利用不同阴极缓冲层来改善Pentacene/C_(60)太阳能电池的性能

Inserting various cathodic buffer layers to enhance the performance of Pentacene/C_(60) based organic solar cells

制备了结构为ITO/Pentacene/C60/Al的双层光伏电池器件,在C60/Al界面插入了常用的缓冲层材料bathocuproine(BCP)作为阴极缓冲层,通过优化BCP层的厚度来提高电池的性能并研究了阴极缓冲层的作用机理.实验发现,BCP厚度为10nm时器件的效率最高,为0.46.在此基础上,利用bathophenanthroline(Bphen)和3,4,9,10-Perylenetetracarb-oxylicdianhydride(PTCDA)材料取代BCP,分别研究了缓冲层材料电子迁移率以及光吸收特性对器件性能的影响.在使用电子迁移率比BCP高两个数量级的Bphen材料作为缓冲层后,电池效率提高到了0.56.而当使用在可见光区有较强光吸收的PTCDA材料作为缓冲层时,可以起到增加电池光吸收的作用,电池短路电流提高至5.97mA/cm2,效率达0.87.

Devices with the structure of ITO /Pentacene /C60 /Al were prepared.Then,in order to enhance the performance of these cells and study the mechanism of the cathodic buffer layer,bathocuproine（BCP） of different thickness were inserted between C60 and Al.When inserting 10 nm BCP,the power conversion effciency of the cell is as high as 0.46.On this basis,bathophenanthroline（Bphen） and 3,4,9,10-Perylenetetracarb-oxylicdianhydride（PTCDA） are used instead of BCP,so as to compare and discuss the effects on the performance of the solar cells caused by the electron mobility and optical absorption properties of the cathodic buffer layers.As the electron mobility of Bphen is two orders of magnitude higher than that of BCP,the efficiency of devices with Bphen as the buffer layer was improved to 0.56.Furthermore,the absorption spectrum of devices was obviously enhanced by inserting PTCDA material which has large absorption in visible light region,and the highest current density of such device was enhanced to 5.97 mA /cm2 and the efficiency was 0.87.