Time Resolved Spectroscopic Study of Photocurrent Generation of Phospholipid Assembled DSSN+

Abstract

Time-resolved spectroscopic study has attracted a significant amount of interest in the past several decades because it provides the essential information to fully understand photophysical properties of compounds in the excited state. We introduced time-resolved spectroscopic techniques such as femtosecond transient absorption and time-correlated single photon counting spectroscopy to study dynamics and the lifetime occurring in the excited state. To demonstrate the feasibility of these techniques, we applied to study about energy transfer in molecular photovoltaic devices. In this study, we implemented water-based artificial photovoltaic system using conjugated oligoelectrolytes and a dye. We used 4,4-bis(4-(N,N-bis(6-(N,N,N-trimethylammonium)hexyl) amino)-styryl)stilbene tetraiodide (DSSN+) as a donor and Nile red as an acceptor. DSSN+ and Nile red are intercalated into DMPC vesicle and we investigated the energy transfer from DSSN+ to Nile red using steady-state photoluminescence, time-correlated single photon counting and transient absorption techniques. In this vesicle system, the value of fluorescence resonance energy transfer (FRET) efficiency between the donor and the acceptor is considerable. Moreover, we studied the photocurrent generation in an optimized photovoltaic system.