Photophysical properties of certain pyrene derivatives

The pyrene chromophore is an extensively investigated building material owing to its intriguing photophysical properties such as high molar absorption coefficient and long-lived singlet state. Furthermore, pyrene has myriad substitution sites for molecular engineering. As a result, many pyrene derivatives have been developed over the decades, and they have been used as potential candidates in a variety of emerging fields, including organic electronics, fluorescent molecular probes, sensors and solar cells.However, pyrene-based dye sensitized solar cells is less common. For instance, Song et al., reported a novel tetrahydropyrene-based D-π-A organic dye with a power conversion efficiency of 6.75%.Notably, Nagarajan et al., reported a phenothiazine conjugated pyrene derivatives with a maximum power conversion efficiency of 12%. Although the power conversion efficiencies of pyrene derivatives have been reported in the literature, no systematic work has been conducted to correlate the significance of excited state features with the photovoltaic properties of pyrene derivatives. For instance, the influence of anchoring groups, rigidspacer, aggregation behaviour, and so on.In fact, even minor changes in the dye's molecular structure can result in novel photophysical, electrochemical, and other properties. A series of pyrene derivatives were devised and developed to acquire a greater understanding of the structure-property relationship and correlate the device performance. UV-visible absorption, steady-state fluorescence, time-resolved fluorescence, and computational techniques have been utilized to examine the effect of various parameters on theground and excited state characteristics of pyrene derivatives