Dual fluorescent and time-dependent two-dimensional molecular crystals (DFTD-2DMC) as the effective fluorescent probes for sensing trace water in THF

For the first time, we have synthesized the dual fluorescent and time-dependent 2-dimensional molecular crystals (DFTD-2DMCs) which is a novel type of pure organic molecule nanosheets that exhibit the features of distinctive optical characteristics (dual fluorescence) with the various structural confirmations while exploring the interaction of pentacene-quinone derivative (2P-1) with tetrahydrofuran (THF). A number of solvents with different polarities were investigated in order to check the feasibility to produce the DFTD-2DMCs. These DFTD-2DMCs are further employed as luminous water sensors with high sensitivity and varied luminescence centers due to their distinctive optical and structural features. The donor-accepter-donor type complexes 2DMC-1 and 2 with electron-rich phenyl groups display an intermolecular charge transfer (ICT) state and form aggregates when detecting trace water in THF. The luminescence is reduced after contact with water, allowing quantitative analysis to quantify the water amount. The DFTD-2DMCs' capacity as a highly sensitive water sensor in an organic solvent (THF) was first demonstrated in this study by the lowest LODs for THF with 2DMC-1 (0.05 %) and 2DMC-2 (0.01 %). This novel observation is a pioneering approach for opening a new type of sensor by using the DFTD-2DMC.