Direct 3D printing of molten metal electrodes for perovskite solar cells

Owing to the solution-processability Perovskite solar cells (PSCs) are advancing rapidly in the field of emerging technologies. Layers forming the PSC can be easily printed or coated, the back electrode relies on metals such as gold, silver, aluminum, or copper, deposited via vacuum-based physical deposition, emphasizing the need for printed electrode alternative. This work demonstrates a novel additive manufacturing of printed molten metal electrodes (PME) utilizing StarJet technology. Bulk 57Bi-42Sn-1Ag alloy was printed by jetting directly onto PSC substrates. With this inexpensive and effective electrode material and deposition process, the PSCs achieved power conversion efficiency (PCE) ~11% under STC (1 sun, 1000 W/m 2 AM 1.5). Stability tests revealed a T80 > 1000 h for PME-based cells under ISOS-D shelf life test. While lower in performance, the approach demonstrates strong potential for cost-effective, scalable PSC manufacturing and highlights pathways for further optimization.