Mesoscopic 3D Charge Transport in Solution-Processed Graphene-Based Thin Films: A Multiscale Analysis
Journal article, 2023
Graphene and related 2D material (GRM) thin films consist of 3D assembly of billions of 2D nanosheets randomly distributed and interacting via van der Waals forces. Their complexity and the multiscale nature yield a wide variety of electrical characteristics ranging from doped semiconductor to glassy metals depending on the crystalline quality of the nanosheets, their specific structural organization ant the operating temperature. Here, the charge transport (CT) mechanisms are studied that are occurring in GRM thin films near the metal-insulator transition (MIT) highlighting the role of defect density and local arrangement of the nanosheets. Two prototypical nanosheet types are compared, i.e., 2D reduced graphene oxide and few-layer-thick electrochemically exfoliated graphene flakes, forming thin films with comparable composition, morphology and room temperature conductivity, but different defect density and crystallinity. By investigating their structure, morphology, and the dependence of their electrical conductivity on temperature, noise and magnetic-field, a general model is developed describing the multiscale nature of CT in GRM thin films in terms of hopping among mesoscopic bricks, i.e., grains. The results suggest a general approach to describe disordered van der Waals thin films.
weak localization
graphene
phase transition
disordered systems
charge transport
Van der Waals thin films
Author
Alex Boschi
National Research Council of Italy (CNR)
Istituto Italiano di Tecnologia
Alessandro Kovtun
National Research Council of Italy (CNR)
F. Liscio
Consiglo Nazionale Delle Richerche
Zhenyuan Xia
National Research Council of Italy (CNR)
Chalmers, Industrial and Materials Science, Materials and manufacture
Kyung Ho Kim
Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics
Royal Holloway University of London
Samuel Lara Avila
Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics
Sara De Simone
Consiglo Nazionale Delle Richerche
Valentina Mussi
Consiglo Nazionale Delle Richerche
C. Barone
University of Salerno
S. Pagano
University of Salerno
Marco Gobbi
CIC nanoGUNE
Paolo Samorì
ISIS - Supramolecular Science and Engineering Institute
Marco Affronte
Dipartimento di Scienze Fisiche
Andrea Candini
National Research Council of Italy (CNR)
Vincenzo Palermo
National Research Council of Italy (CNR)
A. Liscio
Consiglo Nazionale Delle Richerche
Small
1613-6810 (ISSN) 1613-6829 (eISSN)
Vol. 19 42 2303238Graphene Core Project 3 (Graphene Flagship)
European Commission (EC) (EC/H2020/881603), 2020-04-01 -- 2023-03-31.
Areas of Advance
Nanoscience and Nanotechnology
Materials Science
Subject Categories (SSIF 2011)
Materials Chemistry
Condensed Matter Physics
DOI
10.1002/smll.202303238
PubMed
37330652