We explore theoretically the effect of incorporating a thin tunnel barrier between the electron and hole transport layers of organic heterojunction photovoltaic devices. Macroscopic device characteristics (such as short-circuit current, open-circuit voltage, and power efficiency) are related to microscopic processes (such as exciton diffusion, dissociation, and recombination). We show that a tunnel barrier that alters the rates of different transfer processes at the interface between the electron and hole transport layers can significantly affect the efficiency of organic photovoltaic devices.
Bibliographical noteFunding Information:
This work was supported in part by the Los Alamos National Laboratory LDRD program XW11 and the National Science Foundation (NSF) MRSEC Program under Award No. DMR-0819885. Access to the facilities of the Minnesota Supercomputing Institute is gratefully acknowledged.