Improved Blend Film Morphology and Free Carrier Generation Provide a High-Performance Ternary Polymer Solar Cell
Journal
ACS Applied Materials and Interfaces
Journal Volume
13
Journal Issue
1
Pages
1076-1085
Date Issued
2021
Author(s)
Abstract
Non-fullerene organic photovoltaics (OPVs) have displayed the highest power conversion efficiencies (PCEs) among OPVs. Herein, we describe a two-donor (PM6, TPD-3F)/one-acceptor (Y6) ternary blend having an optimized blend morphology that leads to improved OPV performance. Because TPD-3F has a HOMO energy level deeper than that of PM6, the value of VOC of the corresponding ternary device increased. Good miscibility between PM6 and TPD-3F, in conjunction with device optimization through the use of 1-chloronaphthalene as an additive, provided an optimized ternary blend morphology for efficient exciton dissociation and carrier transport and, therefore, larger PCE. Compared with the preoptimized PM6:Y6 binary device, the ternary device functioned with improvements in its short-circuit current density, value of VOC, and fill factor. As a result, the device PCE improved from 15.5 ± 0.19 to 16.6 ± 0.25% under AM 1.5G (100 mW cm-2) irradiation. The champion cell exhibited a PCE of 17.0% - a value that is one of the highest for a ternary OPV. Furthermore, such devices exhibited outstanding shelf lifetimes, with long-term stability in air (25 °C, 40% humidity) without encapsulation; the performance remained high (at 15.4%) after storage for 820 h. ? 2020 American Chemical Society.
Subjects
Charge carriers; Morphology; 1-chloronaphthalene; Blend morphology; Device optimization; Exciton dissociation; HOMO energy levels; Long term stability; Organic photovoltaics; Power conversion efficiencies; Polymer solar cells
SDGs
Other Subjects
Charge carriers; Morphology; 1-chloronaphthalene; Blend morphology; Device optimization; Exciton dissociation; HOMO energy levels; Long term stability; Organic photovoltaics; Power conversion efficiencies; Polymer solar cells
Type
journal article