High efficiency, fully inkjet printed organic solar cells with freedom of design
Abstract
The organic photovoltaics field is maturing and reaching a technology readiness level where the focus is on developing large scale fabrication methods. In this light, fully inkjet printed organic solar cells were demonstrated. Inkjet printing allows direct patterning of all the layers, including the electrodes, offering full freedom of design without the use of masks or structuring by hardware. The semitransparent front and back electrodes consist of PEDOT:PSS and conductive Ag fingers, avoiding the use of ITO. The inkjet printing of six functional layer demonstrated minimal losses in performance as compared to the lab-scale standard, spin coated devices. All-inkjet printed large area (>1 cm2) organic solar cells with power conversion efficiency of 4.1% deposited from environmentally friendly solvents in an air atmosphere are demonstrated for the first time. Organic solar cells were fabricated using industrial scale (512 nozzles) printheads, compatible with R2R technology. To prove the great advantage of inkjet printing as a digital technology allowing freedom of forms and designs, large area organic solar cells with different artistic shapes were demonstrated. Reported results confirm that inkjet printing has high potential for the processing of OPV, allowing quick changes in design as well as the materials.