materials-logo

Journal Browser

Journal Browser

Carbon-Based Materials

A special issue of Materials (ISSN 1996-1944). This special issue belongs to the section "Carbon Materials".

Deadline for manuscript submissions: closed (31 May 2021) | Viewed by 41196

Printed Edition Available!
A printed edition of this Special Issue is available here.

Special Issue Editor


E-Mail Website
Guest Editor
Institute for Metals Superplasticity Problems of RAS, Ufa, Russia
Interests: graphene; mechanical properties; molecular dynamics; carbon nanostructures; plastic deformation; diamond
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

The aim of this Special Issue is to present the state-of-the-art research progress in the field of carbon-based nanomaterials. Since the experimental discovery of graphene in 2004, the field of carbon nanostructures has become one of the fast developed fields of science. In addition to studying the basic polymorphs of carbon (nanotubes, fullerenes, and graphene), carbon nanostructures of various morphology have been extensively studied. Moreover, new carbon materials with improved mechanical, electrical, chemical, and optical properties are predicted and considered to be very promising for practical application. The properties of such nanomaterials are commonly determined by their structural features.

The transition from carbon polymorphs to three-dimensional nanomaterials of complex architecture is currently an important task of material science. It is necessary to determine the possibilities of the existence of such structures at macroscopic and microscopic levels and examine in detail their properties to create a new generation of functional materials. Carbon-based materials in the form of films, fabrics, aerogels or microstructural materials are known by their large surface areas and pore volumes, light weight, a great variety of structural morphology, and how promising they are for nanoelectronics, energy storage, gas sensing, to name a few.

It is my pleasure to invite you to submit a manuscript for this Special Issue. Full papers, communications, and reviews are all welcome.

Prof. Dr. Julia A. Baimova
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Materials is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • graphene
  • carbon nanotubes
  • fullerenes
  • carbon nanostructures

Published Papers (14 papers)

Order results
Result details
Select all
Export citation of selected articles as:

Research

Jump to: Review

15 pages, 174805 KiB  
Article
Effect of Nanoparticle Size on the Mechanical Strength of Ni–Graphene Composites
by Karina A. Krylova, Liliya R. Safina, Ramil T. Murzaev, Julia A. Baimova and Radik R. Mulyukov
Materials 2021, 14(11), 3087; https://doi.org/10.3390/ma14113087 - 04 Jun 2021
Cited by 10 | Viewed by 2334
Abstract
The effect of the size of nickel nanoparticles on the fabrication of a Ni–graphene composite by hydrostatic pressure at 0 K followed by annealing at 1000 and 2000 K is studied by molecular dynamics simulation. Crumpled graphene, consisting of crumpled graphene flakes interconnected [...] Read more.
The effect of the size of nickel nanoparticles on the fabrication of a Ni–graphene composite by hydrostatic pressure at 0 K followed by annealing at 1000 and 2000 K is studied by molecular dynamics simulation. Crumpled graphene, consisting of crumpled graphene flakes interconnected by van der Waals forces is chosen as the matrix for the composite and filled with nickel nanoparticles composed of 21 and 47 atoms. It is found that the main factors that affect composite fabrication are nanoparticle size, the orientation of the structural units, and temperature of the fabrication process. The best stress–strain behavior is achieved for the Ni/graphene composite with Ni47 nanoparticle after annealing at 2000 K. However, all of the composites obtained had strength property anisotropy due to the inhomogeneous distribution of pores in the material volume. Full article
(This article belongs to the Special Issue Carbon-Based Materials)
Show Figures

Figure 1

10 pages, 2885 KiB  
Article
DABCO Derived Nitrogen-Doped Carbon Nanotubes for Oxygen Reduction Reaction (ORR) and Removal of Hexavalent Chromium from Contaminated Water
by Vadahanambi Sridhar and Hyun Park
Materials 2021, 14(11), 2871; https://doi.org/10.3390/ma14112871 - 27 May 2021
Cited by 2 | Viewed by 1903
Abstract
Though chemically-derived reduced graphene oxide (CDG) from graphite oxide (GO) precursors is a widely practiced procedure for the large-scale production of graphene, the quality and quantity of thus obtained CDG is dependent on the reduction strategy used. In this work, we report an [...] Read more.
Though chemically-derived reduced graphene oxide (CDG) from graphite oxide (GO) precursors is a widely practiced procedure for the large-scale production of graphene, the quality and quantity of thus obtained CDG is dependent on the reduction strategy used. In this work, we report an all-solid-state, residue-free, microwave process for the reduction of graphene oxide and subsequent growth of carbon nanotube ‘separators’ from a single precursor, namely DABCO (1,4-diazabicyclo[2.2.2]octane). The utility of our newly developed technique in efficiently and effectively reducing graphene oxide and in growing nitrogen-doped carbon nanotubes via catalysts like palladium and iron into unique mesoporous, 3-D hierarchical carbon nanostructures is demonstrated. The applicability of the thus obtained palladium embedded in Pd@NCNT-rGO nanoarchitectures for the oxygen reduction reaction (ORR) is investigated. When carbon fiber (CF) was used as the substrate, three-dimensional Fe@NCNT-CF were obtained, whose capability as versatile adsorbents for hexavalent chromium ion removal from contaminated waters was also demonstrated. Full article
(This article belongs to the Special Issue Carbon-Based Materials)
Show Figures

Figure 1

13 pages, 69258 KiB  
Article
Crumpled Graphene-Storage Media for Hydrogen and Metal Nanoclusters
by Liliya R. Safina, Karina A. Krylova, Ramil T. Murzaev, Julia A. Baimova and Radik R. Mulyukov
Materials 2021, 14(9), 2098; https://doi.org/10.3390/ma14092098 - 21 Apr 2021
Cited by 9 | Viewed by 1905
Abstract
Understanding the structural behavior of graphene flake, which is the structural unit of bulk crumpled graphene, is of high importance, especially when it is in contact with the other types of atoms. In the present work, crumpled graphene is considered as storage media [...] Read more.
Understanding the structural behavior of graphene flake, which is the structural unit of bulk crumpled graphene, is of high importance, especially when it is in contact with the other types of atoms. In the present work, crumpled graphene is considered as storage media for two types of nanoclusters—nickel and hydrogen. Crumpled graphene consists of crumpled graphene flakes bonded by weak van der Waals forces and can be considered an excellent container for different atoms. Molecular dynamics simulation is used to study the behavior of the graphene flake filled with the nickel nanocluster or hydrogen molecules. The simulation results reveal that graphene flake can be considered a perfect container for metal nanocluster since graphene can easily cover it. Hydrogen molecules can be stored on graphene flake at 77 K, however, the amount of hydrogen is low. Thus, additional treatment is required to increase the amount of stored hydrogen. Remarkably, the size dependence of the structural behavior of the graphene flake filled with both nickel and hydrogen atoms is found. The size of the filling cluster should be chosen in comparison with the specific surface area of graphene flake. Full article
(This article belongs to the Special Issue Carbon-Based Materials)
Show Figures

Figure 1

12 pages, 2738 KiB  
Article
Effects of Boron Carbide on Coking Behavior and Chemical Structure of High Volatile Coking Coal during Carbonization
by Qiang Wu, Can Sun, Zi-Zong Zhu, Ying-Dong Wang and Chong-Yuan Zhang
Materials 2021, 14(2), 302; https://doi.org/10.3390/ma14020302 - 08 Jan 2021
Cited by 6 | Viewed by 1590
Abstract
Modified cokes with improved resistance to CO2 reaction were produced from a high volatile coking coal (HVC) and different concentrations of boron carbide (B4C) in a laboratory scale coking furnace. This paper focuses on modification mechanism about the influence of [...] Read more.
Modified cokes with improved resistance to CO2 reaction were produced from a high volatile coking coal (HVC) and different concentrations of boron carbide (B4C) in a laboratory scale coking furnace. This paper focuses on modification mechanism about the influence of B4C on coking behavior and chemical structure during HVC carbonization. The former was studied by using a thermo-gravimetric analyzer. For the latter, four semi-cokes prepared from carbonization tests for HVC with or without B4C at 450 °C and 750 °C, respectively, were analyzed by using Fourier transform infrared spectrum and high-resolution transmission electron microscopy technologies. It was found that B4C will retard extensive condensation and crosslinking reactions by reducing the amount of active oxygen obtained from thermally produced free radicals and increase secondary cracking reactions, resulting in increasing size of aromatic layer and anisotropic degree in coke structure, which eventually improves the coke quality. Full article
(This article belongs to the Special Issue Carbon-Based Materials)
Show Figures

Figure 1

12 pages, 4435 KiB  
Article
A Facile Method for the Generation of Fe3C Nanoparticle and Fe-Nx Active Site in Carbon Matrix to Achieve Good Oxygen Reduction Reaction Electrochemical Performances
by Yuzhe Wu, Yuntong Li, Conghui Yuan and Lizong Dai
Materials 2020, 13(21), 4779; https://doi.org/10.3390/ma13214779 - 26 Oct 2020
Cited by 4 | Viewed by 2042
Abstract
Introduction of both nitrogen and transition metal elements into the carbon materials has demonstrated to be a promising strategy to construct highly active electrode materials for energy shortage. In this work, through the coordination reaction between Fe3+ and 1,3,5–tris(4–aminophenyl)benzene, metallosupramolecular polymer precursors [...] Read more.
Introduction of both nitrogen and transition metal elements into the carbon materials has demonstrated to be a promising strategy to construct highly active electrode materials for energy shortage. In this work, through the coordination reaction between Fe3+ and 1,3,5–tris(4–aminophenyl)benzene, metallosupramolecular polymer precursors are designed for the preparation of carbon flakes co-doped with both Fe and N elements. The as-prepared carbon flakes display wrinkled edges and comprise Fe3C nanoparticle and active site of Fe–Nx. These carbon materials exhibit excellent electrocatalytic performance. Towards oxygen reduction reaction (ORR), the optimized sample has Eonset and Ehalf-wave of 0.93 V and 0.83 V in alkaline system, respectively, which are very close to that of Pt/C. This approach may offer a new way to high performance and low-cost electrochemical catalysts. Full article
(This article belongs to the Special Issue Carbon-Based Materials)
Show Figures

Graphical abstract

19 pages, 5964 KiB  
Article
On the Impact of Substrate Uniform Mechanical Tension on the Graphene Electronic Structure
by Konstantin P. Katin, Mikhail M. Maslov, Konstantin S. Krylov and Vadim D. Mur
Materials 2020, 13(20), 4683; https://doi.org/10.3390/ma13204683 - 21 Oct 2020
Cited by 4 | Viewed by 2263
Abstract
Employing density functional theory calculations, we obtain the possibility of fine-tuning the bandgap in graphene deposited on the hexagonal boron nitride and graphitic carbon nitride substrates. We found that the graphene sheet located on these substrates possesses the semiconducting gap, and uniform biaxial [...] Read more.
Employing density functional theory calculations, we obtain the possibility of fine-tuning the bandgap in graphene deposited on the hexagonal boron nitride and graphitic carbon nitride substrates. We found that the graphene sheet located on these substrates possesses the semiconducting gap, and uniform biaxial mechanical deformation could provide its smooth fitting. Moreover, mechanical tension offers the ability to control the Dirac velocity in deposited graphene. We analyze the resonant scattering of charge carriers in states with zero total angular momentum using the effective two-dimensional radial Dirac equation. In particular, the dependence of the critical impurity charge on the uniform deformation of graphene on the boron nitride substrate is shown. It turned out that, under uniform stretching/compression, the critical charge decreases/increases monotonically. The elastic scattering phases of a hole by a supercritical impurity are calculated. It is found that the model of a uniform charge distribution over the small radius sphere gives sharper resonance when compared to the case of the ball of the same radius. Overall, resonant scattering by the impurity with the nearly critical charge is similar to the scattering by the potential with a low-permeable barrier in nonrelativistic quantum theory. Full article
(This article belongs to the Special Issue Carbon-Based Materials)
Show Figures

Figure 1

12 pages, 2901 KiB  
Article
Surface Morphology of the Interface Junction of CVD Mosaic Single-Crystal Diamond
by Xiwei Wang, Peng Duan, Zhenzhong Cao, Changjiang Liu, Dufu Wang, Yan Peng, Xiangang Xu and Xiaobo Hu
Materials 2020, 13(1), 91; https://doi.org/10.3390/ma13010091 - 23 Dec 2019
Cited by 8 | Viewed by 3304
Abstract
The diamond mosaic grown on the single-crystal diamond substrates by the microwave plasma chemical vapor deposition (MPCVD) method has been studied. The average growth rate was about 16–17 μm/h during 48 hours’ growth. The surface morphologies of the as-grown diamond layer were observed. [...] Read more.
The diamond mosaic grown on the single-crystal diamond substrates by the microwave plasma chemical vapor deposition (MPCVD) method has been studied. The average growth rate was about 16–17 μm/h during 48 hours’ growth. The surface morphologies of the as-grown diamond layer were observed. It was found that the step flow was able to move across the substrates and cover the junction interface. Raman spectroscopic mapping in the central area of the junction revealed the high stress region movement across the junction interface from one substrate to the other for about 200–400 μm. High-resolution X-ray diffractometry (HRXRD) results proved that the surface step flow movement direction had nothing to do with the off-axis directions of the original substrates. It was found that the surface height difference of substrate was the main driving force for the step flow movement, junction combination and surface morphology changing. The mechanism of the mosaic interface junction combination and step flow transformation on the mosaic surface was proposed. Full article
(This article belongs to the Special Issue Carbon-Based Materials)
Show Figures

Figure 1

14 pages, 841 KiB  
Article
Modeling of One-Side Surface Modifications of Graphene
by Alexander V. Savin and Yuriy A. Kosevich
Materials 2019, 12(24), 4179; https://doi.org/10.3390/ma12244179 - 12 Dec 2019
Cited by 2 | Viewed by 2187
Abstract
We model, with the use of the force field method, the dependence of mechanical conformations of graphene sheets, located on flat substrates, on the density of unilateral (one-side) attachment of hydrogen, fluorine or chlorine atoms to them. It is shown that a chemically-modified [...] Read more.
We model, with the use of the force field method, the dependence of mechanical conformations of graphene sheets, located on flat substrates, on the density of unilateral (one-side) attachment of hydrogen, fluorine or chlorine atoms to them. It is shown that a chemically-modified graphene sheet can take four main forms on a flat substrate: the form of a flat sheet located parallel to the surface of the substrate, the form of convex sheet partially detached from the substrate with bent edges adjacent to the substrate, and the form of a single and double roll on the substrate. On the surface of crystalline graphite, the flat form of the sheet is lowest in energy for hydrogenation density p < 0.21 , fluorination density p < 0.20 , and chlorination density p < 0.16 . For higher attachment densities, the flat form of the graphene sheet becomes unstable. The surface of crystalline nickel has higher adsorption energy for graphene monolayer and the flat form of a chemically modified sheet on such a substrate is lowest in energy for hydrogenation density p < 0.47 , fluorination density p < 0.30 and chlorination density p < 0.21 . Full article
(This article belongs to the Special Issue Carbon-Based Materials)
Show Figures

Figure 1

11 pages, 10304 KiB  
Article
Homoepitaxy Growth of Single Crystal Diamond under 300 torr Pressure in the MPCVD System
by Xiwei Wang, Peng Duan, Zhenzhong Cao, Changjiang Liu, Dufu Wang, Yan Peng and Xiaobo Hu
Materials 2019, 12(23), 3953; https://doi.org/10.3390/ma12233953 - 28 Nov 2019
Cited by 15 | Viewed by 5378
Abstract
The high-quality single crystal diamond (SCD) grown in the Microwave Plasma Chemical Vapor Deposition (MPCVD) system was studied. The CVD deposition reaction occurred in a 300 torr high pressure environment on a (100) plane High Pressure High Temperature (HPHT) diamond type II a [...] Read more.
The high-quality single crystal diamond (SCD) grown in the Microwave Plasma Chemical Vapor Deposition (MPCVD) system was studied. The CVD deposition reaction occurred in a 300 torr high pressure environment on a (100) plane High Pressure High Temperature (HPHT) diamond type II a substrate. The relationships among the chamber pressure, substrate surface temperature, and system microwave power were investigated. The surface morphology evolution with a series of different concentrations of the gas mixture was observed. It was found that a single lateral crystal growth occurred on the substrate edge and a systemic step flow rotation from the [100] to the [110] orientation was exhibited on the surface. The Raman spectroscopy and High Resolution X-Ray Diffractometry (HRXRD) prove that the homoepitaxy part from the original HPHT substrate shows a higher quality than the lateral growth region. A crystal lattice visual structural analysis was applied to describe the step flow rotation that originated from the temperature driven concentration difference of the C2H2 ion charged particles on the SCD center and edge. Full article
(This article belongs to the Special Issue Carbon-Based Materials)
Show Figures

Graphical abstract

14 pages, 591 KiB  
Article
Chain Model for Carbon Nanotube Bundle under Plane Strain Conditions
by Elena A. Korznikova, Leysan Kh. Rysaeva, Alexander V. Savin, Elvira G. Soboleva, Evgenii G. Ekomasov, Marat A. Ilgamov and Sergey V. Dmitriev
Materials 2019, 12(23), 3951; https://doi.org/10.3390/ma12233951 - 28 Nov 2019
Cited by 24 | Viewed by 2282
Abstract
Carbon nanotubes (CNTs) have record high tensile strength and Young’s modulus, which makes them ideal for making super strong yarns, ropes, fillers for composites, solid lubricants, etc. The mechanical properties of CNT bundles have been addressed in a number of experimental and theoretical [...] Read more.
Carbon nanotubes (CNTs) have record high tensile strength and Young’s modulus, which makes them ideal for making super strong yarns, ropes, fillers for composites, solid lubricants, etc. The mechanical properties of CNT bundles have been addressed in a number of experimental and theoretical studies. The development of efficient computational methods for solving this problem is an important step in the design of new CNT-based materials. In the present study, an atomistic chain model is proposed to analyze the mechanical response of CNT bundles under plane strain conditions. The model takes into account the tensile and bending rigidity of the CNT wall, as well as the van der Waals interactions between walls. Due to the discrete character of the model, it is able to describe large curvature of the CNT wall and the fracture of the walls at very high pressures, where both of these problems are difficult to address in frame of continuum mechanics models. As an example, equilibrium structures of CNT crystal under biaxial, strain controlled loading are obtained and their thermal stability is analyzed. The obtained results agree well with previously reported data. In addition, a new equilibrium structure with four SNTs in a translational cell is reported. The model offered here can be applied with great efficiency to the analysis of the mechanical properties of CNT bundles composed of single-walled or multi-walled CNTs under plane strain conditions due to considerable reduction in the number of degrees of freedom. Full article
(This article belongs to the Special Issue Carbon-Based Materials)
Show Figures

Graphical abstract

13 pages, 1907 KiB  
Article
Effect of the Organic Functional Group on the Grafting Ability of Trialkoxysilanes onto Graphene Oxide: A Combined NMR, XRD, and ESR Study
by Massimo Calovi, Emanuela Callone, Riccardo Ceccato, Flavio Deflorian, Stefano Rossi and Sandra Dirè
Materials 2019, 12(23), 3828; https://doi.org/10.3390/ma12233828 - 21 Nov 2019
Cited by 16 | Viewed by 3069
Abstract
The functional properties displayed by graphene oxide (GO)-polymer nanocomposites are strongly affected by the dispersion ability of GO sheets in the polymeric matrix, which can be largely improved by functionalization with organosilanes. The grafting to GO of organosilanes with the general formula RSi(OCH [...] Read more.
The functional properties displayed by graphene oxide (GO)-polymer nanocomposites are strongly affected by the dispersion ability of GO sheets in the polymeric matrix, which can be largely improved by functionalization with organosilanes. The grafting to GO of organosilanes with the general formula RSi(OCH3)3 is generally explained by the condensation reactions of silanols with GO reactive groups. In this study, the influence of the organic group on the RSi(OCH3)3 grafting ability was analyzed in depth, taking into account the interactions of the R end chain group with GO oxidized groups. Model systems composed of commercial graphene oxide reacted with 3-aminopropyltrimethoxysilane (APTMS), 3-mercaptopropyltrimethoxysilane (MPTMS), and 3-methacryloxypropyltrimethoxysilane, (MaPTMS), respectively, were characterized by natural abundance 13C, 15N and 29Si solid state nuclear magnetic resonance (NMR), x-ray diffraction (XRD), and electron spin resonance (ESR). The silane organic tail significantly impacts the grafting, both in terms of the degree of functionalization and direct interaction with GO reactive sites. Both the NMR and XRD proved that this is particularly relevant for APTMS and to a lower extent for MPTMS. Moreover, the epoxy functional groups on the GO sheets appeared to be the preferential anchoring sites for the silane condensation reaction. The characterization approach was applied to the GO samples prepared by the nitric acid etching of graphene and functionalized with the same organosilanes, which were used as a filler in acrylic coatings obtained by cataphoresis, making it possible to correlate the structural properties and the corrosion protection ability of the layers. Full article
(This article belongs to the Special Issue Carbon-Based Materials)
Show Figures

Graphical abstract

11 pages, 5268 KiB  
Article
Thermoresistive Properties of Graphite Platelet Films Supported by Different Substrates
by Mariano Palomba, Gianfranco Carotenuto, Angela Longo, Andrea Sorrentino, Antonio Di Bartolomeo, Laura Iemmo, Francesca Urban, Filippo Giubileo, Gianni Barucca, Massimo Rovere, Alberto Tagliaferro, Giuseppina Ambrosone and Ubaldo Coscia
Materials 2019, 12(21), 3638; https://doi.org/10.3390/ma12213638 - 05 Nov 2019
Cited by 6 | Viewed by 2425
Abstract
Large-area graphitic films, produced by an advantageous technique based on spraying a graphite lacquer on glass and low-density polyethylene (LDPE) substrates were studied for their thermoresistive applications. The spray technique uniformly covered the surface of the substrate by graphite platelet (GP) unities, which [...] Read more.
Large-area graphitic films, produced by an advantageous technique based on spraying a graphite lacquer on glass and low-density polyethylene (LDPE) substrates were studied for their thermoresistive applications. The spray technique uniformly covered the surface of the substrate by graphite platelet (GP) unities, which have a tendency to align parallel to the interfacial plane. Transmission electron microscopy analysis showed that the deposited films were composed of overlapped graphite platelets of different thickness, ranging from a few tens to hundreds of graphene layers, and Raman measurements provided evidence for a good graphitic quality of the material. The GP films deposited on glass and LDPE substrates exhibited different thermoresistive properties during cooling–heating cycles in the −40 to +40 °C range. Indeed, negative values of the temperature coefficient of resistance, ranging from −4 × 10−4 to −7 × 10−4 °C−1 have been observed on glass substrates, while positive values varying between 4 × 10−3 and 8 × 10−3 °C−1 were measured when the films were supported by LDPE. These behaviors were attributed to the different thermal expansion coefficients of the substrates. The appreciable thermoresistive properties of the graphite platelet films on LDPE could be useful for plastic electronic applications. Full article
(This article belongs to the Special Issue Carbon-Based Materials)
Show Figures

Figure 1

25 pages, 7068 KiB  
Article
Effect of Doping Temperatures and Nitrogen Precursors on the Physicochemical, Optical, and Electrical Conductivity Properties of Nitrogen-Doped Reduced Graphene Oxide
by Nonjabulo P. D. Ngidi, Moses A. Ollengo and Vincent O. Nyamori
Materials 2019, 12(20), 3376; https://doi.org/10.3390/ma12203376 - 16 Oct 2019
Cited by 79 | Viewed by 4862
Abstract
The greatest challenge in graphene-based material synthesis is achieving large surface area of high conductivity. Thus, tuning physico-electrochemical properties of these materials is of paramount importance. An even greater problem is to obtain a desired dopant configuration which allows control over device sensitivity [...] Read more.
The greatest challenge in graphene-based material synthesis is achieving large surface area of high conductivity. Thus, tuning physico-electrochemical properties of these materials is of paramount importance. An even greater problem is to obtain a desired dopant configuration which allows control over device sensitivity and enhanced reproducibility. In this work, substitutional doping of graphene oxide (GO) with nitrogen atoms to induce lattice–structural modification of GO resulted in nitrogen-doped reduced graphene oxide (N-rGO). The effect of doping temperatures and various nitrogen precursors on the physicochemical, optical, and conductivity properties of N-rGO is hereby reported. This was achieved by thermal treating GO with different nitrogen precursors at various doping temperatures. The lowest doping temperature (600 °C) resulted in less thermally stable N-rGO, yet with higher porosity, while the highest doping temperature (800 °C) produced the opposite results. The choice of nitrogen precursors had a significant impact on the atomic percentage of nitrogen in N-rGO. Nitrogen-rich precursor, 4-nitro-ο-phenylenediamine, provided N-rGO with favorable physicochemical properties (larger surface area of 154.02 m2 g−1) with an enhanced electrical conductivity (0.133 S cm−1) property, making it more useful in energy storage devices. Thus, by adjusting the doping temperatures and nitrogen precursors, one can tailor various properties of N-rGO. Full article
(This article belongs to the Special Issue Carbon-Based Materials)
Show Figures

Graphical abstract

Review

Jump to: Research

17 pages, 4287 KiB  
Review
Synthesis of Vertically Oriented Graphene Sheets or Carbon Nanowalls—Review and Challenges
by Alenka Vesel, Rok Zaplotnik, Gregor Primc and Miran Mozetič
Materials 2019, 12(18), 2968; https://doi.org/10.3390/ma12182968 - 12 Sep 2019
Cited by 39 | Viewed by 4041
Abstract
The paper presents a review on the current methods for deposition of vertically oriented multilayer graphene sheets (often called carbon nanowalls—CNWs) on solid substrates. Thin films of CNWs are among the most promising materials for future applications in capacitors, batteries, electrochemical devices, and [...] Read more.
The paper presents a review on the current methods for deposition of vertically oriented multilayer graphene sheets (often called carbon nanowalls—CNWs) on solid substrates. Thin films of CNWs are among the most promising materials for future applications in capacitors, batteries, electrochemical devices, and photovoltaics, but their application is currently limited by slow deposition rates and difficulties in providing materials of a desired structure and morphology. The review paper analyzes results obtained by various groups and draws correlations between the reported experimental conditions and obtained results. Challenges in this scientific field are presented and technological problems stressed. The key scientific challenge is providing the growth rate as well as morphological and structural properties of CNWs thin films versus plasma parameters, in particular versus the fluxes of reactive plasma species onto the substrate surface. The technological challenge is upgrading of deposition techniques to large surfaces and fast deposition rates, and development of a system for deposition of CNWs in the continuous mode. Full article
(This article belongs to the Special Issue Carbon-Based Materials)
Show Figures

Graphical abstract

Back to TopTop