A Facile Solution-Processed Light Manipulation Structure for Organic Solar Cells

Light manipulation strategy plays a critical role in increasing the light harvesting of organic solar cells (OSCs). However, the incorporation of light manipulation structures in OSCs is usually hindered by complex lithography-based techniques. Herein, a facile and solution-processed structured ZnO film is proposed, consisting of ZnO colloidal spheres (CS) embedded in ZnO nanoparticles for broadband light scattering and antireflection in OSCs. By combining monodisperse ZnO CS (m-ZnO) as an electron collection layer and polydisperse ZnO CS (p-ZnO) as an antireflection layer, single-junction OSCs yield a substantial increase in photocurrent and power conversion efficiency by 14.63% compared to the reference cell with a flat structure. The experimental and theoretical characterizations ascribe the performance enhancement to the enhanced absorption due to a synergetic interplay of p-ZnO-induced antireflection and surface plasmonic scattering excited by corrugated metal electrode. It is anticipated that this light manipulation method represents a facile yet cost-effective route to achieving high-efficiency OSCs for commercially viable photovoltaic applications.