Room temperature ionic liquids (RTILs) were used in electrochemical polymerization and in doping studies (oxidation and reduction) of poly(para-phenylene) (PPP). Cyclic voltammetry was used simultaneously with Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) spectroscopy. Electropolymerization and doping of PPP were done by potential scanning in acetonitrile (ACN + 0.1 M TBAPF(6)), 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM][PF6]) and butylmethylpyrrolidinium bis (trifluoromethylsulfonyl) imide ([BMP][Tf2N]). The cyclic voltammograms recorded during polymerization of the PPP film indicate that the best film growth was achieved in [BMIM][PF6]. The films made in [BMP][Tf2N] were more stable than films made in ACN (0.1 M TBAPF(6)). Results from p-doping studies show that doping can be made at higher potentials in RTILs than in ACN (0.1 M TBAPF(6)). It was also found that n-doping can be performed in RTILs at higher negative potentials (-2.2V) than in ACN (0.1 M TBAPF(6)) (-1.8V). The best n-doping response was achieved in [BMP][Tf2N]. Also, n-doping in [BMIM][PF6] was better than in ACN (0.1 M TBAPF(6)). The in situ ATR-FTIR spectroscopy was used to study p- and n-doping of PPP films. During both p- and n-doping the spectra indicated formation of infrared active vibration bands (IRAV) in the wavenumber region 1600-800 cm(-1). The obtained IRAV bands correlate to the theoretical modes calculated by Zerbi and co-workers according to the effective conjugation coordinate theory (ECC). All these results indicate that RTILs are good solvents in spectroscopic and electrochemical studies of conducting polymers. (C) 2009 Elsevier Ltd. All rights reserved.