Study of small molecule organic solar cells performance based on boron subphthalocyanine chloride and C₆₀

The small molecule organic solar cells based on boron subphthalocyanine chloride (SubPc) and C₆₀ by varying the SubPc layer thickness from 3 nm to 21 nm were fabricated. The maximum power conversion efficiency (PCE) of 1.47% was obtained at the 9 nm SubPc layer under 100 mW/cm² AM1.5G illumination, which is attributed to reach the optimal balance between the light absorption efficiency and the carrier collection efficiency in the device. To increase the open-circuit voltage (Voc) of device, the molybdenum oxide (MoO₃) and poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) were inserted between the indium tin oxide and the SubPc layer, respectively. Finally, the Voc of device increased from 0.46 V to 1 V by using MoO₃ buffer layer, resulting in the fact that the PCE of device increased from 1.47% to 2.52%.