The limit of energy conversion of excitonic photovoltaic cells working under white light illumination generated by phosphor-based LED is analysed using the modified Giebink approach. Particularly, the impact of the optical energy gap and energy loss associated with the excitons dissociation at the heterojunction interface on power conversion efficiency of the device are discussed. From the results of our study it follows that the optimal optical energy gap value of organic materials equals 1.87–1.91 eV for the cool light and 1.80–1.82 eV for the warm light. The value of maximum power efficiency reaches 50%, if the energy loss related to excitons dissociation at the interface ED/EA is smaller than 0.3 eV and it decreases up to 40%, if the energy loss reaches the value of 0.5 eV. The obtained results reveal the direction of further improvement of efficiency of organic photovoltaic solar cells for indoor applications.

使用改进的Giebink方法分析了在基于荧光粉的LED产生的白光照射下工作的激子光伏电池的能量转换极限。特别地，讨论了与异质结界面处的激子离解相关的光能隙和能量损失对器件的功率转换效率的影响。从我们的研究结果可以看出，有机材料的最佳光能隙值对于冷光等于1.87–1.91 eV，对于暖光等于1.80–1.82 eV。如果与ED / EA界面处的激子离解相关的能量损失小于0.3 eV，则最大功率效率的值达到50％，如果能量损失达到0.5 eV的值，则最大功率效率的值降低至40％。