%0 Journal Article %1 yang2017acoustic-optical %A Yang, Jianfeng %A Wen, Xiaoming %A Xia, Hongze %A Sheng, Rui %A Ma, Qingshan %A Kim, Jincheol %A Tapping, Patrick %A Harada, Takaaki %A Kee, Tak W. %A Huang, Fuzhi %A Cheng, Yi-Bing %A Green, Martin %A Ho-Baillie, Anita %A Huang, Shujuan %A Shrestha, Santosh %A Patterson, Robert %A Conibeer, Gavin %D 2017 %I Nature Publishing Group %J Nature Communications %K energy_harvesting perovskite upconversion %P 14120 %R 10.1038/ncomms14120 %T Acoustic-optical phonon up-conversion and hot-phonon bottleneck in lead-halide perovskites %U /brokenurl#http:https://dx.doi.org/10.1038/ncomms14120 %V 8 %X The hot-phonon bottleneck effect in lead-halide perovskites (APbX3) prolongs the cooling period of hot charge carriers, an effect that could be used in the next-generation photovoltaics devices. Using ultrafast optical characterization and first-principle calculations, four kinds of lead-halide perovskites (A=FA+/MA+/Cs+, X=I−/Br−) are compared in this study to reveal the carrier-phonon dynamics within. Here we show a stronger phonon bottleneck effect in hybrid perovskites than in their inorganic counterparts. Compared with the caesium-based system, a 10 times slower carrier-phonon relaxation rate is observed in FAPbI3. The up-conversion of low-energy phonons is proposed to be responsible for the bottleneck effect. The presence of organic cations introduces overlapping phonon branches and facilitates the up-transition of low-energy modes. The blocking of phonon propagation associated with an ultralow thermal conductivity of the material also increases the overall up-conversion efficiency. This result also suggests a new and general method for achieving long-lived hot carriers in materials.

@article{yang2017acoustic-optical, abstract = {The hot-phonon bottleneck effect in lead-halide perovskites (APbX3) prolongs the cooling period of hot charge carriers, an effect that could be used in the next-generation photovoltaics devices. Using ultrafast optical characterization and first-principle calculations, four kinds of lead-halide perovskites (A=FA+/MA+/Cs+, X=I−/Br−) are compared in this study to reveal the carrier-phonon dynamics within. Here we show a stronger phonon bottleneck effect in hybrid perovskites than in their inorganic counterparts. Compared with the caesium-based system, a 10 times slower carrier-phonon relaxation rate is observed in FAPbI3. The up-conversion of low-energy phonons is proposed to be responsible for the bottleneck effect. The presence of organic cations introduces overlapping phonon branches and facilitates the up-transition of low-energy modes. The blocking of phonon propagation associated with an ultralow thermal conductivity of the material also increases the overall up-conversion efficiency. This result also suggests a new and general method for achieving long-lived hot carriers in materials.}, added-at = {2017-02-16T13:55:09.000+0100}, author = {Yang, Jianfeng and Wen, Xiaoming and Xia, Hongze and Sheng, Rui and Ma, Qingshan and Kim, Jincheol and Tapping, Patrick and Harada, Takaaki and Kee, Tak W. and Huang, Fuzhi and Cheng, Yi-Bing and Green, Martin and Ho-Baillie, Anita and Huang, Shujuan and Shrestha, Santosh and Patterson, Robert and Conibeer, Gavin}, biburl = {https://www.bibsonomy.org/bibtex/2502669a64c0684419dcfe7559b9c7e6e/bretschneider_m}, doi = {10.1038/ncomms14120}, interhash = {bdd330d9c2fc87cd8b465fe58a363eeb}, intrahash = {502669a64c0684419dcfe7559b9c7e6e}, issn = {2041-1723}, journal = {Nature Communications}, keywords = {energy_harvesting perovskite upconversion}, month = {1}, pages = 14120, publisher = {Nature Publishing Group}, timestamp = {2017-02-16T13:55:09.000+0100}, title = {Acoustic-optical phonon up-conversion and hot-phonon bottleneck in lead-halide perovskites}, url = {/brokenurl#http:https://dx.doi.org/10.1038/ncomms14120}, volume = 8, year = 2017 }