Origin of the light intensity dependence of the short-circuit current of polymer/fullerene solar cells
Origin of the light intensity dependence of the short-circuit current of polymer/fullerene solar cells
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DOI：
10.1063/1.2130396
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发表时间：
2005-11-14
影响因子：
4
通讯作者：
Blom, PWM
中科院分区：
文献类型：
--
作者：
Koster, LJA;Mihailetchi, VD;Blom, PWM
聚合物/富勒烯基太阳能电池的一个典型特征是短路条件下的电流密度（J(sc)）与光强(I)不完全成线性比例。相反，幂律关系由J（sc）与I-alpha成正比，其中alpha的范围从0.85到1。在一些报道中，这种对统一性的偏离被推测是由双分子重组的发生引起的。我们证明了光电流在体异质结太阳能电池中的依赖性是由电子和空穴迁移率差异导致的器件中空间电荷的积累所控制的。我们已经在一个实验模型系统中验证了这一点，其中通过改变退火处理，迁移率差异可以从一个数量级调整到三个数量级。(C) 2005美国物理研究所。
A typical feature of polymer/fullerene based solar cells is that the current density under short-circuit conditions (J(sc)) does not scale exactly linearly with light intensity (I). Instead, a power law relationship is found given by J(sc)proportional to I-alpha, where alpha ranges from 0.85 to 1. In a number of reports this deviation from unity is speculated to arise from the occurrence of bimolecular recombination. We demonstrate that the dependence of the photocurrent in bulk heterojunction solar cells is governed by the build-up of space-charge in the device as a consequence of a difference in electron- and hole mobility. We have verified this for an experimental model system in which the mobility difference can be tuned from one to three orders of magnitude by changing the annealing treatment. (C) 2005 American Institute of Physics.