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Bandgap engineering in donor–acceptor conjugated microporous polymers (CMPs) is a potential way to increase the solar‐energy harvesting towards photochemical water splitting. Here, the design and synthesis of a series of donor–acceptor CMPs [tetraphenylethylene (TPE) and 9‐fluorenone (F) as the donor and the acceptor, respectively], F0.1CMP, F0.5CMP, and F2.0CMP, are reported. These CMPs exhibited tunable bandgaps and photocatalytic hydrogen evolution from water. The donor–acceptor CMPs exhibited also intramolecular charge‐transfer (ICT) absorption in the visible region (λmax=480 nm) and their bandgap was finely tuned from 2.8 to 2.1 eV by increasing the 9‐fluorenone content. Interestingly, they also showed emissions in the 540–580 nm range assisted by the energy transfer from the other TPE segments (not involved in charge‐transfer interactions), as evidenced from fluorescence lifetime decay analysis. By increasing the 9‐fluorenone content the emission color of the polymer was also tuned from green to red. Photocatalytic activities of the donor–acceptor CMPs (F0.1CMP, F0.5CMP, and F2.0CMP) are greatly enhanced compared to the 9‐fluorenone free polymer (F0.0CMP), which is essentially due to improved visible‐light absorption and low bandgap of donor–acceptor CMPs. Among all the polymers F0.5CMP with an optimum bandgap (2.3 eV) showed the highest H2 evolution under visible‐light irradiation. Moreover, all polymers showed excellent dispersibility in organic solvents and easy coated on the solid substrates. Tuning the bandgap: A series of donor–acceptor conjugated microporous polymers with tunable bandgap, showing energy‐transfer‐assisted charge‐transfer emission, was exploited as efficient photocatalysts for hydrogen evolution. [ABSTRACT FROM AUTHOR]

We design a flexible, amphiphilic LMWG consisting of donor and acceptor π-chromophores which self-assembles into a hydrogel and an organogel with different nano-morphologies. Different mechanisms of self-assembly evolve charge transfer (CT) emission in the hydrogel and LMWG-based emission in the organogel. Moreover, the hydrogel-nanostructure with surface exposed amide groups is explored for catalyzing Knoevenagel condensation reaction. [ABSTRACT FROM AUTHOR]