Efficient zinc phthalocyanine/C60 heterojunction photovoltaic devices employing tetracene anode interfacial layers.
We report the development of efficient small molecular organic photovoltaic devices incorporating tetracene anode interfacial layers. Planar heterojunction devices employing the tetracene anode interfacial layer achieved an EQE enhancement of 150% in the spectral region corresponding to ZnPc absorption. We demonstrate that this enhancement is due to the combined effect of the tetracene layer providing exciton-blocking at the anode/donor interface and potentially an increase in the exciton diffusion length in the ZnPc layer due to increased crystallinity and more preferred molecular stacking orientation. A power conversion efficiency of 4.7% was achieved for a planar heterojunction of a modified zinc phthalocyanine based material and C60 when employing the tetracene anode interfacial layer. By utilizing a planar-mixed heterojunction structure a peak EQE of nearly 70% and a power conversion efficiency of 5.8% was achieved.
Department of Material Science and Engineering, Arizona State University , Tempe, Arizona 85284, United States.
Tyler B
TB
Fleetham
John P
JP
Mudrick
Weiran
W
Cao
Kody
K
Klimes
Jiangeng
J
Xue
Jian
J
Li