Rheological Optimization and Stability Study of Silver Nano-Ink for InkJet Printing of Solar Electrodes Using Industrial Printhead

摘要

We have demonstrated the capability of printing silver electrodes for solar cells having line width below 100 μm using inkjet printing. To achieve this, we have produced silver nanoparticles using the polyol synthesis and have tailored the ink formulation by choosing a solvent mixture to meet the rheological requirements of industrial printheads. A solvent mixture that can suspend the ligand capped silver nanoparticle was developed while maintaining the necessary rheology. A desktop R&D printer, the LP50 developed by Pix-Dro, has been used for the jetting optimization for the printhead used here. Statistical analysis of the jetting process was conducted using printer integrated software. Typical printing parameters such as greyscale, DPI variation and substrate heating were optimized to achieve high print quality. Tests of the dispersion showed that there was no sedimentation for more than a month. Solar collector network prototypes were successfully printed on silicon and ITO substrates.