Facile solution-processed molybdenum oxide as hole transporting material for efficient organic solar cell

摘要

The large energy barrier in hole extraction still remains a great challenge in developing hole transporting layer (HTL) materials for organic solar cells (OSCs).Thus,solution-processed HTL materials with excellent hole collection ability and good compatibility with large-area processing technique are strongly desired for OSCs.Herein,we developed a cost-effective and solution-processed MoO_(3)HTL for efficient OSCs.By adding a small amount of glucose as reducing reagent into the ammonium molybdate precursor solution,a deeply n-doped MoO_(3),namely G:Mo,was prepared through the sol–gel method.Compared to pristine MoO_(3),the conductivity of G:Mo was enhanced by two orders of magnitude,which greatly improved the hole collection ability of the HTL.OSCs with G:Mo can exhibit comparable PCE to the PEDOT:PSS device.Using PBDB-TF:BTP-eC9 as the active layer,a PCE of 17.1%is obtained for the device,which is the highest PCE value for OSC using a solution-processed MoO_(3)HTL.More importantly,G:Mo is well compatible with the blade-coating processing.The OSC using a blade-coated G:Mo showed almost no PCE loss as compared to the device with spin-coated G:Mo HTL.The results from this work indicate that G:Mo is a promising HTL material for the practical production of OSCs.