Annealing-free alcohol-processable MoOX anode interlayer enables efficient light utilization in organic photovoltaics

Molybdenum oxide (MoOX) is a commonly used hole extraction material in organic photovoltaics. The MoOX interlayer is deposited typically via thermal evaporation in vacuum. To meet the need for roll to-roll manufacturing, solution processing of MoOX without post-annealing treatment is essential. Herein, we demonstrate an effective approach to produce annealing-free, alcohol-processable MoOX anode interlayers, namely S-MoOX, by utilizing the bis(catecholato) diboron (B(2)Cat(2)) molecule to modify the surface oxygen sites in MoOX. The formation of surface diboron-oxygen complex enables the alcohol solubility of S-MoOX. An enhanced light utilization is realized in the S-MoOX-based organic photovoltaics. This affords a superior short-circuit current density (J(SC)) close to 26 mA cm(-2) and ultimately a high power-conversion efficiency (PCE) of 15.2% in the representative PM6:Y6 based inverted OPVs, which is one of the highest values in the inverted OPVs using an as-cast S-MoOX anode interlayer. (C) 2021 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by ELSEVIER B.V. and Science Press. All rights reserved.

Automated summary

This study demonstrates an effective approach to produce annealing-free, alcohol-processable MoOX anode interlayers, namely S-MoOX, by modifying the surface oxygen sites in MoOX with the B(2)Cat(2) molecule. S-MoOX enhances light utilization and achieves superior performance in organic photovoltaics, with a high power-conversion efficiency of 15.2%.