Ultrafast static and diffusion-controlled electron transfer at Ag₂₉ nanocluster/molecular acceptor interfaces

Abstract

Efficient absorption of visible light and a long-lived excited state lifetime of silver nanoclusters (Ag29 NCs) are integral properties for these new clusters to serve as light-harvesting materials. Upon optical excitation, electron injection at Ag29 NC/methyl viologen (MV(2+)) interfaces is very efficient and ultrafast. Interestingly, our femto- and nanosecond time-resolved results demonstrate clearly that both dynamic and static electron transfer mechanisms are involved in photoluminescence quenching of Ag29 NCs.

The tetrahedral structure and luminescence properties of Bi-metallic Pt1Ag28(SR)18(PPh3)4 nanocluster

“…21b,22b,35–37 As the crystal structures of Pt 1 Ag 24 and Pt 1 Ag 28 are different, it would be helpful to compare the excited state behavior between the homosilver Ag 25 and Ag 29 nanoclusters with their Pt doped counterparts, which have similar structures. 21a,22a,38 Table S3† lists the excited state lifetimes of Ag 25 and Ag 29 from the literature together with those of Pt 1 Ag 24 and Pt 1 Ag 28 obtained in this study. Both Ag 25 and Ag 29 have relatively low fluorescence (QYs < 1%).…”

Gold Doping of Silver Nanoclusters: A 26‐Fold Enhancement in the Luminescence Quantum Yield

“…This single long-lived component is attributed to al igand-to-metal charge trans- Angewandte Chemie Zuschriften fer. [19] Thel ong-lived nature of this excited state is also observed for other silver NCs. [20] Thef itting of the time profiles of Au-doped clusters shows two time components as presented in Table S1, unlike pure Ag 29 NCs,which show just as ingle dominant lifetime.T his implies an involvement of as omewhat different mechanism that causes PL enhancement in Au-doped NCs.Ascan be seen in Figure 3A,aclear enhancement in the long lifetime component was observed for 20 and 40 %A u-doped samples (612 AE 65 ns and 890 AE 71 ns,respectively).…”

Temperature responsive polymer brushes grafted from graphene oxide: an efficient fluorescent sensing platform for 2,4,6-trinitrophenol

“…48 If only one type of quenching mechanism is taking place, the quenching can be expressed by the Stern − Volmer equation: [48][49][50][51][52][53][54][55][56] Dynamic quenching happens when the excited fluorophore comes in contact with the quencher molecule, which facilitates non-radiative transition to the ground state and the process leads to the quenching of fluorescence intensity.…”

“…As shown in Fig.11, TNP solution shows two typical absorption bands at 365 nm and 251 nm. [51][52][53][54] Fig. Furthermore, the UV-vis absorption, excitation and emission spectra of the Alq 3 -containing block copolymer brush-GO hybrid were also measured in the absence and presence of TNP.…”