As a benchmark semiconducting polymer, poly(3-hexyl-thiophene) (P3HT) has been broadly used to construct a wide range of organic electronic devices such as photovoltaic cells, photodetectors, thermoelectrics, and transistors. However, in comparison with P3HT:fullerene systems, the blends of P3HT with emerging nonfullerene acceptors remain significantly less explored and the structure-performance relationships are not well established. In this work, time-dependent grazing incidence X-ray scattering and real-space microscopy experiments were carried out to monitor the microstructure change of the high-efficiency blend of P3HT and a Y6-type nonfullerene acceptor (i.e., ZY-4Cl) over the duration of thermal annealing. Attractively, we observed profound changes in all the photovoltaic parameters (open-circuit voltage, current density, fill factor, and power conversion efficiency) within the first 1 minute, while a slight variation emerged in the later stage. By precisely manipulating the crystalline order of both the donor and acceptor, the P3HT:ZY-4Cl blend film subject to thermal annealing for merely 30 seconds gave rise to a remarkable power conversion efficiency of 10.7%, which is the best efficiency of P3HTbased organic photovoltaic cells at present. This is significantly higher than the efficiency of conventional annealing for 10 min (9.3%) and approximately 20 times that of as cast devices (0.5%). The research shed light on the morphological optimization and cost-effective processing of polythiophene:nonfullerene blends for optoelectronic applications.

Time-dependent morphology enables delicate crystallinity control of an efficient P3HT: Nonfullerene blend

Fall 2022 abstracts, posters, and presentations will launch in mid-September.

ACS Fall 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.