학술논문

Perpendicular Alignment of 2D Nanoplatelet Emitters in Electrospun Fibers: A Result of the Barus Effect?
Document Type
Article
Source
Macromolecular Materials & Engineering. Sep2023, Vol. 308 Issue 9, p1-11. 11p.
Subject
*SMALL-angle scattering
*POLARIZATION microscopy
*SOLAR concentrators
*FIBERS
*COMPOUND parabolic concentrators
*METHYL methacrylate
Language
ISSN
1438-7492
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. [ABSTRACT FROM AUTHOR]