Over 15% Efficiency in Ternary Organic Solar Cells by Enhanced Charge Transport and Reduced Energy Loss

Hongtao Wang; Zhuohan Zhang; Jiangsheng Yu; Po-Chen Lin; Chu-Chen Chueh; Xin Liu; Shun Guang; Shenya Qu; Weihua Tang

doi:10.1021/acsami.0c03484

Over 15% Efficiency in Ternary Organic Solar Cells by Enhanced Charge Transport and Reduced Energy Loss

ACS Appl Mater Interfaces. 2020 May 13;12(19):21633-21640. doi: 10.1021/acsami.0c03484. Epub 2020 Apr 29.

Authors

Hongtao Wang¹, Zhuohan Zhang², Jiangsheng Yu^{1

3}, Po-Chen Lin⁴, Chu-Chen Chueh⁴, Xin Liu^{1

3}, Shun Guang¹, Shenya Qu¹, Weihua Tang²

Affiliations

¹ School of Electronic and Optical Engineering, Nanjing University of Science and Technology, Nanjing 210094, P. R. China.
² School of Chemical Engineering, Nanjing University of Science and Technology, Nanjing 210094, P. R. China.
³ MIIT Key Laboratory of Advanced Solid Laser, Nanjing University of Science and Technology, Nanjing 210094, P. R. China.
⁴ Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan.

PMID: 32314906
DOI: 10.1021/acsami.0c03484

Abstract

In this study, an efficient ternary bulk-heterojunction (BHJ) organic solar cell (OSC) is demonstrated by incorporating two acceptors, PC₆₁BM and ITC6-4F, with a polymer donor (PM6). This reveals that the addition of PC₆₁BM not only enhances the electron mobility of the derived BHJ blend but also facilitates exciton dissociation, resulting in a more balanced charge transport alongside with reduced trap-assisted charge recombination. Consequently, as compared to the pristine PM6/ITC6-4F device, the optimal ternary OSC is revealed to deliver an improved power conversion efficiency (PCE) of 15.11% with a boosted J_SC, V_OC, and fill factor (FF) simultaneously. The resultant V_OC and FF are among the highest values recorded in the literature for the ternary OSCs with a PCE exceeding 15%. This result thus suggests that besides improving the charge transport characteristics in devices, incorporating a fullerene derivative as part of the acceptor can also improve the resultant V_OC, which can reduce the energy loss to realize efficient organic photovoltaics.

Keywords: charge transport; energy transfer; fullerene derivative acceptor; open-circuit voltage; ternary organic solar cells.