Third Crystalline Form of P(NDI2OD-T2) with Pronounced End-on Texture

Doan Vu; Wen Liang Tan; Lu He; Alexander Ehm; Dietrich R T Zahn; Christopher R McNeill

doi:10.1021/acsmacrolett.2c00402

Third Crystalline Form of P(NDI2OD-T2) with Pronounced End-on Texture

ACS Macro Lett. 2023 Feb 21;12(2):140-146. doi: 10.1021/acsmacrolett.2c00402. Epub 2023 Jan 13.

Authors

Doan Vu¹, Wen Liang Tan¹, Lu He^{2

3}, Alexander Ehm^{2

3}, Dietrich R T Zahn^{2

3}, Christopher R McNeill¹

Affiliations

¹ Department of Materials Science and Engineering, Monash University, Clayton, Victoria 3800, Australia.
² Semiconductor Physics, Chemnitz University of Technology, D-09107 Chemnitz, Germany.
³ Center for Materials, Architectures, and Integration of Nanomembranes (MAIN), Chemnitz University of Technology, 09107 Chemnitz, Germany.

PMID: 36638049
DOI: 10.1021/acsmacrolett.2c00402

Abstract

We report the observation of a third crystalline polymorph, "form III", of the well-studied electron-transporting conjugated polymer P(NDI2OD-T2) that exhibits end-on texture. This third polymorph of P(NDI2OD-T2) is distinguished from other polymorphs by having two monomer units incorporated along the backbone-stacking direction, resulting in a doubling of the c axis of the unit cell. Form III crystallites are realized by melt-annealing a thin film followed by slow cooling. The distinct packing of this third polymorph is established through the application of grazing-incidence wide-angle X-ray scattering (GIWAXS) measurements combined with peak simulation of candidate unit cells. The discovery of a third polymorph of P(NDI2OD-T2) provides a fresh opportunity for studying structure/function relationships of this important semiconducting polymer.