Superlattice deformation in quantum dot films on flexible substrates via uniaxial strain. Issue 3 (31st January 2023)

• Record Type: Journal Article
• Authors: Heger, Julian E.; Chen, Wei; Zhong, Huaying; Xiao, Tianxiao; Harder, Constantin; Apfelbeck, Fabian A. C.; Weinzierl, Alexander F.; Boldt, Regine; Schraa, Lucas; Euchler, Eric; Sambale, Anna K.; Schneider, Konrad; Schwartzkopf, Matthias; Roth, Stephan V.; Müller-Buschbaum, P.
• Is Part Of: Nanoscale horizons. Volume 8:Issue 3(2023)
• Page Start: 383
• Page End: 395
• Publication Date: 2023-01-31
• Subjects: Nanoscience -- Periodicals; Nanotechnology -- Periodicals; 620.505
• DOI: 10.1039/d2nh00548d
• Languages: English
• ISSNs: 2055-6756

Abstract

Abstract : Superlattice deformation in PbS quantum dot thin films introduced by uniaxial strain: In situ GISAXS study on the correlation of morphology and photoluminescence. Abstract : The superlattice in a quantum dot (QD) film on a flexible substrate deformed by uniaxial strain shows a phase transition in unit cell symmetry. With increasing uniaxial strain, the QD superlattice unit cell changes from tetragonal to cubic to tetragonal phase as measured with in situ grazing-incidence small-angle X-ray scattering (GISAXS). The respective changes in the optoelectronic coupling are probed with photoluminescence (PL) measurements. The PL emission intensity follows the phase transition due to the resulting changing inter-dot distances. The changes in PL intensity accompany a redshift in the emission spectrum, which agrees with the Förster resonance energy transfer (FRET) theory. The results are essential for a fundamental understanding of the impact of strain on the performance of flexible devices based on QD films, such as wearable electronics and next-generation solar cells on flexible substrates.