Medium-Bandgap Conjugated Polymer Donors for Organic Photovoltaics.

Recently, an increasing number of researchers have begun to focus on developing nonfullerene acceptors, so it is very important to synthesize new polymers that are compatible with nonfullerene acceptors. Besides, wide- or medium-bandgap polymer donors could be better to match narrow nonfullerene acceptors. The design of medium-bandgap (MBG) polymer donors and their application in organic photovoltaics (OPVs) play an important part in the improvement of OPV device performance. This review summarizes the photovoltaic performance of MBG polymers that have been reported during the last decade. Furthermore, their structure-property relationships and device performance are discussed. On the basis of analyzing many polymer structures, guidance toward the design of novel photovoltaic materials might be helpful to understand the basic OPV mechanism and the path towards commercialization.

Metallopolymer strategy to explore hypoxic active narrow-bandgap photosensitizers for effective cancer photodynamic therapy.

Practical photodynamic therapy calls for high-performance, less O2-dependent, long-wavelength-light-activated photosensitizers to suit the hypoxic tumor microenvironment. Iridium-based photosensitizers exhibit excellent photocatalytic performance, but the in vivo applications are hindered by conventional O2-dependent Type-II photochemistry and poor absorption. Here we show a general metallopolymerization strategy for engineering iridium complexes exhibiting Type-I photochemistry and enhancing absorption intensity in the blue to near-infrared region. Reactive oxygen species generation of metallopolymer Ir-P1, where the iridium atom is covalently coupled to the polymer backbone, is over 80 times higher than that of its mother polymer without iridium under 680 nm irradiation. This strategy also works effectively when the iridium atom is directly included (Ir-P2) in the polymer backbones, exhibiting wide generality. The metallopolymer nanoparticles exhibiting efficient O2•- generation are conjugated with integrin αvß3 binding cRGD to achieve targeted photodynamic therapy.