Three dibenzothiophene-S,S-dioxide-based alternating copolymers were synthesized by facile Suzuki polymerization for visible light-responsive hydrogen production from water (> 420 nm). Without addition of any cocatalyst, FluPh2-SO showed a photocatalytic efficiency of 3.48 mmol h g- , while a larger hydrogen evolution rate (HER) of 4.74 mmol h g was achieved for Py-SO, which was ascribed to the improved coplanarity of the polymer that facilitated both intermolecular packing and charge transport. To minimize the possible steric hindrance of FluPh2-SO by replacing 9,9'-diphenylfluorene with fluorene, Flu-SO exhibited a more red-shifted absorption than FluPh2-SO and yielded the highest HER of 5.04 mmol h g . This work highlights the potential of dibenzothiophene-S,S-dioxide as a versatile building block and the rational design strategy for achieving high photocatalytic efficiency.

Owing to efficient singlet oxygen ( 1 O 2 ) generation in aggregate state, photosensitizers (PSs) with aggregation-induced emission (AIE) have attracted much research interests in photodynamic therapy (PDT). In addition to high 1 O 2 generation efficiency, strong molar absorption in longwavelength range and near-infrared (NIR) emission are also highly desirable, but difficult to achieve for AIE PSs since the twisted structures in AIE moieties usually lead to absorption and emission in short-wavelength range. In this contribution, through acceptor engineering, a new AIE PS of TBT is designed to show aggregation-induced NIR emission centered at 810 nm, broad absorption in the range between 300 and 700 nm with a large molar absorption coefficient and a high 1 O 2 generation efficiency under white light irradiation. Further, donor engineering by attaching two branched flexible chains to TBT yielded TBTC8, which circumvented the strong intermolecular interactions of TBT in nanoparticles (NPs), yielding TBTC8 NPs with optimized overall performance in 1 O 2 generation, absorption, and emission. Subsequent PDT results in both in vitro and in vivo studies indicate that TBTC8 NPs are promising candidates in practical application.The ORCID identification number(s) for the author(s) of this article can be found under https://doi.org/10.1002/adfm.201901791.(ROS) to kill cancer cells under light irradiation, has drawn widespread research interests owing to its good spatiotemporal precision, precise controllability, and noninvasiveness, etc. [1] Among which, the process that using emissive PSs as the key agents to find out the tumor site first and then realize PDT has been recognized as cost-effective and time-saving due to the integration of both diagnosis and treatment in one molecule. [2] To achieve effective PDT, smart design of PSs is of essential significance. Ideal properties of PSs include efficient 1 O 2 generation ability for cancer cell ablation, near-infrared (NIR) emission for imaging, strong absorption in long wavelength for easy excitation and good penetration depth, negligible dark toxicity for minimal side effects, and good photostability for continuous light irradiation. [3] Boron-dipyrromethene (BODIPY) derivatives, [4] metal complexes, [5] cyanine derivatives, [6] and porphyrin or chlorin derivatives, [7] are some typical traditional PSs. Heavy atoms are usually used to improve the 1 O 2 generation efficiency of BODIPY derivatives and metal complexes, which usually exhibit nontrivial dark toxicity with weak fluorescence. [4,5] Cyanine-type PSs are famous for their large absorbance in long-wavelength range with bright NIR emission over 800 nm. However, their poor 1 O 2 production capability and low photostability limited their practical application. [6] Porphyrin and chlorin derivatives usually show good 1 O 2 generation, but their light-absorbing capacity in long-wavelength range is generally rather poor, and their emission peaks are relatively blue as compared to those of cyanine-type PSs. [7] Several ...

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Tumor accumulation and intratumoral singlet oxygen (1O2) generation efficiency of photosensitizers (PSs) are two essential factors that determine their photodynamic therapy (PDT) efficacies. How to maximize the PS performance at the tumor site is of great research interest. Herein, we report a metal–organic framework (ZIF-8, ZIF = zeolitic imidazolate framework) assisted in vivo self-assembly nanoplatform, ZIF-8-PMMA-S-S-mPEG, as an effective tool for organic PS payloads to achieve efficient PDT. Using an organic PS with aggregation-induced emission as an example, under intratumoral bioreduction, PS-loaded ZIF-8-PMMA-S-S-mPEG (PS@ZIF-8-PMMA-S-S-mPEG) was self-assembled into large ordered hydrophobic clusters, which greatly enhance tumor retention and accumulation of the PS. Moreover, hydrophobic ZIF-8 assemblies greatly isolate the loaded PSs from water and improve O2 transport for the PSs to effectively produce 1O2 inside tumors under light irradiation. The organic PS is therefore endowed with optimal tumor accumulation and intratumoral 1O2 production, demonstrating the effectiveness of the developed self-assembly strategy in PDT application.

Conjugated polymer‐based photocatalysts have shown great potential in H2 production via water splitting, but an intrinsic drawback of conventional hydrophobic polymer photocatalysts is their poor wettability and relatively large particle size in aqueous media, which is favorable for charge recombination with limited interfacial reaction efficiency. Herein, a well‐dispersed organic water reduction system using cationic conjugated polyelectrolyte as the photocatalyst has been reported for the first time. In comparison to a model polymer (PFBT) bearing the same conjugated backbone, the polyelectrolyte exhibits significantly enhanced photocatalytic efficiency due to the extended light absorption and improved charge separation of the polymer aggregates.