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The essence and efficiency limits of bulk-heterostructure organic solar cells: A polymer-to-panel perspective

Published online by Cambridge University Press:  07 February 2013

Muhammad A. Alam ,
Biwajit Ray ,
Mohammad Ryyan Khan  and
Sourabh Dongaonkar
Muhammad A. Alam*
Affiliation:
School of Electrical and Computer Engineering, Purdue University, West Lafayette, Indiana 47906
Biwajit Ray
Affiliation:
School of Electrical and Computer Engineering, Purdue University, West Lafayette, Indiana 47906
Mohammad Ryyan Khan
Affiliation:
School of Electrical and Computer Engineering, Purdue University, West Lafayette, Indiana 47906
Sourabh Dongaonkar
Affiliation:
School of Electrical and Computer Engineering, Purdue University, West Lafayette, Indiana 47906
*
a)Address all correspondence to this author. e-mail: [email protected]
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Abstract

Bulk-heterojunction organic photovoltaic (BHJ-OPV) technology promises high efficiency at ultralow cost and weight, with potential for nontraditional applications such as building-integrated photovoltaic (PV). There is a widespread presumption that the complexity of morphology makes carrier transport in OPV irreducibly complicated and, possibly, beyond predictive modeling. However, understanding the complex morphology is important because it not only dictates cell efficiency but also the panel performance and the operating lifetime. In this paper, we derive the fundamental thermodynamic as well as morphology-specific practical limits of BHJ-OPV efficiency and lifetime. We find that performance improvement relies not only on morphology engineering but also on increasing the effective mobility–lifetime (μτ) product, the cross-gap between donor/acceptors, and reducing the series resistance. Even if the OPV fails to achieve the highest efficiency anticipated by the thermodynamic limit, its novel form factor, lightweight, and transparency can make it a commercially viable option for many applications.

Type
Invited Feature Paper
Information
Journal of Materials Research , Volume 28 , Issue 4 , 28 February 2013 , pp. 541 - 557
Copyright
Copyright © Materials Research Society 2012

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