Enhanced photocatalytic activity and photoresponse of poly(3,4-ethylenedioxythiophene) nanofibers decorated with gold nanoparticle under visible light

Conducting polymer nanostructures has been recognized as photocatlysts, a promising breakthrough in photo catalysis and other energy conversion application, such as fuel cell and battery in the near future. An efficient light harvesting hybrid nanostructures based on Poly(3,4-ethylenedioxythiophene) (PEDOT) nanofibers and gold nanoparticles (Au NPs) was prepared successfully via a one pot colloidal synthetic route. The plasmonic Au NPs (similar to 6 nm) are synergistically integrated on the conductive polymer nanofibers as evident from microscopic techniques. The Au/Ppy nanohybrids (NHs) demonstrate superior photocatalytic activity for organic pollutant degradation under visible light irradiation which is similar to 5.6 times higher than bare polymer (kinetic constant, over 46 times higher than the traditional Au/TiO2 catalyst). The photoinduced electron transfer from PEDOT nanofibers to Au NPs at the hybrid interface may occurred via a systematic extension of conjugation from polymeric moiety due to the closer proximity of the Au NPs which enhance the charge separation. The high-coverage of Au NPs deposition on the PEDOT nanofibers further allows surface-enhanced Raman scattering to detect the analyte molecules (Dye molecules such as Rhodamine B, Methyl orange) at a concentration of 10(-8) M with an enhancement factor of 10(4). Moreover, Au/PEDOT NHs demonstrated photoelectrochemical activity with the photo current density up to 11.2 mA cm(-2), which is 65% higher than bare PEDOT under similar reaction condition. Hence, Au/PEDOT NHs can be utilize for various applications such as photocatalytic degradation of organic pollutants and as SERS substrate for simultaneous detection of the analyte molecules and water splitting