Effect of the organic cation on the optical properties of Lead Iodine perovskites

César Tablero

doi:10.1016/j.solmat.2019.110022

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arXiv · 1907.12832

Effect of the organic cation on the optical properties of Lead Iodine perovskites

César Tablero

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Abstract

The effect of 14 organic cations on the optical properties of the lead iodine perovskite is analyzed. The electronic and optical properties are obtained using first principles. The absorption coefficients are split into inter-atomic species components in order to quantify all of the contributions. For energies close to the bandgaps, the main contribution is from the Pb-Pb intra-species transitions. For higher energy this contribution is still important in addition to I-I and Pb-I contributions, and to the 3 and 4 species term. Almost all absorption properties are qualitatively similar. Furthermore, this absorption coefficient splitting also allows the optical characteristics that the substitution of Pb by another element should satisfy to be identified in order to reduce the toxicity because of Pb while maintaining a high absorption capacity.

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César Tablero. 2019-07-30. Effect of the organic cation on the optical properties of Lead Iodine perovskites. https://doi.org/10.1016/j.solmat.2019.110022

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