Significance of redistribution reactions defected by in situ atomic force microscopy during early stages of fast scan rate redox cycling experiments at a solid 7,7,8,8-tetracyanoquinodimethane-glassy carbon electrode-aqueous (electrolyte) interface

Suarez, M; Bond, A; Compton, R

Journal article

Significance of redistribution reactions defected by in situ atomic force microscopy during early stages of fast scan rate redox cycling experiments at a solid 7,7,8,8-tetracyanoquinodimethane-glassy carbon electrode-aqueous (electrolyte) interface

Abstract:: The reduction of solid 7,7,8,8-tetracyanoquinodimethane (TCNQ) at an electrode-TCNQ-aqueous (electrolyte) is complex, irrespective of whether the solid on the electrode surface is attached by direct adherence or formed by electrochemical deposition. In order to understand the origin of reaction pathways that accompany the [TCNQ]0/- process, fast scan rate (0.1 Vs-1) redox cycling and potential step experiments on TCNQ mechanically attached to a glassy carbon electrode placed in aqueous solution containing 0.1 M electrolyte (KC1, CsCl, or Et4NCl) have been monitored by the technique of in situ atomic force microscopy (AFM). The shapes of cycling voltammograms are consistent with the presence of a mixture of diffusion and surface processes in the initial cycles. AFM results show that, during the early stage of the redox cycling experiments, electrochemical reduction of TCNQ to sparingly soluble TCNQ" is accompanied by a redistribution process. This rearrangement results in the transformation of arrays of almost amorphous solid to a lower energy microcrystalline state which has a more thin film-type appearance. When CsCl is the electrolyte, long needletype crystals are detected by the AFM method after long periods of redox cycling. The identity of the cation in the supporting electrolyte and the solubility of the reduced salt formed by reduction of TCNQ affect the nature of the voltammetry observed during early stages of redox cycling. When the redistribution process is completed and the stable crystalline phase is formed, the voltammetry of the [TCNQ]0/- couple is predominantly controlled by a nucleation-growth mechanism.

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APA Style

Suarez, M., Bond, A., & Compton, R. (1999). Significance of redistribution reactions defected by in situ atomic force microscopy during early stages of fast scan rate redox cycling experiments at a solid 7,7,8,8-tetracyanoquinodimethane-glassy carbon electrode-aqueous (electrolyte) interface. JOURNAL OF SOLID STATE ELECTROCHEMISTRY, 4(1), 24–33.

MLA Style

Suarez, M, et al. “Significance of Redistribution Reactions Defected by in Situ Atomic Force Microscopy during Early Stages of Fast Scan Rate Redox Cycling Experiments at a Solid 7,7,8,8-Tetracyanoquinodimethane-Glassy Carbon Electrode-Aqueous (Electrolyte) Interface.” JOURNAL OF SOLID STATE ELECTROCHEMISTRY, vol. 4, no. 1, 1999, pp. 24–33.

Chicago Style

Suarez, M, A Bond, and R Compton. 1999. “Significance of Redistribution Reactions Defected by in Situ Atomic Force Microscopy during Early Stages of Fast Scan Rate Redox Cycling Experiments at a Solid 7,7,8,8-Tetracyanoquinodimethane-Glassy Carbon Electrode-Aqueous (Electrolyte) Interface.” JOURNAL OF SOLID STATE ELECTROCHEMISTRY 4 (1): 24–33.
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