%0 Journal Article %1 doi:10.1021/acsenergylett.7b00059 %A Correa Baena, Juan-Pablo %A Turren-Cruz, Silver-Hamill %A Tress, Wolfgang %A Hagfeldt, Anders %A Aranda, Clara %A Shooshtari, Leyla %A Bisquert, Juan %A Guerrero, Antonio %D 0 %J ACS Energy Letters %K perovskites reombination surface %N ja %P null %R 10.1021/acsenergylett.7b00059 %T Changes from Bulk to Surface Recombination Mechanisms Between Pristine and Cycled Perovskite Solar Cells %U http://dx.doi.org/10.1021/acsenergylett.7b00059 %V 0 %X Several aspects on the photophysical characterization of lead halide hybrid organic-inorganic perovskite solar cells still remain unsolved. It has been observed that ionic transport and polarization of the interfaces cause very slow changes that interfere transient measurements with effects that cannot be separated from recombination kinetics. Here we establish a protocol of initial measurement of the solar cell that provides information on recombination characteristics prior to applying any voltage cycling. The photovoltaic device is measured by several methods: photovoltage vs. light intensity, open circuit voltage decay (OCVD) and impedance spectroscopy (IS), whilst minimizing the exposure to external voltage stimulus to avoid ionic migration to the contacts. Results are independently confirmed by the analysis of samples with interdigitated electrodes. We show that the high efficiency perovskite solar cells behave very closely to a bulk recombination ideal photovoltaic model. However, when voltage is scanned to determine current-density voltage curves and Impedance Spectroscopy at fixed illumination intensity, the cell undergoes a significant change, which we attribute to a dominance of recombination at contacts that have been modified by ionic polarization. Our method provides an effective approach to determine quantitatively the rather significant changes that occur to perovskite solar cells during standard measurements such as current-voltage curves.

@article{doi:10.1021/acsenergylett.7b00059, abstract = { Several aspects on the photophysical characterization of lead halide hybrid organic-inorganic perovskite solar cells still remain unsolved. It has been observed that ionic transport and polarization of the interfaces cause very slow changes that interfere transient measurements with effects that cannot be separated from recombination kinetics. Here we establish a protocol of initial measurement of the solar cell that provides information on recombination characteristics prior to applying any voltage cycling. The photovoltaic device is measured by several methods: photovoltage vs. light intensity, open circuit voltage decay (OCVD) and impedance spectroscopy (IS), whilst minimizing the exposure to external voltage stimulus to avoid ionic migration to the contacts. Results are independently confirmed by the analysis of samples with interdigitated electrodes. We show that the high efficiency perovskite solar cells behave very closely to a bulk recombination ideal photovoltaic model. However, when voltage is scanned to determine current-density voltage curves and Impedance Spectroscopy at fixed illumination intensity, the cell undergoes a significant change, which we attribute to a dominance of recombination at contacts that have been modified by ionic polarization. Our method provides an effective approach to determine quantitatively the rather significant changes that occur to perovskite solar cells during standard measurements such as current-voltage curves. }, added-at = {2017-02-20T09:47:18.000+0100}, author = {Correa Baena, Juan-Pablo and Turren-Cruz, Silver-Hamill and Tress, Wolfgang and Hagfeldt, Anders and Aranda, Clara and Shooshtari, Leyla and Bisquert, Juan and Guerrero, Antonio}, biburl = {https://www.bibsonomy.org/bibtex/20e82432af43525150534603015a5dc3d/fabianopkm}, doi = {10.1021/acsenergylett.7b00059}, eprint = {http://dx.doi.org/10.1021/acsenergylett.7b00059}, interhash = {704054cb3d687bc7ade18f7697843aef}, intrahash = {0e82432af43525150534603015a5dc3d}, journal = {ACS Energy Letters}, keywords = {perovskites reombination surface}, number = {ja}, pages = {null}, timestamp = {2017-02-20T09:47:18.000+0100}, title = {Changes from Bulk to Surface Recombination Mechanisms Between Pristine and Cycled Perovskite Solar Cells}, url = {http://dx.doi.org/10.1021/acsenergylett.7b00059}, volume = 0, year = 0 }