Fabrication and photoelectric properties of bio-inspired honeycomb film based on semiconducting polymer

Organic semiconducting materials have attracted significant attention for use in optoelectronic devices, as they can significantly improve device performance. Herein, a donor–acceptor conjugated polymer (poly(isoindigo-thiopheneylbenzothiadiazole, PID-TBT) was synthesized, which has strong and broad absorption in the visible region (400–800 nm). The band gap of PID-TBT is 1.65 eV. The PID-TBT honeycomb film with a porous structure was easily fabricated by the breath figure method. Compared with the smooth PID-TBT film, the honeycomb film shows significant enhancement in light capture capability and the efficiency of photoelectric conversion. The reflectance of the honeycomb film is reduced by 7% and the photocurrent is tenfold higher than that of the smooth film. Apart from designing new molecules by complex reactions, this work demonstrated that photoelectric conversion can be easily improved by introducing micro or nanostructures into devices.