Ultrafast Charge and Exciton Diffusion in Monolayer Films of 9-Armchair Graphene Nanoribbons
Varghese, Sebin (Institut Català de Nanociència i Nanotecnologia)
Wang, Hai I. (Utrecht University. Debye Institute for Nanomaterials Science)
Wuttke, Michael (Max Planck Institute for Polymer Research)
Zhou, Yazhou (Max Planck Institute for Polymer Research)
Müllen, Klaus (Max Planck Institute for Polymer Research)
Narita, Akimitsu (Okinawa Institute of Science and Technology Graduate University)
Cummings, Aron (Institut Català de Nanociència i Nanotecnologia)
Tielrooij, Klaas-Jan (Institut Català de Nanociència i Nanotecnologia)
Mehew, Jake Dudley (Institut Català de Nanociència i Nanotecnologia)

Date:	2024
Abstract:	Determining the electronic transport properties of graphene nanoribbons is crucial for assessing their suitability for applications. So far, this has been highly challenging both through experimental and theoretical approaches. This is particularly the case for graphene nanoribbons that are prepared by chemical vapor deposition, which is a scalable and industry-compatible bottom-up growth method that results in closely packed arrays of ribbons with relatively short lengths of a few tens of nanometers. In this study, the experimental technique of spatiotemporal microscopy is applied to study monolayer films of 9-armchair graphene nanoribbons prepared using this growth method, and combined with linear-scaling quantum transport calculations of arrays of thousands of nanoribbons. Both approaches directly resolve electronic spreading in space and time through diffusion and give an initial diffusivity approaching 200 cm2 s-1 during the first picosecond after photoexcitation. This corresponds to a mobility up to 550 cm2 V-1 s-1. The quasi-free carriers then form excitons, which spread with a diffusivity of tens of cm2 s-1. The results indicate that this relatively large charge carrier mobility is the result of electronic transport not being hindered by defects nor inter-ribbon hopping. This confirms their suitability for applications that require efficient electronic transport.
Grants:	Ministerio de Economía y Competitividad FPI-SO2018 European Commission 804349 Agencia Estatal de Investigación PID2022-142730NB-I00 Agencia Estatal de Investigación CEX2021-001214-S
Note:	Altres ajuts: CERCA Programme/Generalitat de Catalunya
Rights:	Aquest document està subjecte a una llicència d'ús Creative Commons. Es permet la reproducció total o parcial, la distribució, la comunicació pública de l'obra i la creació d'obres derivades, fins i tot amb finalitats comercials, sempre i quan es reconegui l'autoria de l'obra original.
Language:	Anglès
Document:	Article ; recerca ; Versió publicada
Subject:	Charge mobility ; Excitons ; Graphene nanoribbons ; Spatiotemporal microscopy
Published in:	Advanced materials, Vol. 36, Issue 50 (December 2024) , art. 2407796, ISSN 1521-4095

DOI: 10.1002/adma.202407796
PMID: 39466850

8 p, 1.9 MB

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Research literature > UAB research groups literature > Research Centres and Groups (research output) > Experimental sciences > Catalan Institute of Nanoscience and Nanotechnology (ICN2)
Articles > Research articles
Articles > Published articles