A Resonance Raman spectroscopic study on charge transfer enhancement in photosensitizers

The charge transfer (CT) properties of photosensitizers largely determine the photovoltaic performances dye sensitized solar cells (DSSCs). Thus, understanding CT is key to further improving DSSCs. We herein investigated underlying relationship between molecular structures and using resonance Raman (RR) spectroscopy density functional theory (DFT) calculations. RR combined with DFT calculations showed that presence a triple bond ( T-D1 , T-D2 T-D3 ) enhanced degree from donor acceptor. In addition, electron donating groups (EDGs) on increased donor. Moreover, analysis based harmonic oscillator model aromaticity revealed an EDG quinoidal character photosensitizer in excited state. Finally, it was found exhibited by each good agreement order DSSC performances.