title: New photophysical insights on effect of gold nanoparticles on the interaction between phthalocyanine and PC(70)BM in solution.
abstract: Photoinduced processes in phthalocyanine/functionalized gold nanoparticles (Pc/AuNps) have been investigated by spectroscopic measurements. It is observed while AuNps reduce the magnitude of binding constant for the non-covalent complexation between [6,6]-phenyl C71 butyric acid methyl ester (PC70BM) and H2-Pc by 15.8 times in comparison to PC70BM/ZnPc system in toluene, fluorescence of ZnPc is strongly quenched in presence of AuNp. Fluorescence lifetime determined by time-correlated single photon counting is also strongly reduced for ZnPc in presence of AuNp compared to H2-Pc. Symbolic enhancement in quantum yield of charge-separation associated with well-defined electrostatic interaction has been confirmed for PC70BM/ZnPc supramolecule in presence of AuNp. Transient absorption measurements establish that energy transfer mechanism is operative for both PC70BM/H2-Pc and PC70BM/ZnPc supramolecules in absence and presence of AuNp in toluene.
authors.affiliation: The University of Burdwan, Department of Chemistry, Golapbag, Burdwan 713 104, West Bengal, India.
authors.forename: Anamika
authors.initials: A
authors.lastname: Ray
authors.affiliation: Molecular Photochemistry Section, Radiation & Photochemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085, India.
authors.forename: Haridas
authors.initials: H
authors.lastname: Pal
authors.affiliation: National Centre for Ultrafast Processes, University of Madras, Taramani Campus, Chennai, India.
authors.forename: Vadivel
authors.initials: V
authors.lastname: Ramanan
authors.affiliation: The University of Burdwan, Department of Chemistry, Golapbag, Burdwan 713 104, West Bengal, India. Electronic address: sum_9974@rediffmail.com.
authors.forename: Sumanta
authors.initials: S
authors.lastname: Bhattacharya
keywords: Binding constant; Energy transfer; Gold nanoparticle; H(2)- and ZnPc; PC(70)BM