Fig. 1

Molecular structures, properties and photovoltaic performance. a ZR1, Y6, IDIC-4Cl molecular structures. b Normalized UV–vis absorption spectra of ZR1, Y6, IDIC-4Cl in solution and thin films. c Energy diagrams of ZR1, Y6, IDIC-4Cl. d Optimized J–V curves for conventional devices. e EQE corresponding to devices in d.