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The diverse nature of organic precursors offers a versatile platform for precisely tailoring the electronic properties of semiconducting polymers. In this study, three fully conjugated sp2 carbon‐linked polymers have been designed and synthesized for photocatalytic hydrogen evolution under visible‐light illumination, by copolymerizing different C3‐symmetric aromatic aldehydes as knots with the 1,4‐phenylene diacetonitrile (PDAN) linker through a C=C condensation reaction. The hydrogen evolution (HER) is achieved at a maximum rate of 30.2 mmol g−1 h−1 over a polymer based on 2,4,6‐triphenyl‐1,3,5‐triazine units linked by cyano‐substituted phenylene, with an apparent quantum yield (AQY) of 7.20 % at 420 nm. Increasing the degree of conjugation and planarity not only extends visible‐light absorption, but also stabilizes the fully conjugated sp2‐carbon‐linked donor–acceptor (D–A) polymer. Incorporating additional electron‐withdrawing triazine units into the D–A polymer to form multiple electron donors and acceptors can greatly promote exciton separation and charge transfer, thus significantly enhancing the photocatalytic activity. [ABSTRACT FROM AUTHOR]

A metal–insulator–semiconductor (MIS) photosystem based on covalent organic framework (COF) semiconductors was designed for robust and efficient hydrogen evolution under visible‐light irradiation. A maximal H2 evolution rate of 8.42 mmol h−1 g−1 and a turnover frequency of 789.5 h−1 were achieved by using a MIS photosystem prepared by electrostatic self‐assembly of polyvinylpyrrolidone (PVP) insulator‐capped Pt nanoparticles (NPs) with the hydrophilic imine‐linked TP‐COFs having =C=O−H−N= hydrogen‐bonding groups. The hot π‐electrons in the photoexcited n‐type TP‐COF semiconductors can be efficiently extracted and tunneled to Pt NPs across an ultrathin PVP insulating layer to reduce protons to H2. Compared to the Schottky‐type counterparts, the COF‐based MIS photosystems give a 32‐fold‐enhanced carrier efficiency, attributed to the combined enhancement of photoexcitation rate, charge separation, and oxidation rate of holes accumulated in the valence band of the TP‐COF semiconductor. [ABSTRACT FROM AUTHOR]

The TiO2 film was coated on poly vinyl chloride (PVC) surface by dip‐coating process from TiO2–PVC–THF suspension. The morphology and crystal structure of the as‐synthesized samples were characterized by SEM and XRD. The photocatalytic properties were measured by the photodegradation reaction of RhB and the anti‐adhesion and anti‐bacteria for Escherichia coli. The results show that the resultant TiO2 film is well‐conglutinated on PVC surface and has the same crystal structure as the original TiO2 powder. The TiO2/PVC shows excellent photocatalytic activity for the degradation of aqueous RhB and the activity increases with increasing reaction time and tends toward stable after accumulative illumination for 11.5 h. The TiO2 film shows good bacterial anti‐adhesion activity following photo‐activation and sterilization property under UV irradiation. The E. coli can be killed completely after UV irradiation for 1.5 h. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 87B: 425–431, 2008 [ABSTRACT FROM AUTHOR]