Experimental results

A typical spectrum of 13CO derived from the decomposition of 13C-enriched methanol on PC platinum black is shown in Fig. 5(A). Fig. 5(B) shows the first electrochemical cycle after methanol decomposition, followed by rinsing, without circuit interruption. The voltammogram is used to determine surface coverage from the CO -> CO2 oxidation peak at around 400 mV (versus a Ag/AgCl reference electrode, in 1.0 M NaCl). Typical mini-cell NMR spectra for 13C- and 15N-labeled CN" on Pt black are shown in Fig. 6.

Using the electrochemical NMR cell, the potential dependence of the frequency shift for CO and CN on platinum black is currently being investigated. Data such as these will then be used as a basis for modeling how chemical shifts and electronic structure may be influenced by an applied electric field.

PPM ((ram TM$)

NMRE C*0 Vottammogram

PCPWkwm

NMRE C*0 Vottammogram

PCPWkwm

Fig. 5. (A) A typical 13CO-Pt black spectrum with a 0.0 V applied potential at 8.45, 13200 transients, S/N ratio = 14.0:1. (B) CV after NMR measurements, taken at 0.1 mV/s (see text).
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