Figure 8: Spectroelectrochemistry.

(a) UV-visible absorption spectral changes observed during the electrochemical oxidation of Py-1-SWNT by applying a potential from 0 to 1.0 V versus Ag/AgNO₃ in DMF. The absorption spectrum of Py-1-SWNT recorded in the absence of an applied potential is shown by the dotted black line. (b) Differential absorption (ΔA) spectra of Py-1-SWNT with respect to oxidation. The reference spectrum corresponds to the absorption spectrum recorded in the absence of an applied potential. (c) UV-visible absorption spectral changes observed during the electrochemical reduction of p-SWNT under an applied potential of –1.0 to –2.6 V versus Ag/AgNO₃ in DMF. The absorption spectrum of p-SWNT recorded in the absence of an applied potential is also shown by the dotted black line. (d) Differential absorption spectra of p-SWNT with respect to reduction. The reference spectrum corresponds to the absorption recorded in the absence of an applied potential. All measurements were conducted in DMF using Bu₄NPF₆ (20 mM) as an electrolyte.