LAUSR

Abstract Incorporation of a magnesium oxide (MgO) cathode buffer layer fabricated by a reaction of thermally-deposited magnesium with molybdenum oxide in semi-transparent vacuum-processed Schottky and solution-processed bulk heterojunction OSCs using gold as a cathode metal reduces the series resistance and reverse bias current density, thus preventing the reduction of the open-circuit voltages and fill factors. It is speculated that the high hole-blocking ability of MgO which possesses the deep-lying conduction band level is responsible for these results.