Osteryoung square wave voltammetry OSWV

In this solvent, using CV and Osteryoung square-wave voltammetry (OSWV) under high vacuum conditions at room temperature, Cgo displays a one-electron, chemically reversible oxidation wave at +1.26 V vs. Fc/Fc+. TBAPFe was used as the supporting electrolyte. Under the same conditions, the first one-electron oxidation of C70 occurs at +1.20 V, 60 mV more negative (easier to oxidize) than that of Cgo- Both oxidations are electrochemically quasireversible with A pp = 80 mV. In addition, a second oxidation wave is observed for C70 close to the limit of the solvent potential window at+1.75 V. However, this wave appears to be chemically irreversible (see Fig. 3) [36]. 

If the concentrations of the redox compounds in the solution or at the electrode surface are low, and better sensitivities are needed than those optimal for LSV and SCV, differential pulse (DPV), normal pulse (NPV) and Osteryoung square-wave voltammetries (OSWV) are more suitable [9a, 9b]. They allow better elimination of the capacitive/background currents and, therefore, the measurement of smaller faradic signals becomes easier. This is achieved either by sampling the current at the end of each pulse (OSWV, NPV) (Fig. 10.5.IE and F) or twice at the end and before pulse application (DPV) (Fig. 10.5.ID). 

One of us had previously report Ae Osteryoung Square Wave Voltammetry (OSWV) of an isomer mixture of C78 [23]. At that time we observed what appeared to be two sets of two oxidation peaks eadi, one set being approximately four times as intense... 

Distortions of dc polarographic waves for SCOC appeared at concentrations close to 1x10 M. For 2x10 M Cys the distinct distortions were evident for drop times longer than 2 seconds. Similar distortions for PrThz appeared already.at 1 s drop time (Fig.l). On the other hand, at the same Cys concentration, well developed curves were obtained in all pulse voltammetric techniques (Fig.2). The techniques studied were normal pulse, differential pulse and the fast square wave voltammetry (oswv) according to Osteryoungs. Pulse width dependence of normal pulse voltammetric waves confirmed their diffusional character and forward and reverse current curves in square wave voltammetry indicated reversibility of the oxidation process aiding in the increased sensitivity of this technique. 

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