High efficiency polymer solar cells via sequential inkjet-printing of PEDOT:PSS and P3HT:PCBM inks with additives

Highly efficient and cost-effective polymer solar cells (PSCs) based poly(3-hexylthiophene) (P3HT) and 1-(3-methoxycarbonyl)-propyl-1-phenyl-(6,6)C61 (PCBM) have been fabricated by inkjet-printing with various additives. All solution-processed layers in the solar cells—a poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) layer and a photoactive layer based on P3HT and PCBM with additives—were inkjet-printed. The device performance is strongly influenced by the addition of high boiling point additives in the photoactive ink with chlorobenzene (CB) solvent. The morphology, optoelectronic properties, and overall solar cell performance of the devices were dramatically affected by additives, such as 1,8 octanedithiol (ODT), o-dichlorobenzene (ODCB) and chloronaphthalene (Cl-naph). A device fabricated from ink formulated with ODT exhibited the best overall performance with power conversion efficiency (PCE) of 3.71%.