STAR Poster

Cesium Lead Iodide PerovskitesDrexel University, Chemical and Biological Engineering

Huilin Kuang, Dr. Aaron Fafarman

References

Introduction

Methods

Data/Results

Conclusion

Future Work

• Optimize electron transport in the film byincreasing the size of crystal grains andtheir connectivity

• Quantify the known metastability of thedesired black, perovskite phase

• Annealing at 350˚C the material changesfrom nonfunctional, yellow phase andcrystallizes into a black, polycrystalline,conductive phase

• Cesium lead iodide black phase containsconductive grains, but exposure toenvironment and high temperatures makesit susceptible to phase change into yellowphase

• Changing solvent made no significant impact on grain size

• Cesium lead iodide is best spin coated at 1000 RPM unheated

• Cesium lead iodide changes phases at 150˚C

S. Dastidar et al., "High chloride Dopinglevels stabilize the Perovskite phase ofCesium lead iodide,” Nano Letters, vol.16, no. 6, pp. 3563–3570, May 2016.

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PhaseChangeFromIncreasingTemperature

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CsPbI3DifferentSpinSpeedandTemperatureZoom

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Future work includes incorporating cesiumlead chloride into the films. Chloridestabilizes the iodide and allows for betterconductivity. The method of incorporationwould be by synthesizing both CsPb I"and CsPb Cl" nanocrystals and fusingthem together.