We present the synthesis and characterization of seven new organic co-poly-ynes P1–P7 incorporating the phenothiazine (PTZ) motif and evaluate their optoelectronic properties and performance in polymer light-emitting diodes and polymer solar cells (PLEDs/PSCs). The co-poly-ynes were obtained in moderate to high yields via Sonogashira coupling reactions and characterized using analytical, spectroscopic and electrochemical techniques and complementary quantum-chemical modelling. The materials show strong optical absorption in the visible region of the spectrum and most also show strong emission with quantum yields in the range of 13–41% relative to rhodamine 6G (R6G). PLED devices based on the co-poly-ynes were prepared and the most promising was measured to have a brightness of up to 1.10 × 104 cd m−2. PSCs based on donor materials incorporating some of the polymers were prepared and demonstrated power conversion efficiencies of up to 0.24%.
