Reliable fabrication of transparent conducting films by cascade centrifugation and Langmuir–Blodgett deposition of electrochemically exfoliated graphene

• Teodora Vićentić,
• Stevan Andrić,
• Vladimir Rajić and
• Marko Spasenović

Beilstein J. Nanotechnol. 2022, 13, 666–674, doi:10.3762/bjnano.13.58

• no exfoliation experience to make use of widely available graphene materials. Keywords: 2D materials; cascade centrifugation; graphene; Langmuir–Blodgett deposition; transparent conductors; Introduction The interest in graphene and other 2D materials keeps growing, especially since the initial

• delve into fundamental properties was augmented with an outlook towards potential applications [1]. Over the past decades, a great number of different methods for the synthesis of graphene and other 2D materials has been proposed, including micromechanical cleavage [2], chemical vapor deposition (CVD

• then break up the bulk 2D materials into mono- and few-layer nanosheets [15][16]. The choice of solvent for LPE is made based on surface energy considerations, compatible solvents include NMP, dimethylformamide (DMF), N,N-dimethylacetamide (DMA), γ-butyrolactone (GBL), 1,3-dimethyl-2-imidazolidinone

Revealing local structural properties of an atomically thin MoSe₂ surface using optical microscopy

• Lin Pan,
• Peng Miao,
• Anke Horneber,
• Alfred J. Meixner,
• Pierre-Michel Adam and
• Dai Zhang

Beilstein J. Nanotechnol. 2022, 13, 572–581, doi:10.3762/bjnano.13.49

• dichalcogenide. Keywords: copper phthalocyanine; local structure; molybdenum diselenide; optical spectroscopy; surface-enhanced Raman spectroscopy; Introduction Two-dimensional (2D) materials have garnered interest for the next generation of optoelectronic and electrochemical devices, mainly owing to their

• single-molecule detection level [18][19]. The Raman enhancement originates from an electromagnetic mechanism, provided by the excitation of surface plasmons, and a chemical mechanism which is related to the modification of Raman polarizability of molecules [20]. It has been reported that 2D materials

• orientation and molecular energy levels in the vicinity of the Fermi level of graphene, the charge-transfer effect can become more pronounced [24][25]. In summary, the structural irregularities in 2D materials and molecular probe both can impact the strength of molecule–substrate interactions and then modify

Electrostatic pull-in application in flexible devices: A review

• Teng Cai,
• Yuming Fang,
• Yingli Fang,
• Ruozhou Li,
• Ying Yu and
• Mingyang Huang

Beilstein J. Nanotechnol. 2022, 13, 390–403, doi:10.3762/bjnano.13.32

• [61]. Schematic diagram of a flexible microvalve structure. Figure 8 was redrawn from [77]. Schematic diagram of a GR pump. Figure 9 was republished from [78] (D. Davidovikj et al., “Graphene gas pumps”, 2D Materials, vol. 5, article no. 031009, published on 11 May 2018; https://doi.org/10.1088/2053

Theoretical understanding of electronic and mechanical properties of 1T′ transition metal dichalcogenide crystals

• Seyedeh Alieh Kazemi,
• Sadegh Imani Yengejeh,
• Vei Wang,
• William Wen and
• Yun Wang

Beilstein J. Nanotechnol. 2022, 13, 160–171, doi:10.3762/bjnano.13.11

• to their composition and structural polytypes. However, experimental measurements of the electronic and mechanical properties of 2D materials face the challenge of synthesizing high-quality pristine crystals. Thus, numerical simulations have become a promising alternative due to the relatively good

Progress and innovation of nanostructured sulfur cathodes and metal-free anodes for room-temperature Na–S batteries

• Marina Tabuyo-Martínez,
• Bernd Wicklein and
• Pilar Aranda

Beilstein J. Nanotechnol. 2021, 12, 995–1020, doi:10.3762/bjnano.12.75

• phosphorous/graphene anode delivered 1095 mAh·g−1 after 200 cycles at 1C [81]. It has also triggered research in a wider range of 2D materials as suitable and low-expansion anodes, starting with layered black phosphorous [73][76]. From there, exfoliated sheets of 2D allotropes came to scrutiny, such as

Molecular assemblies on surfaces: towards physical and electronic decoupling of organic molecules

• Sabine Maier and
• Meike Stöhr

Beilstein J. Nanotechnol. 2021, 12, 950–956, doi:10.3762/bjnano.12.71

• substrate and the organic building blocks. Recently, two-dimensional (2D) materials, including hexagonal boron nitride (hBN) [22][23], graphene [24][25][26][27], and MoS2 [28], have emerged as monatomically thin decoupling layers. Van der Waals 2D materials are generally well suited due to their chemical

• changing chemical environment. Next, we outline articles that use 2D materials and ultrathin dielectric layers as decoupling layers. While on the one hand, molecular functionalization is a powerful approach to tune the electronic and optical properties of 2D materials, in particular for many practical

• applications [78], 2D materials, on the other hand, offer an alternative way for decoupling molecular structures from metal substrates [24]. 2D van der Waals materials are generally inert and therefore, are potentially well suited for physical decoupling of molecular structures. However, moiré patterns present

The role of convolutional neural networks in scanning probe microscopy: a review

• Ido Azuri,
• Irit Rosenhek-Goldian,
• Neta Regev-Rudzki,
• Georg Fantner and
• Sidney R. Cohen

Beilstein J. Nanotechnol. 2021, 12, 878–901, doi:10.3762/bjnano.12.66

• crystals (van der Waals heterostructures, graphene, hBN, MoS2, and WTe2) was demonstrated. The detection algorithm enables real-time detection of the 2D materials (running for 200 ms on a 1024 × 1024 optical image) and is insensitive to variations in microscopy conditions such as illumination and color

Prediction of Co and Ru nanocluster morphology on 2D MoS₂ from interaction energies

• Cara-Lena Nies and
• Michael Nolan

Beilstein J. Nanotechnol. 2021, 12, 704–724, doi:10.3762/bjnano.12.56

• gap in understanding thin film nucleation on 2D materials. In this paper, we present a density functional theory (DFT) study of the adsorption of small Co and Ru structures, with up to four atoms, on a monolayer of MoS2. We explore how the metal–substrate and metal–metal interactions contribute to the

• . Based on this understanding, we propose Co on MoS2 as a suitable candidate for advanced interconnects, while Ru on MoS2 is more suited to catalysis applications. Keywords: cobalt (Co); 2D materials; molybdenum disulfide (MoS2); ruthenium (Ru); thin film nucleation; Introduction Layered materials that

• or doping with transition metals [4][5][18][19][20][21][22], alkali and alkali earth metals [23][24][25], and non-metals [25] on MoS2 and other 2D materials. While experimental studies can be used to probe the performance of the 2D material in a device or some of the interfacial interactions between

A review of defect engineering, ion implantation, and nanofabrication using the helium ion microscope

• Frances I. Allen

Beilstein J. Nanotechnol. 2021, 12, 633–664, doi:10.3762/bjnano.12.52

• function [30]. In several of these works, high-resolution scanning TEM (STEM) imaging has been performed to enable the analysis of the defects created on the atomic scale [26][29][30] (see, e.g., Figure 2c). Apart from 2D materials, thin-film samples have also been the subject of electronic property tuning

Properties of graphene deposited on GaN nanowires: influence of nanowire roughness, self-induced nanogating and defects

• Jakub Kierdaszuk,
• Piotr Kaźmierczak,
• Justyna Grzonka,
• Aleksandra Krajewska,
• Aleksandra Przewłoka,
• Wawrzyniec Kaszub,
• Zbigniew R. Zytkiewicz,
• Marta Sobanska,
• Maria Kamińska,
• Andrzej Wysmołek and
• Aneta Drabińska

Beilstein J. Nanotechnol. 2021, 12, 566–577, doi:10.3762/bjnano.12.47

• impacted graphene carrier concentration and strain. It is, therefore, possible to consider the use of NW substrates for defect engineering in graphene and probably in other 2D materials. SEM images of graphene on GaN NWs with different variations in height in N0 (a,d), N100 (b,e), and N500 (c,f) samples

Reconstruction of a 2D layer of KBr on Ir(111) and electromechanical alteration by graphene

• Zhao Liu,
• Antoine Hinaut,
• Stefan Peeters,
• Sebastian Scherb,
• Ernst Meyer,
• Maria Clelia Righi and
• Thilo Glatzel

Beilstein J. Nanotechnol. 2021, 12, 432–439, doi:10.3762/bjnano.12.35

• reduced by the decoupling effect of graphene, thus yielding different electrical and mechanical properties of the top KBr layer. Keywords: DFT; graphene; Ir(111); KBr; KPFM; nc-AFM; surface reconstruction; Introduction Many two-dimensional (2D) materials have excellent optical, mechanical

Exploring the fabrication and transfer mechanism of metallic nanostructures on carbon nanomembranes via focused electron beam induced processing

• Christian Preischl,
• Linh Hoang Le,
• Elif Bilgilisoy,
• Armin Gölzhäuser and
• Hubertus Marbach

Beilstein J. Nanotechnol. 2021, 12, 319–329, doi:10.3762/bjnano.12.26

• reduction of the iron structures. These results demonstrate that the fabrication of hybrids of metallic nanostructures onto organic 2D materials is an intrinsically complex procedure. The interactions among the metallic deposits, the substrate for the growth of the SAM, and the associated etching/dissolving

• agent need to be considered and further studied. Keywords: 2D materials; carbon nanomembranes (CNMs); focused electron beam-induced processing; metallic nanostructures; self-assembled monolayers; Introduction Focused electron beam-induced processing (FEBIP) is a powerful maskless “direct-write

• effects caused by secondary or backscattered electrons have minor influence on size and shape of the deposit. Recently, it could be demonstrated that FEBIP can be used to fabricate functional hybrid structures consisting of metallic nanostructures on top of organic 2D materials. The prototype of organic

The patterning toolbox FIB-o-mat: Exploiting the full potential of focused helium ions for nanofabrication

• Victor Deinhart,
• Lisa-Marie Kern,
• Jan N. Kirchhof,
• Sabrina Juergensen,
• Joris Sturm,
• Enno Krauss,
• Thorsten Feichtner,
• Sviatoslav Kovalchuk,
• Michael Schneider,
• Dieter Engel,
• Bastian Pfau,
• Bert Hecht,
• Kirill I. Bolotin,
• Stephanie Reich and
• Katja Höflich

Beilstein J. Nanotechnol. 2021, 12, 304–318, doi:10.3762/bjnano.12.25

• devices by design, that is, to tailor both material properties and device geometries according to a sophisticated blueprint. Thin layers and two-dimensional (2D) materials are especially interesting candidates for designer materials [1] as they are compatible with planar device geometries and may be

• , other challenges such as small sputter rates and large interaction volumes persist. Therefore, 2D materials are an ideal platform for ion beam machining with light ions. The lack (or non-relevance) of the interaction volume allows for a high spatial resolution, enabling the fabrication of structural

• features in the single-digit nanometer range where small sputter rates play a minor role. This holds true not only for monolayer 2D materials, such as graphene, but also for thin films forming quasi 2D geometries. The versatility of the corresponding materials opens a wide field of exciting applications

ZnO and MXenes as electrode materials for supercapacitor devices

• Ameen Uddin Ammar,
• Ipek Deniz Yildirim,
• Feray Bakan and
• Emre Erdem

Beilstein J. Nanotechnol. 2021, 12, 49–57, doi:10.3762/bjnano.12.4

• supercapacitor device are important factors in this scenario. Nowadays, ZnO as metal oxide and MXene as 2D materials are the rising stars of electrode materials in supercapacitors due to their highly controllable properties. Therefore, we review the findings about ZnO and MXene in terms of defect structures and

• because of its unique properties, such as ultrathin structure and heterojunction behavior [15]. In the search of other 2D materials, MXenes, which are a novel class of 2D metal carbides, were discovered at Drexel University in 2011 during research in which MAX phases were used as electrode materials in

• potential to be used as an electrode material in supercapacitors. The techniques of structural defect characterization in metal oxides can be applied to 2D materials such as MXenes. We are indeed aiming to transfer the knowledge about semiconductors to 2D materials using the two prototype materials ZnO and

Nanomechanics of few-layer materials: do individual layers slide upon folding?

• Ronaldo J. C. Batista,
• Rafael F. Dias,
• Ana P. M. Barboza,
• Alan B. de Oliveira,
• Taise M. Manhabosco,
• Thiago R. Gomes-Silva,
• Matheus J. S. Matos,
• Andreij C. Gadelha,
• Cassiano Rabelo,
• Luiz G. L. Cançado,
• Ado Jorio,
• Hélio Chacham and
• Bernardo R. A. Neves

Beilstein J. Nanotechnol. 2020, 11, 1801–1808, doi:10.3762/bjnano.11.162

• materials, also called “2D materials”, after exfoliation, eventually creating folded edges across the resulting flakes. We investigate the adhesion and flexural properties of single-layered and multilayered 2D materials upon folding in the present work. This is accomplished by measuring and modeling

• mechanical properties of folded edges, which allows for the experimental determination of the bending stiffness (κ) of multilayered 2D materials as a function of the number of layers (n). In the case of talc, we obtain κ ∝ n3 for n ≥ 5, indicating no interlayer sliding upon folding, at least in this

• interlayer interactions, have been the primary source of 2D materials [1]. These 2D materials exhibit unusual behavior associated regarding their flexural and adhesive properties [2][3][4][5][6][7][8]. For instance, self-assembled folded flaps and nanoribbons of graphene form by spontaneous folding, sliding

Mapping of integrated PIN diodes with a 3D architecture by scanning microwave impedance microscopy and dynamic spectroscopy

• Rosine Coq Germanicus,
• Peter De Wolf,
• Florent Lallemand,
• Catherine Bunel,
• Serge Bardy,
• Hugues Murray and
• Ulrike Lüders

Beilstein J. Nanotechnol. 2020, 11, 1764–1775, doi:10.3762/bjnano.11.159

• local electrical properties of the scanned material are determined without the need of an applied voltage. Some studies reported sMIM measurements performed in doped semiconductors [22] deposited onto FEOL layers, ferroelectrics [23], or 2D materials [22][24]. Here, sMIM was employed to analyse a

Imaging and milling resolution of light ion beams from helium ion microscopy and FIBs driven by liquid metal alloy ion sources

• Nico Klingner,
• Gregor Hlawacek,
• Paul Mazarov,
• Wolfgang Pilz,
• Fabian Meyer and
• Lothar Bischoff

Beilstein J. Nanotechnol. 2020, 11, 1742–1749, doi:10.3762/bjnano.11.156

• formation of helium bubbles in the substrate when using high fluences [5]. In addition to many imaging applications, HIM has been used to create and study new device concepts, including the fabrication of nanometer-sized ferromagnets [6], the controlled tuning of memristive properties of 2D materials [7

Effect of localized helium ion irradiation on the performance of synthetic monolayer MoS₂ field-effect transistors

• Jakub Jadwiszczak,
• Pierce Maguire,
• Conor P. Cullen,
• Georg S. Duesberg and
• Hongzhou Zhang

Beilstein J. Nanotechnol. 2020, 11, 1329–1335, doi:10.3762/bjnano.11.117

• , we find that irradiating the electrode–channel interface has a deleterious impact on charge transport when contrasted with irradiations confined only to the transistor channel. Keywords: 2D materials; contacts; defect engineering; helium ion microscope; ion beam doping; vacancies; two-dimensional

Hybridization vs decoupling: influence of an h-BN interlayer on the physical properties of a lander-type molecule on Ni(111)

• Maximilian Schaal,
• Takumi Aihara,
• Marco Gruenewald,
• Felix Otto,
• Jari Domke,
• Roman Forker,
• Hiroyuki Yoshida and
• Torsten Fritz

Beilstein J. Nanotechnol. 2020, 11, 1168–1177, doi:10.3762/bjnano.11.101

• , Chiba 263-8522, Japan Molecular Chirality Research Center, Chiba University, 1-33, Yayoi-cho, Inage-ku, Chiba 263-8522, Japan 10.3762/bjnano.11.101 Abstract 2D materials such as hexagonal boron nitride (h-BN) are widely used to decouple organic molecules from metal substrates. Nevertheless, there are

Monolayers of MoS₂ on Ag(111) as decoupling layers for organic molecules: resolution of electronic and vibronic states of TCNQ

• Asieh Yousofnejad,
• Gaël Reecht,
• Nils Krane,
• Christian Lotze and
• Katharina J. Franke

Beilstein J. Nanotechnol. 2020, 11, 1062–1071, doi:10.3762/bjnano.11.91

• decouple such flat-lying molecules from a metal, thin insulating layers have been engineered, ranging from ionic salts [15][16], over oxides [17][18][19], nitrides [20], and molecular layers [21][22] to 2D materials, such as graphene [23][24], and hexagonal boron nitride [25]. The most recent development

Simulations of the 2D self-assembly of tripod-shaped building blocks

• Łukasz Baran,
• Wojciech Rżysko and
• Edyta Słyk

Beilstein J. Nanotechnol. 2020, 11, 884–890, doi:10.3762/bjnano.11.73

• diffraction pattern and average association number. Keywords: 2D materials; coarse-grained model; molecular simulations; self-assembly; structural characterization; tripod building blocks; Introduction On-surface synthesis is a newly developing field in chemistry that aims at making use of solid surfaces as

Templating effect of single-layer graphene supported by an insulating substrate on the molecular orientation of lead phthalocyanine

• K. Priya Madhuri,
• Abhay A. Sagade,
• Pralay K. Santra and
• Neena S. John

Beilstein J. Nanotechnol. 2020, 11, 814–820, doi:10.3762/bjnano.11.66

• molecules are influenced by the nature of the substrate, which has been attributed to different substrate–molecule interactions [9]. With the application of 2D materials, such as graphene in device configurations, it is important to understand the orientation of MPc molecules on these atomically thin

Hexagonal boron nitride: a review of the emerging material platform for single-photon sources and the spin–photon interface

• Stefania Castelletto,
• Faraz A. Inam,
• Shin-ichiro Sato and
• Alberto Boretti

Beilstein J. Nanotechnol. 2020, 11, 740–769, doi:10.3762/bjnano.11.61

• methods also have limitations such as sample damaging or even destruction. Further 2D materials are more likely to be manufactured within existing devices as such following a hybrid approach. Hybrid approaches are the ones mostly pursued; however, they suffer from poor performance due to mismatch

• centers is positively correlated with neutron fluence. This approach suggests that the atomic origin of the color centers emitting at 580 nm is the VB3N1 and it is a viable method to achieve an ensemble of SPEs. SPEs in 2D materials have proved to be resistant to gamma-ray irradiation [128]. We can

Effect of substitutional defects on resonant tunneling diodes based on armchair graphene and boron nitride nanoribbons lateral heterojunctions

• Majid Sanaeepur

Beilstein J. Nanotechnol. 2020, 11, 688–694, doi:10.3762/bjnano.11.56

• heterojunction; armchair boron nitride nanoribbon (ABNNR); armchair graphene nanoribbon (AGNR); negative differential resistance (NDR); nonequilibrium Green’s function (NEGF); resonant tunneling diode (RTD); substitutional defects; Introduction 2D materials have gained tremendous research interest due to the

• electronic devices have been realized by heterostructures based on vertical stacking or lateral stitching of 2D materials with different electronic properties [6]. Lateral graphene/hexagonal boron nitride (Gr/hBN) heterostructures, due to very low lattice mismatch between graphene and hBN, are most suitable

• energies to form a planar 3D structure in which the direction of carrier transport is perpendicular to the interface of stacked materials [21][22][23]. In recent years, a few RTD structures based on 2D materials have been proposed [24][25][26]. In such RTDs the bandgap difference needed for normal

Interfacial charge transfer processes in 2D and 3D semiconducting hybrid perovskites: azobenzene as photoswitchable ligand

• Nicole Fillafer,
• Tobias Seewald,
• Lukas Schmidt-Mende and
• Sebastian Polarz

Beilstein J. Nanotechnol. 2020, 11, 466–479, doi:10.3762/bjnano.11.38

• , for the particles after irradiation. Compared to the d(001) values of the initial 2D materials, we could not observe any change. Considering the results of 1H NMR in combination with PXRD no significant photoswitching of the azobenzene molecules is detected. Recently published calculations showed that