High efficiency and high open-circuit voltage (V-OC) ITO/boron subphthalocyanine chloride (SubPc)/C-60/bathocuproine/Al organic photovoltaic devices were fabricated in this study. Molecular packing was adjusted by controlling the deposition rate of SubPc, thus influencing the energy level of SubPc, which not only increased the energy level difference from the LUMO level of C-60 to the HOMO level of SubPc, but also reduced the energy barrier between the ITO/SubPc interface and diminished the accumulation and recombination of holes in SubPc, resulting in considerable improvement in both the V-OC (1.02 V) and fill factor (65.37%) of the device, and a 3.96% final efficiency of the device. (C) 2012 Elsevier B.V. All rights reserved.