A strategic buffer layer of polythiophene enhances the efficiency of bulk heterojunction solar cells.
We have developed polymer solar cells featuring a buffer layer of polythiophene (PT) sandwiched between the active layer and the poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) layer. We attribute the improvement in power conversion efficiency of these polymer solar cells, relative to that of those based on poly(3-hexylthiophene):[6,6]-phenyl-C(61)-butyric acid methyl ester (P3HT:PCBM), to a reduction in the degree of carrier recombination at the junction interface. Because the conductivity and the energy level of PT can be tuned simply by applying a bias to it in an electrolytic solution, we also investigated the effect of the energy level on the devices' performances. The power conversion efficiency of a solar cell containing a PT buffer layer reached 4.18% under AM 1.5 G irradiation (100 mW/cm(2)).
Wei
Hung-Yu
HY
Huang
Jen-Hsien
JH
Ho
Kuo-Chuan
KC
Chu
Chih-Wei
CW
D011211:Electric Power Supplies; D004566:Electrodes; D004867:Equipment Design; D019544:Equipment Failure Analysis; D008422:Materials Testing; D011108:Polymers / Q000737:chemistry* / Q000528:radiation effects*; D012993:Solar Energy; D013876:Thiophenes / Q000737:chemistry* / Q000528:radiation effects*; D014466:Ultraviolet Rays
D011108:Polymers; D013876:Thiophenes; C066730:polythiophene