Fig. 2: Chemical structures of photoactive materials and the related physical properties.

a Chemical structures of D18, DTC8, and Six-IC. UV-vis absorption spectra of DTC8 and Six-IC in (b) solution state and (c) films. d Energy level distribution of D18, DTC8, and Six-IC. DMT results of (e) DTC8 and (f) Six-IC. g DSC curves of DTC8 and Six-IC (Solid lines and dashed lines represent the heating and cooling processes, respectively).