Perpendicular Alignment of 2D Nanoplatelet Emitters in Electrospun Fibers

A Result of the Barus Effect?

authored by

Xu Liu, Fuzhao Li, Manuel Hohgardt, Lars Frederik Klepzig, Marcel Maximilian Willich, Henrik Alexander Christ, Andreas Schaate, Peter Behrens, Jannika Lauth, Henning Menzel, Peter Jomo Walla

Abstract

Stable jet electrospinning (SJES) is a special form of optical fiber generation that prevents chaotic fiber whipping typical for conventional electrospinning procedures. Incorporation of highly emissive semiconductor nanoplatelets (NPLs) in such fibers has very high potential in optical data transmission, optological circuits, fiber lasers, solar light concentrators and many other fields because NPLs exhibit strongly directed emission from their surface plane due to various in-plane transition dipole moments. However, potential orientation control of 2D-NPLs in SJES is entirely unknown as electric fields and various mechanical forces contribute in a complex manner simultaneously. Here, the observation of counter-intuitive yet very beneficial orientation of rectangular CdSe/CdS 2D-NLP in SJES perpendicular to the fiber drawing axis is reported. Scanning electron microscopy, 3D-single particle excitation polarization microscopy, 3D-photogoniometry, polarized emission spectroscopy and small angle X-ray scattering (SAXS) demonstrate aggregation free perpendicular alignment of the NPLs in poly(methyl methacrylate) (PMMA) fibers, resulting in dominant emission in directions parallel to the fiber. It is suggested that the observed vertical alignment is due to normal forces resulting from viscoelastic expansion when the polymer solution leaves the cannula (Barus effect) and that using such perpendicular nano-emitter alignment forces allows for the generation of novel materials also beyond fibers.

Organisation(s)

Institute of Physical Chemistry and Electrochemistry
PhoenixD: Photonics, Optics, and Engineering - Innovation Across Disciplines
Inorganic Solid State and Materials Chemistry group

External Organisation(s)

Technische Universität Braunschweig
Max-Planck Institute for Multidisciplinary Sciences
University of Tübingen

Type

Article

Journal

Macromolecular Materials and Engineering

Volume

308

ISSN

1438-7492

Publication date

15.09.2023

Publication status

Published

Peer reviewed

Yes

ASJC Scopus subject areas

Chemical Engineering(all), Polymers and Plastics, Organic Chemistry, Materials Chemistry

Electronic version(s)

https://doi.org/10.1002/mame.202300027 (Access: Open)