title: pH-responsive luminescent properties of Ag@PPy nanoparticles.
abstract: We measure the emission spectra and quantum yields of Ag@PPy nanoparticles with different volume ratios of Ag core and PPy shell, and ascribe the emission peaks around 460 and 520 nm, respectively, to the S(1) → S(0) transition of the PPy molecule, and to the charge transfer between Ag and PPy, as well as the Ag plasmon. The two peaks shift with the changed doping level of the PPy shell, which can be elucidated by consideration of the energy levels of Ag and PPy. According to these results, we investigate the fast and reversible pH-sensing function of Ag@PPy nanoparticles on the basis of the doping effect on the interaction between the Ag core and the PPy shell.
authors.affiliation: Department of Polymer Science and Engineering, State Key Lab Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, China.
authors.forename: Sunjie
authors.initials: S
authors.lastname: Ye
authors.forename: Shujun
authors.initials: S
authors.lastname: Chen
authors.forename: Hongjuan
authors.initials: H
authors.lastname: Wang
authors.forename: Yun
authors.initials: Y
authors.lastname: Lu