Turning Green Chemistry into Green Energy: From Lab Ink to Industrial Slot-Die Coating
Slot-Die Coating Project with Solaveni
The Solar TAP collaboration between HZB, Humboldt University, and Solaveni has enabled a crucial step forward in sustainable photovoltaics: the creation of a non-toxic, water- and alcohol-based precursor ink suitable for slot-die coating perovskite absorber materials under ambient conditions.
The central innovation focuses on the use of a protic ionic liquid (methylammonium propionate, MAP) that makes it possible to dissolve perovskite precursors in eco-friendly solvents like water and alcohol, moving away from hazardous DMF-based formulations.
Thanks to Solar TAP, the research transitioned swiftly from lab innovation to industrial relevance, enabling Solaveni to directly access high-quality green materials and scalable deposition processes for future solar cell production.
Perovskite film generated with the “green coating method”.
Project details
Key Achievements
Through the collaboration fostered by Solar TAP, researchers at HZB and Humboldt University, together with Solaveni, successfully developed a novel green perovskite ink based on non-toxic solvents like water and alcohol, enabled by the protic ionic liquid MAP (methylammonium propionate).
This breakthrough formulation allowed for one-step slot-die coating of perovskite layers under ambient conditions, demonstrating stable film formation without the need for hazardous solvents like DMF or DMSO.
The green ink achieved solar cell efficiencies of up to 10%, marking a major advance in sustainable photovoltaics. Importantly, the ink showed excellent shelf stability and could be processed in regular air environments, making it attractive for scalable manufacturing.
Beyond the laboratory, this project represented a key translation of green chemistry into industrial practice, offering scalable production routes for future printed solar modules. The successful integration of material development and scalable processing validates Solar TAP’s model of accelerating technology transfer through targeted industry-academic collaboration.
Linking Science and Industry
Solar TAP brought together HZB’s cutting-edge material research and Solaveni’s industrial expertise.
Through an active collaboration and iterative testing, the partners co-developed a practical green ink formulation that aligns with manufacturing needs, dramatically shortening the time from lab discovery to industrial evaluation.
The focus on scalable slot-die coating ensures that the innovation is ready for pilot-scale production and beyond—bringing sustainable materials closer to commercial application.
Future Outlook
Building on this success, Solar TAP and Solaveni are working to extend green solvent use to more perovskite compositions evaluating other protic ionic liquids. We also expand activities towards metal oxide suspensions to enable fully slot-die coated solar cell stacks—a critical step for low-cost, sustainable hybrid electronics and photovoltaics.
Added Value
for the Industrial Partner
- Accelerated product development cycle through direct access to R&D.
- Demonstration of industrially relevant coating methods under real-world conditions
- New pathways for sustainable product lines in perovskite photovoltaics
for Research
- Accelerated product development cycle through direct access to R&D.
- Demonstration of industrially relevant coating methods under real-world conditions
- New pathways for sustainable product lines in perovskite photovoltaics
for Society
- Contribution to safer, greener solar manufacturing. Support for reducing hazardous waste in future energy technologies. Acceleration of the clean energy transition through sustainable innovation.
