Optimization Light Utilization Efficiency of Semitransparent Organic Solar Cells by Regulating Absorption Spectrum

Semitransparent organic solar cells (ST-OSCs) have garnered significantly more attention in recent years due to their enormous potential commercial value in various fields, including building-integrated photovoltaics (BIPVs), transportation, electronic equipment, and agriculture. However, the equilibrium between power conversion efficiency (PCE) and average visible transmittance (AVT) is a key factor hindering the further development of ST-OSCs. Here, PM6 and LB-BO were elaborately selected as the donor and acceptor, respectively, for preparation of ST-OSCs. Through the modulation of the donor-to-acceptor (D/A) ratio, transparency was effectively enhanced without seriously affecting the photovoltaic performances of the devices. The optimized device achieved a PCE of 12.30% and an AVT of 20.63% with a D/A ratio of 0.7:1.2, while light utilization efficiency (LUE) reached 2.54%. To further improve the LUE, the MoO3 layer was introduced as an antireflective coating, resulting in a PCE of 10.62% and an AVT of 24.63%, thereby yielding an LUE of 2.62%. This strategy offers an efficient, straightforward, and cost-effective method to simultaneously enhance the PCE and AVT of ST-OSCs.