Local structure of semicrystalline P3HT films probed by nanofocused coherent x-rays

TL;DR

This study uses nanofocused coherent x-ray analysis to investigate the local crystalline structure of semicrystalline P3HT films, revealing how gold nanoparticles influence domain orientation and size at the nanoscale.

Contribution

It introduces the application of x-ray cross-correlation analysis to spatially map crystalline domain orientation and size in P3HT films with embedded gold nanoparticles.

Findings

Gold nanoparticles induce increased ordering of crystalline domains.

Crystalline domain size is approximately 10 nm.

Spatial maps show transition from face-on to edge-on morphology.

Abstract

We present results of an x-ray study of structural properties of semicrystalline polymer films using nanofocused x-ray beam. We applied the x-ray cross-correlation analysis (XCCA) to scattering data from blends of poly(3-hexylthiophene) (P3HT) embedded with gold nanoparticles (AuNPs). Spatially resolved maps of orientational distribution of crystalline domains allow us to distinguish sample regions of predominant face-on morphology,with a continuous transition to edge-on morphology. The average size of crystalline domains was determined to be of the order of 10 nm. As compared to pristine P3HT film, the P3HT/AuNPs blend is characterized by substantial ordering of crystalline domains, which can be induced by Au nanoparticles. The inhomogeneous structure of the polymer film is clearly visualized on the spatially resolved nanoscale 2D maps obtained using XCCA. Our results suggest that the observed changes of the polymer matrix within crystalline regions can be attributed to nanoconfinement in the presence of gold nanoparticles.