SBIR Phase I: Fabrication via Ultraviolet LED Irradiation to Realize Stabilized Perovskite Solar Cells with Efficiencies over 25%

The broader impact of this Small Business Innovation Research (SBIR) Phase I project is to greatly advance perovskite solar cells (PVSCs) in terms of efficiency, stability, and readiness for commercialization. The success of the proposed research and development (R&D) activities will ensure a smooth transition from the realization of concepts in Phase I to prototype development of PVSCs on flexible substrates through slot-die coating in SBIR Phase II. Our final products will be mass-produced through low-cost roll-to-roll (R2R) printing and satisfy the customer needs for additional and cheaper electricity. By integrating our high-performance fully flexible solar panels with freight trailers/reefers, freight-truck owners can significantly reduce the diesel fuel consumption (by 30%) and avoid idle run of diesel engine while the drivers are resting. When our products are attached to the military tents, sufficient electricity can be generated to meet electricity needs at forward operating bases (FOBs), thereby significantly relieving the demand for diesel fuel at remote locations and effectively limiting the casualties related to the fuel transportation. In addition to its technical and commercial contribution, this project will impact society by involving and educating the new generation on the PVSCs with a sub-award to The University of Alabama. The proposed project will clear the obstacles that currently preventing PVSCs from upscaling manufacture and commercialization. Metal oxides rather than organic materials as charge transport layers have been demonstrated to enhance both device performance and stability. However, high quality metal-oxide films require high thermal annealing temperatures and long annealing time, which will destroy both flexible substrates and perovskite absorber layer. Photonic irradiation will be employed to achieve rapid and layer-specific annealing for both metal-oxide hole transport layer (HTL) and metal-oxide electron transport layer (ETL) without damaging other layers in PVSCs. Moreover, the rapid layer-specific photonic annealing happens in seconds, which is fully compatible with the R2R printing. With compositional engineering, the perovskite absorber layer will also go through rapid photonic treatment. The resulted PVSCs will be able to achieve PCE over 25% with long-term stability and pave the way for large-scale manufacturing of PVSCs through high-speed printing. The proposed highly-selective photonic treatment for each stacking layer in HTL/Perovskite/ETL sandwich structure provides the solution to achieve stabilized PVSCs with efficiency over 25%. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.