1 research outputs found
Cesium Lead Halide Perovskites with Improved Stability for Tandem Solar Cells
A semiconductor that can be processed
on a large scale with a bandgap
around 1.8 eV could enable the manufacture of highly efficient low
cost double-junction solar cells on crystalline Si. Solution-processable
organic–inorganic halide perovskites have recently generated
considerable excitement as absorbers in single-junction solar cells,
and though it is possible to tune the bandgap of (CH<sub>3</sub>NH<sub>3</sub>)ÂPbÂ(Br<sub><i>x</i></sub>I<sub>1–<i>x</i></sub>)<sub>3</sub> between 2.3 and 1.6 eV by controlling
the halide concentration, optical instability due to photoinduced
phase segregation limits the voltage that can be extracted from compositions
with appropriate bandgaps for tandem applications. Moreover, these
materials have been shown to suffer from thermal degradation at temperatures
within the processing and operational window. By replacing the volatile
methylammonium cation with cesium, it is possible to synthesize a
mixed halide absorber material with improved optical and thermal stability,
a stabilized photoconversion efficiency of 6.5%, and a bandgap of
1.9 eV