title: In situ surface-enhanced Raman scattering and X-ray photoelectron spectroscopic investigation of coenzyme Q10 on silver electrode.
abstract: In this study, coenzyme Q(10) (CoQ(10)) has been investigated by in situ near-infrared Fourier transform surface-enhanced Raman scattering (NIR-FT-SERS) spectroelectrochemistry and angle-resolved X-ray photoelectron spectroscopy (AR-XPS) on silver surface. The surface adsorption behavior of the coenzyme Q(10) radical intermediate could be monitored by potential-dependent SERS technique. At the applied potential lower than -0.30 V vs. SCE, the radical intermediate CoQ(10)H˙ stands perpendicularly on the silver surface with both oxygen atoms of the aromatic ring and isoprenoid side chains. When the applied potential is more positive than -0.30 V vs. SCE or at open circuit potential, the quinone ring (benzene ring) of reduced form of coenzyme Q(10) (CoQ(10)H(2)) adopts a face-on surface configuration on the surface. The responsible mechanism for the potential-dependent SERS spectra is presented. Moreover, the adsorption conformation of CoQ(10) has been further confirmed by AR-XPS at the silver surface.
authors.affiliation: Key Laboratory for Advanced Materials & Department of Chemistry, East China University of Science and Technology, Shanghai, 200237, PR China.
authors.forename: Dan
authors.initials: D
authors.lastname: Li
authors.forename: Da-Wei
authors.initials: DW
authors.lastname: Li
authors.forename: John S
authors.initials: JS
authors.lastname: Fossey
authors.forename: Yi-Tao
authors.initials: YT
authors.lastname: Long
mesh_terms: D004566:Electrodes; D056951:Photoelectron Spectroscopy; D012834:Silver / Q000737:chemistry*; D013059:Spectrum Analysis, Raman; D013499:Surface Properties; D014451:Ubiquinone / Q000031:analogs & derivatives* / Q000737:chemistry; D014965:X-Rays
chemical_list: D014451:Ubiquinone; D012834:Silver; C024989:coenzyme Q10