danДоклады Национальной академии наук БеларусиDoklady of the National Academy of Sciences of Belarus1561-83232524-2431The Republican Unitary Enterprise Publishing House "Belaruskaya Navuka"dan-357Research ArticleФИЗИКАPHYSICSВНУТРЕННЕЕ ЭЛЕКТРИЧЕСКОЕ ПОЛЕ, ЗАХВАТЫВАЮЩИЕ ЭЛЕКТРОНЫ ПУСТОТЫ, МЕРТВЫЕ ЭЛЕКТРОНЫ И УВЕЛИЧЕНИЕ ЭФФЕКТИВНОСТИ ПОЛИМЕРНЫХ СОЛНЕЧНЫХ ЭЛЕМЕНТОВ ПРИ ФТОРИРОВАНИИINTERNAL ELECTRIC FIELD, ELECTRON-TRAPPING VOIDS, DEAD ELECTRONS, AND THE INCREASING OF THE EFFICIENCY OF POLYMER SOLAR CELLS WITH FLUORINATIONПАВЛОВИЧВ. С.PAVLOVICHV. S.u.s.paulovich@tut.byВоенная академия БеларусиMilitary Academy of Belarus2016031120166057682Copyright © ПАВЛОВИЧ В.С., 20162016ПАВЛОВИЧ В.С.PAVLOVICH V.S.Данная работа распространяется под лицензией Creative Commons Attribution 4.0.This work is licensed under a Creative Commons Attribution 4.0 License.https://doklady.belnauka.by/jour/article/view/357

Предложена модель, позволяющая понять природу электронных ловушек в π-сопряженных полимерах, которые используются в фотоэлектрических устройствах. Предполагается, что пустоты со свободными полостями в полярном π-сопряженном полимере проявляют электроноакцепторные свойства и заполняются электронами, которые названы здесь «мертвыми» электронами, так как они удерживаются статическим случайным внутренним электрическим полем и не направляются к катоду с помощью внешнего напряжения. В результате, захваченные пустотами мертвые электроны непригодны для использования во внешней цепи органических солнечных элементов. Обосновано, что диссоциация экситонов на поверхности пустот, захват электронов пустотами при дрейфе к катоду, появление мертвых электронов и их негеминальная рекомбинация являются главными препятствиями при создании высокоэффективных полимерных солнечных элементов. Модель мертвых электронов позволяет объяснить увеличение эффективности преобразования энергии солнечных элементов, вызванное фторированием полимера, изменением боковых цепей полимера и наполнением ловушек добавками растворителей. Некоторые характеристики гибридных P3HT:CdSe солнечных элементов также анализируются с помощью этой модели. 

We propose a model that allows an understanding of the nature of electron traps in π-onjugated polymers that are used in photovoltaic devices. It is assumed that the free-cavity voids in the polar π-conjugated polymer exhibit electron-accepting affinity and are filled with electrons, called  erein as ‘dead’ electrons because they are hold by a static random internal electric field and are not driven to the cathode by external built-in voltage. As a result, the dead electrons into electron-trapping voids are unsuitable for use in the external circuit of organic solar cells. As justified here, the exciton dissociation on the surfaces of voids, the capture of drift electrons by voids, the emerging of the dead electrons and their non-geminate recombination are the main obstacles to create highly efficient polymer solar cells. The model of dead electrons allows explaining the increase in the power conversion efficiency of solar cells caused by the polymer fluorination, side-chain polymer manipulation, and dopant-controlled trap-filling. Some characteristics of hybrid P3HT:CdSe solar cells are also analyzed with the help of this model.

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The authors declare that there are no conflicts of interest present.