Incorporating an Electrode Modification Layer with a Vertical Phase Separated Photoactive Layer for Efficient and Stable Inverted Nonfullerene Polymer Solar Cells

Zhenzhen Shi; Hao Liu; Yaping Wang; Jinyan Li; Yiming Bai; Fuzhi Wang; Xingming Bian; Tasawar Hayat; Ahmed Alsaedi; Zhan'ao Tan

doi:10.1021/acsami.7b13494

Incorporating an Electrode Modification Layer with a Vertical Phase Separated Photoactive Layer for Efficient and Stable Inverted Nonfullerene Polymer Solar Cells

ACS Appl Mater Interfaces. 2017 Dec 20;9(50):43871-43879. doi: 10.1021/acsami.7b13494. Epub 2017 Dec 6.

Authors

Zhenzhen Shi¹, Hao Liu¹, Yaping Wang¹, Jinyan Li¹, Yiming Bai¹, Fuzhi Wang¹, Xingming Bian¹, Tasawar Hayat^{2

3}, Ahmed Alsaedi³, Zhan'ao Tan¹

Affiliations

¹ State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources, North China Electric Power University , Beijing 102206, China.
² NAAM Research Group, Faculty of Science, King Abdulaziz University , Jeddah 21589, Saudi Arabia.
³ Department of Mathematics, Quiad-I-Azam University , Islamabad 44000, Pakistan.

PMID: 29165983
DOI: 10.1021/acsami.7b13494

Abstract

For bulk heterojunction polymer solar cells (PSCs), the donors and acceptors featuring specific phase separation and concentration distribution within the electron donor/acceptor blends crucially affect the exciton dissociation and charge transportation. Herein, efficient and stable nonfullerene inverted PSCs incorporating a phase separated photoactive layer and a titanium chelate electrode modification layer are demonstrated. Water contact angle (WCA), scanning kelvin probe microscopy (SKPM), and atomic force microscopy (AFM) techniques are implemented to characterize the morphology of photoactive layers. Compared with the control conventional device, the short-circuit current density (J_sc) is enhanced from 14.74 to 17.45 mAcm^-2. The power conversion efficiency (PCE) for the inverted PSCs with a titanium (diisopropoxide)-bis-(2,4-pentanedionate) (TIPD) layer increases from 9.67% to 11.69% benefiting from the declined exciton recombination and fairly enhanced charge transportation. Furthermore, the nonencapsulated inverted device with a TIPD layer demonstrates the best long-term stability, 85% of initial PCE remaining and an almost undecayed open-circuit voltage (V_oc) after 1440 h. Our results reveal that the titanium chelate is an excellent electrode modification layer to incorporate with a vertical phase separated photoactive layer for producing high-efficiency and high-stability inverted nonfullerene PSCs.

Keywords: electrode modification layer; inverted nonfullerene polymer solar cells; long-term stability; titanium (diisopropoxide)-bis-(2,4-pentanedionate); vertical phase separation.