Switching the Photoluminescence and Electrochemiluminescence of Liposoluble Porphyrin in Aqueous Phase by Molecular Regulation.

A facile molecular structure regulation strategy was exploited to potentially transform the aggregation-caused quenching (ACQ) chromophore of lipsoluble porphyrin to the aggregation-induced emission (AIE) active in aqueous phase. By peripheral decoration of 5-(4-aminophenyl)-10,15,20-triphenylporphyrin (ATPP) with inherent AIE active tetraphenylethene (TPE), a versatile AIEgenic porphyrin derivative (ATPP-TPE) was obtained, which greatly abolishes the detrimental π-π stacking and thus surmounts the notorious ACQ effect of ATPP in aqueous phase. The photoluminescence of ATPP-TPE is 4.5-fold stronger than ATPP at aggregation state. Moreover, an unequivocal aggregation induced electrochemiluminescence (AIECL) of ATPP-TPE was found seriously dependent on its aggregation property in aqueous solution with efficiency of 34%, which is 6 times higher than pure ATPP. The versatility of this molecular structure modulation strategy along with the ACQ-to-AIE transformation in this work provides direction to guide for applying liposoluble porphyrins in aqueous phase by designs of synthetic porphyrin AIEgens.