The article reports a straightforward strategy for the design and synthesis of highly luminescent conjugated mesoporous oligomers (CMOs) with an "aggregation-induced enhanced emission" (AIEE) feature through Wittig polymerization of a molecular rotor. Typical molecular rotors such as triphenylamine (TPA) and tetraphenylethene (TPE) as B2-, and A4-and A3type nodes have been used to construct AIEE-active CMOs, namely, CMO1 and CMO2. The quick dissipation of the excited photons is successfully controlled by the restriction of rotation of the phenyl units through the formation of a mesoporous network scaffold in a solid/thin film, which provides high quantum yields for the interlocked CMO system. Both the CMOs are sensitive and selective to the various nitroaromatic explosives, whereas CMO1 is more sensitive (K sv = 2.6 × 10 6 M −1 ) toward picric acid. The increased quenching constant for CMO1 is due to its increased quantum yield and high energy-transfer efficiency. The mechanism for sensing has been studied in detail. The larger pore size and pore density in the mesoporous network of CMO1 are found to be responsible for the greater extent of energy transfer from CMO1 to picric acid. Furthermore, CMO1 has been employed for low-cost filter-paper-based detection of a trace amount of nitroaromatic explosive materials.

Selective vapor-phase detection of dichloromethane (DCM) is a challenge, it being a well-known hazardous volatile organic solvent in trace amounts. With this in mind, we have developed an ‘Aggregation-induced Emission’ (AIE) active mono-cyclometalated iridium(III)-based (M1) probe molecule, which detects DCM sensitively and selectively in vapor phase with a response time < 30 s. It reveals a turn-on emission (non-emissive to intense yellow) on exposing DCM vapor directly to the solid M1. The recorded detection limit is 4.9 ppm for DCM vapor with pristine M1. The mechanism of DCM detection was explored. Moreover, the detection of DCM vapor by M1 was extended with a low-cost filter paper as the substrate. The DCM is weakly bound with the probe and can be removed with a mild treatment, so, notably, the probe can be reused.

It is highly demanding to develop fluorescent-based multi-stimuli responsive material. Herein, we reported an oligomeric network labeled P1, composed of heterocyclic triazine as π-electron acceptor (A) connected directly with π-electron...

The non-luminescent monomeric unit M1 transforms into intensely yellow emissive phosphorescent polymers upon polymerization, termed polymerization-induced phosphorescent emission (PIPE). A simple free radical polymerization method is employed for the polymer synthesis where the homopolymer (HP) exhibiting PIPE is generated from vinyl monomers (M1) via non-conjugated bond formation. High photo efficiency observed for the PIPE-active HP may have resulted from the possible intrachain and interchain interactions, among the repeating units. By using various monomer compositions, this synthetic technique provides copolymer and emission tuning. Integrating blue-emitting carbazole with the PIPE-active HP resulted in the white-light-emitting copolymer (CP4). This is the first report on PIPE-active-mediated white-light-emitting copolymer with CIE coordinates (0.25, 0.33). The resulting copolymer (CP4) showed a high quantum yield (33.7%) with a long excited-state lifetime (6.54 μs). PIPE-active phosphorescent-based whitelight-emissive polymeric materials could motivate the development of advanced materials for white-light-emitting diode devices.

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