Semitransparent polymer solar cells with 12.37% efficiency and 18.6% average visible transmittance

A series of opaque and semitransparent polymer solar cells (PSCs) were fabricated with PM6:Y6 as active layers, and 100 nm Al or 1 nm Au/(20, 15, 10 nm) Ag layer as electrode, respectively. The power conversion efficiency (PCE) of opaque PSCs arrives to 15.83% based on the optimized active layer with a thickness of 100 nm, resulting from the well-balanced photon harvesting and charge collection. Meanwhile, the 100 nm PM6:Y6 blend film exhibits a 50.5% average visible transmittance (AVT), which has great potential in preparing efficient semitransparent PSCs. The semitransparent electrodes were fabricated with 1 nm Au and different thick Ag layers, exhibiting a relatively high transmittance in visible light range and relatively low transmittance in near infrared range. The PCE and AVT of the semitransparent PSCs can be adjusted from 14.20% to 12.37% and from 8.9% to 18.6% along with Ag layer thickness decreasing from 20 to 10 nm, respectively, which are impressive values among the reported semitransparent PSCs. (C) 2019 Science China Press. Published by Elsevier B.V. and Science China Press. All rights reserved.