1. Environmental Effects of Organometal Lead Halide Perovskites When Used in Solar Cells By Scott Bechler

2. Background With the growing energy crisis, research on solar technology has been expanding rapidly One break through has been Organometal Lead Halide Perovskites Efficiencies have grown from 6% to 19.3% in the last few years Current silicon solar technologies operate at 25% efficiency Perovskites can be manufactured with cheap materials and relatively low-tech lab

3. Organometal Lead Halide Perovskites Unstable– degrade quickly with contact to air or moisture How much lead is leached and how will it affect the environment?

4. Method (continued) Used two Environmental Protection Agency (EPA) methods to test the cells’ tendency to leach lead Synthetic Precipitation Leaching Procedure: pH=4.2 Acid Rain Toxicity Characteristics Leaching Procedure: pH=5.0 Landfill Conditions Rotated cells in bottles end-over-end for 18 hours

5. Method Received cells with various layers Epoxy Titanium Oxide Organic Layer Silver Perovskite Glass

6. Results Before Acid Rain Leach After Acid Rain Leach Perovskite Glass Full Cell

7. Results (Continued) Acid Rain % LeachedLandfill Conditions % Leached 10 57 5439 42 21 26 14 Not tested Not Tested Not tested

8. Results Before Acid Rain Leach After Acid Rain Leach Perovskite Glass Full Cell

9. Results (Continued) Acid Rain % LeachedLandfill Conditions % Leached 10 57 5439 42 21 26 14 Not tested Not Tested Not tested

10. Future Plans Knowing the total initial lead content Determine percent leached What do the lab results mean in terms of real environmental scenarios? Which layers are better at minimizing lead leaching?

11. Acknowledgements Thanks to Sarah Jane White, Satish Myneni, Jim Shine, Cody Schlenker, Matt, Becky