Solar Energy Materials and Solar Cells, Vol.112, 73-77, 2013
The effect of built-in field on the interface exciton recombination and dissociation in N-N type organic solar cells
The free carrier generation processes at the interface formed by fullerene (C-60) and perfluorinated hexadecafluorophthalo-cyaninatozinc (F16ZnPc) are investigated in detail. It is found that the exciton dissociation and recombination across the interface can happen at the same C-60/F16ZnPc interface. And it is demonstrated in this study that both processes can be the dominant process for photocurrent generation by simply changing the direction of the built-in electric field. The observed superlinear dependence between photocurrent and light intensity confirms that the photocurrent indeed is the second order to the incident light intensity. Thus the photocurrent can be generated from the exciton recombination across the C-60/F16ZnPc interface. (C) 2013 Elsevier B.V. All rights reserved.