▎ 摘　　要

Chemical vapor-deposition-grown graphene covered with a polyelectrolyte layer has been studied using Raman spectroscopy and in situ Raman spectroelectrochemistry. The doping of graphene leads to a shift of the Fermi level, which is reflected in changes of Raman spectra. A change of the Raman shift of the G band as a function of the electrode potential has been analyzed in this study to evaluate the doping level of graphene. The frequency shift of the G mode suggested an extreme doping of graphene (up 10(14) charge carriers per cm(2)), without obvious damage of graphene. (C) 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim