Pulse cyclic voltammetry. I. Static solutions

Abstract

This paper is dedicated to Professor Douglas E. Ryan on the occasio~l of his 65th birthdayGORDON N. ECCLES and WILLIAM C. PURDY. Can. J. Chem. 65, 105 1 (1987).By using pulse cyclic voltammetry rather than cyclic voltammetry at a relatively high scan rate, an increase in sensitivity and a lowering of the detection limit by more than a factor of two are demonstrated for the ferricyanide-ferrocyanide couple at a carbon electrode. The test for reversibility based on peak shape or symmetry comparison is enhanced significantly with pulse cyclic voltammetry. Another reversibility test, by observing peak variations as a function of scan rate, was applied to pulse cyclic voltammetry and was found to be as diagnostically informative as the cyclic voltammetry test. These tests are illustrated by a study of the hydroquinone-quinone couple. Dans le cas du couple ferricyanure/ferrocyanure ii une electrode de carbone, on dCmontre que l'utilisation de la voltamCtrie cyclique pulsCe plut6t que la voltamCtrie cyclique B des taux de balayage relativement ClevCs augmente la sensibilitC et diminue la limite de detection par un facteur qui est plus grand que deux. Avec la voltamCtrie cyclique, on augmente considCrablement le test pour la rCversibilitC qui est bask sur la forme du maximum ou sur une comparaison de la symCtrie. On a aussi appliquC un autre test de rCversibilitC, bask sur les variations des maxima observCs en fonction du taux de balayage, B la voltamktrie pulsCe et on a trouvC que ce test permet un aussi bon diagnostique que le test de la voltamCtrie cyclique. On illustre ces tests par une Ctude du coupe hydroquinone/quinone.[Traduit par la revue]

Pulse cyclic voltammetry. II. Flowing solutions

“…In static solutions it was found that the residual current becomes reproducible after completion of the first cycle during a multiple scan CV (16). This behaviour is also observed in flowing streams and is illustrated by the results of a multiple scan CV of a 20 pL injection of 1 mM quinone in 1 M sulfuric acid shown in Fig.…”

“…In spite of this disadvantage, a wealth of voltammetric information can be obtained by applying a pulse cyclic voltammetric waveform as the excitation signal (15,16). This work will show some of the merits achieved when applying this waveform to an LTIC electrode in flow-injection analysis (FlA) using the hydroquinone-quinone couple.…”

Cyclic Square Wave Voltammetry of Single and Consecutive Reversible Electron Transfer Reactions

“…In this work, we explore a composite waveform for the evaluation and identification of electron transfer mechanisms, i.e., cyclic square wave voltammetry. , This waveform utilizes a square wave which steps through the region of the formal potential of the electroactive species under study in two directions. Although there is strong literature precedent for cyclic pulse techniques, − only a few reports on CSWV have appeared. ,,,− We believe the use of this waveform merits consideration for several reasons. First, the utilization of the square wave potential waveform and the discrete current sampling regimen will permit mechanistic evaluations at trace levels.…”

“…9,10 This waveform utilizes a square wave which steps through the region of the formal potential of the electroactive species under study in two directions. Although there is strong literature precedent for cyclic pulse techniques, [11][12][13][14][15][16][17] only a few reports on CSWV have appeared. 9,10,16,[18][19][20][21][22][23][24][25][26][27][28] the use of this waveform merits consideration for several reasons.…”