terpy)] + I A ph [Cu(terpy)] + II A phph [OH - ] OH - H 2 O OH - [Cu(terpy)] 2+ [Cu(terpy)] + OH - I A ph II A ph [14]
4 [Cu(terpy)] 2+ 0.1 M(pH=5.30)5.0 10-5 M -0.30-0.40-0.50-0.60-0.70-0.80-0.90-1.00 V 1.1 10-3 M [Cu(terpy)] 2+ 0.1 M ph 5.3 a b [Cu(terpy)] 2+ -0.40V -0.58 V 75 A 40 A a [Cu(terpy)] 2+ /[Cu(terpy)] + ( I C ) [Cu(terpy)] 2+ [Cu(terpy)] + -0.03 V b -0.20 V [Cu(terpy)] + 0.17 V [Cu(terpy)] 2+ ( II C ) [Cu(terpy)] +
5 a 5.0 10-5 M [Cu(terpy)] 2+ 0.1 M(pH=5.30) 10 50 100 200 300 mvs -1 b IIc I A :II C : II A : [Cu(terpy)] + [Cu(terpy)] 2+ 0.1 M ph 5.3 a b [Cu(terpy)] 2+ [Cu(terpy)] 2+ 5.0 10-4 M [Cu(terpy)] 2+ [Cu(terpy)] 2+ 1.0 10-4 M [Cu(terpy)] 2+ ([Cu(terpy)] + ) [Cu(terpy)] + - ([Cu(terpy)] + -O 2 ) [Cu(terpy)] 2+ [Cu(phen) 2 ] 2+ [10] ([Cu(terpy)] + ) [Cu(terpy)] 2+ [Cu(terpy)] 2+/+ [Cu(terpy)] 2+ [Cu(terpy)] 2+ [Cu(terpy)] 2+/+
6 0.1 M [Cu(terpy)] 2+ 5.0 10-5 M ph100 mvs -1 a b c ph 5.30 7.52 10.60
7 a 0.1 M ph 5.325 [Cu(terpy)] 2+ 1.1 10-3 M 100 mvs -1 b [Cu(terpy)] 2+ (1)(2) a 0.1 M ph 5.325 100mVs -1 [Cu(terpy)] 2+ (1) 0 M(2) 5.0 10-5 M (3) 1.0 10-4 M (4)5.0 10-4 M (5)1.1 10-3 M b [Cu(terpy)] 2+
8 [Cu(terpy)] 2+ [13] [Cu(terpy)] 2+ 1.1 10-3 M [Cu(terpy)] 2+ [Cu(terpy)] 2+ [Cu(terpy)] 2+ [Cu(terpy)] 2+ ph=5.3 0.1 M 100 mvs 1 [Cu(terpy)] 2+ 1.1 10-3 M (1) (2) (3) 0.1 M ph 5.3 [Cu(terpy)] 2+ 0 M 5.0 10-5 M 5.0 10-4 M 10 mvs -1 (10 mvs -1 ) [Cu(terpy)] 2+ ([Cu(terpy)] + /[Cu(terpy)] 2+ ) (f) (f )0.20 ~ -0.80 V (background curret) S (sigmoid wave) [Cu(terpy)] 2+ 5.0 10-5 M [Cu(terpy)] 2+ [Cu(terpy)] 2+ A A [Cu(terpy)] + B
9 ( B)b5.0 10-5 M [Cu(terpy)] 2+ [Cu(terpy)] 2+ A B5.0 10-4 M [Cu(terpy)] 2+ [Cu(terpy)] + 0.1 M ph 5.3 25 10 mvs -1 0.20 V~ -0.80 V : (a) 500 (b) 1000 (c) 1500 (d) 2000 (e) 2500 (f) 3000 (g) 3500 (h) 4000 rpm (f ) 3000 rpm 0.1 M ph 5.3 [Cu(terpy)] 2+ 5.0 10-5 M 25 10 mvs -1 0.20 V~ -0.80 V
10 0.1 M ph 5.3 [Cu(terpy)] 2+ 5.0 10-4 M 25 10 mvs -1 0.20 V~ -0.80 V [15] Levich Koutecký-Levich (i L ) Levich [16] : i L =0.62nFADo 2/3-1/6 1/2 C b (5-1) (5-1 ) nf (96500 Cmole -1 ) C b (1.103 10-3 M)[17] Do (1.76 10-5 cm 2 s -1 ) [17] 0.01 cm 2 s -1 Levich-0.75 V n=2 n=4 (5-1) Levich [18] Levich line n=4 5.0 10-4 M [Cu(terpy)] 2+
11 Levich0.1 M ph 5.325 (E L =-0.75V) [Cu(terpy)] 2+ 5.0 10-4 M n=2 n=4 (5-1) 1 Koutecký-Levich[19]: 1 i 1 1 = + i k 0.62nFD 2/3 C b -1/6 1/2 (5-2) (5-2) n i k (5-1) i -1-1/2 a b c [Cu(terpy)] 2+ 0 5.0 10-5 5.0 10-4 M n=2 n=4 (5-2) a b c i -1-1/2 (5-2) 1 [20,21] a b c [Cu(terpy)] 2+ 5.0 10-5 M 5.0 10-4 M [Cu(terpy)] 2+ 5.0 10-5 M 5.0 10-4 M -0.30 V [Cu(terpy)] 2+ 5.0 10-5 M A B A [Cu(terpy)] + B b [Cu(terpy)] 2+ Anson[22]
12 0.1 M ph 5.325 [Cu(terpy)] 2+ (a)0 M (b)5.0 10-5 M (c) 5.0 10-4 M n=2 n=4 (5-2) :
13 ( ) 0.30, ( ) 0.40, ( ) 0.50, ( ) 0.60, ( ) 0.70 V E log[i/(i L -i)] E log[i/(i L -i)] 3000 rpm i L -0.75 V E log[i/ (i L -i)] [Cu(terpy)] 2+ [Cu(terpy)] 2+ 5.0 10-5 M 5.0 10-4 M -0.117-0.107 Vdec -1-120 Vdec -1 (first one-electron transfer) -6 0 Vdec -1 [20,21,23] 5-13 [Cu(terpy)] 2+ [Cu(terpy)] 2+ 0.1 M ph 5.325 3000 rpm -0.75 V E log[i/(i L -i)] [Cu(terpy)] 2+ (1)5.0 10-5 M (2) 5.0 10-4 M [Cu(terpy)] 2+ -0.80 V ph [Cu(terpy)] 2+ 0.1 M ph 5.3 [Cu(terpy)] 2+ 1.1 10-3 M [Cu(terpy)] 2+ 0.17 V 35 A Lecivh [Cu(terpy)] 2+
14 [Cu(terpy)] 2+ Tafel 1 T. Abe, J. Kubota, T. Tanaka, K. Shoji and A. Tajiri, Electrochim. Acta, 47 (2002) 3901. 2 J. Zhang and F. C. Anson, J. Electroanal. Chem., 341 (1992) 323. 3 A. L. B. Marques, J. Zhang, A. B. P. Lever and W. J. Pietro, J. Electroanal. Chem., 392 (1995) 43. 4 J. Zhang and F. C. Anson, Electrochim. Acta, 38 (1993) 2423. 5 Y. Lei and F. C. Anson, Inorg. Chem., 33 (1994) 5003. 6 Y. Lei and F. C.Anson, Inorg. Chem., 34 (1995) 1083. 7 J. Zhang and F. C. Anson, J. Electroanal. Chem., 353 (1993) 265. 8 I. Bhugun and F. C. Anson, J. Electroanal. Chem., 430 (1997) 155. 9 C. knag, Y. Xie and F. C. Anson, J. Electroanal. Chem., 413 (1996) 165. 0 S. J. Liu, C. H. Huang, C. C. Chang, Mat. Chem. Phys., 82 (2003) 551. q I. Bhugun and F. C. Anson, Inorg. Chem. 35 (1996) 7253. w B. Hathawa, Comprehensive Coordination Chemistry, vol.5.(1987). e 38 (2004) 61 r M. A. Augustion and J. K. Yandell, Inorg Chem., 18 (1979) 577. t E. Yeager, Electrochimica. Acta, 29 (1984) 1527. y V. G. Levich, Physicochemical Hydrodynanics, Prentice Hall. Englewood Cliffs, N. J. (1962). u K. Z. Gubbins and R. D. Walker, Jr, J. Electrochem. Soc., 112 (1965) 469. i E. M. Choi, H. Jeog, D. H. Park, Y. K. Choi and S. Jeon, Bull. Korea Chem. Soc., 20 (1999) 1056. o V. G. Levich, Physicochemical Hydrodynanics, Prentice Hall. Englewood Cliffs, N. J. (1962). p N. M. Markovic, R. R. Adzic, B. D. Cahan and E. B. Yeager, J. Electroanal. Chem., 377 (1994) 249. a J. H. Zagal, M. J. Aguirre and M. A. Paez, J. Electroanal. Chem., 437 (1997) 45. s F. C. Anson () (1981) p.158 d C. A. Caro, F. Bedioui and J. H. Zagal, Electrochim. Acta, 47 (2001) 1489.
15 Electrocatalytic Reduction Oxygen with Cu(II) Complex of 2,2,2 -terpyridine at Glassy Carbon Electrode. Department of Nature Science Education, National University of Tainan Institute of Environment and Ecology, National University of Tainan Abstract This study investigated the electrocatalytic reduction oxygen with copper (II) complex of 2,2,2 -terpyridine. [Cu(terpy)] 2+ ( terpy, where is 2,2,2 -terpyridine) was studied in phosphate buffer solutions at a glassy carbon electrode. Cyclic voltammetry was scanned in different low limiting potential. The results indicated that the working limiting potential was 0.80V vs. Ag/ AgCl reference electrode. In different ph phosphate buffer solutions, the cyclic voltammetric curves indicated the coordination number of [Cu(terpy)] 2+ was mainly five. Cyclic voltammetric results indicated that the oxygen reduction was catalyzed by [Cu(terpy)] 2+/+ (1.1 10-3 M) transition in phosphate solutions at a glassy carbon electrode. The onset potentials of oxygen reduction shift ca. 0.17V negatively and a enhancement of peak current ca. 35µA. Only the absorbed [Cu(terpy) 2+ ] was an active catalyst for oxygen reduction. According to the Levich plots and apparent number of electrons exchange per O 2 molecular, the oxygen reduction proceeded via four electrons to give water. Tafel slope was increased with adsorption amount of [Cu(terpy)] 2+ on the glassy carbon electrode surface. A change of fafel slope implied a change in the rate-determining step on oxygen reduction reaction. Key word: copper complex, oxygen reduction, electrocatalysis
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