The enthalpies of formation of carbon nanomaterials as a key factor for understanding their structural features

2017 ◽  
Vol 19 (3) ◽  
pp. 2269-2275 ◽  
Author(s):  
E. V. Suslova ◽  
S. V. Savilov ◽  
J. Ni ◽  
V. V. Lunin ◽  
S. M. Aldoshin

Carbon nanomaterials (CNMs), such as carbon nanotubes (CNTs), carbon nanoflakes (CNFs) and their N-doped derivatives, show sufficient correlations between structure, composition and properties.

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Jong Won Choi ◽  
Seul Ki Youn ◽  
Hyung Gyu Park

This paper describes the morphology of carbon nanomaterials such as carbon nanotube (CNT), graphene, and their hybrid structure under various operating conditions during a one-step synthesisviaplasma-enhanced chemical vapor deposition (PECVD). We focus on the synthetic aspects of carbon hybrid material composed of heteroepitaxially grown graphene on top of a vertical array of carbon nanotubes, called carbon micronymphaea. We characterize the structural features of this unique nanocomposite by uses of electron microscopy and micro-Raman spectroscopy. We observe carbon nanofibers, poorly aligned and well-aligned vertical arrays of CNT sequentially as the growth temperature increases, while we always discover the carbon hybrids, called carbon micronymphaea, at specific cooling rate of 15°C/s, which is optimal for the carbon precipitation from the Ni nanoparticles in this study. We expect one-pot synthesized graphene-on-nanotube hybrid structure poses great potential for applications that demand ultrahigh surface-to-volume ratios with intact graphitic nature and directional electronic and thermal transports.


2011 ◽  
Vol 2011 ◽  
pp. 1-21 ◽  
Author(s):  
Ali Mostofizadeh ◽  
Yanwei Li ◽  
Bo Song ◽  
Yudong Huang

In recent years, many theoretical and experimental studies have been carried out to develop one of the most interesting aspects of the science and nanotechnology which is called carbon-related nanomaterials. The goal of this paper is to provide a review of some of the most exciting and important developments in the synthesis, properties, and applications of low-dimensional carbon nanomaterials. Carbon nanomaterials are formed in various structural features using several different processing methods. The synthesis techniques used to produce specific kinds of low-dimensional carbon nanomaterials such as zero-dimensional carbon nanomaterials (including fullerene, carbon-encapsulated metal nanoparticles, nanodiamond, and onion-like carbons), one-dimensional carbon nanomaterials (including carbon nanofibers and carbon nanotubes), and two-dimensional carbon nanomaterials (including graphene and carbon nanowalls) are discussed in this paper. Subsequently, the paper deals with an overview of the properties of the mainly important products as well as some important applications and the future outlooks of these advanced nanomaterials.


Nanomaterials ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1882
Author(s):  
Jin Ah Lee ◽  
Won Jun Lee ◽  
Joonwon Lim ◽  
Sang Ouk Kim

Metal oxide nanoparticles supported on heteroatom-doped graphitic surfaces have been pursued for several decades for a wide spectrum of applications. Despite extensive research on functional metal oxide nanoparticle/doped carbon nanomaterial hybrids, the role of the heteroatom dopant in the hybridization process of doped carbon nanomaterials has been overlooked. Here, the direct growth of MnOx and RuOx nanoparticles in nitrogen (N)-doped sites of carbon nanotubes (NCNTs) is presented. The quaternary nitrogen (NQ) sites of CNTs actively participate in the nucleation and growth of the metal nanoparticles. The evenly distributed NQ nucleation sites mediate the generation of uniformly dispersed <10 nm diameter MnOx and RuOx nanoparticles, directly decorated on NCNT surfaces. The electrochemical performance of the resultant hybridized materials was evaluated using cyclic voltammetry. This novel hybridization method using the dopant-mediated nucleation and growth of metal oxides suggests ways that heteroatom dopants can be utilized to optimize the structure, interface and corresponding properties of graphitic carbon-based hybrid materials.


Water ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 1426
Author(s):  
Zhanhua Ji ◽  
Dengyu Li

The stability of carbon nanotubes (CNTs) suspension is a key factor in determining their transport, fate, and toxicity in an aquatic environment, which is significantly influenced by CNTs’ nature and water chemistry. Macromolecular dissolved organic matter (DOM) is reported to influence the stability of CNTs aggregation. However, little is known on small polar dissolved organic compound’s effects on CNTs aggregation. Nitrobenzene was selected to investigate its interaction with three different functionalized multiwalled CNTs (MWCNTs). Both the stability of CNTs aggregation and sorption hysteresis were affected by the initial concentration of nitrobenzene and the surface functionalization coverage of MWCNTs. At the initial concentration below 580 mg/L, the thermodynamic index of irreversibility (TII) and turbidity of CNTs suspension had the same tendency, indicating that the underlying mechanism is closely related. A conceptual adsorption–desorption model was proposed to further explain the relationship between the sorption hysteresis and stability of MWCNTs suspension under different initial concentrations of nitrobenzene. This provided data support to further clarify the environmental behaviors and risks of CNTs.


2021 ◽  
Author(s):  
Hakim AL Garalleh

Abstract Carbon nanomaterials have received increasing attention in drug delivery applications because of their distinct properties and structures, including large surface areas, high conductivity, low solubility in aqueous media, unique chemical functionalities and stability at the nano-scale size. Particularly, they have been used as nano-carriers and mediators for anticancer drugs such as, combination with Cisplatin, Camptothecin and Doxorubicin. Cancer has become the most challenging disease because its sophisticated therapy and classified as one of the top killers according to the World health organization records. The aim of the current work is to study and investigate the mechanism of combination between single-walled carbon nanotubes (SWCNTs) and the fullerene derivatives (C N -[OH] β ) as mediators, and anticancer drugs for photodynamic therapy directly to destroy the infected cells without damaging the normal ones. Here, we obtain a bio-medical model to determine the efficiency of usefulness of Doxorubicin (DOX) as an antitumor agent conjugated with SWCNTs with variant radii r and fullerene derivative (C N -[OH] β ). The two sub-models are obtained mathematically to evaluate the potential energy arising from the DOX-SWCNT and DOX-(C N -[OH] β ) interactions. DOX modelled as two-connected spheres, small and large, each interacting with different SWCNTs (variant radii r ) and fullerene derivatives C N -[OH] β , forming based on the number of carbon atoms (N) and the number of Hydroxide molecules (OH) ( β ), respectively.


2021 ◽  
Author(s):  
Sunil Kumar ◽  
Abhay Nanda Srivastva

Carbon nanomaterials (CNMs), especially carbon nanotubes and graphene, have been attracting tremendous attention in environmental analysis for rapid and cost effective detection of various analytes by electrochemical sensing. CNMs can increase the electrode effective area, enhance the electron transfer rate between the electrode and analytes, and/or act as catalysts to increase the efficiency of electrochemical reaction, detection, adsorption and removal are of great significance. Various carbon nanomaterials including carbon nanotubes, graphene, mesoporous carbon, carbon dots exhibited high adsorption and detection capacity. Carbon and its derivatives possess excellent electro catalytic properties for the modified sensors, electrochemical methods usually based on anodic stripping voltammetry at some modified carbon electrodes. Metal electrode detection sensitivity is enhanced through surface modification of working electrode (GCE). Heavy metals have the defined redox potential. A remarkable deal of efficiency with the electrochemical sensors can be succeeded by layering the surface of the working electrode with film of active electro-catalytic species. Usually, electro catalysts used for fabrication of sensors are surfactants, nano-materials, polymers, carbon-based materials, organic ligands and biomaterials.


2010 ◽  
Vol 2010 ◽  
pp. 1-5 ◽  
Author(s):  
Leilei Tian ◽  
Xin Wang ◽  
Li Cao ◽  
Mohammed J. Meziani ◽  
Chang Yi Kong ◽  
...  

Arc-discharge has been widely used in the bulk production of various carbon nanomaterials, especially for structurally more robust single-walled carbon nanotubes. In this paper, the same bulk-production technique was applied to the synthesis of significantly13C-enriched graphitic materials, from which graphene oxides similarly enriched with13C were prepared and characterized. The results demonstrate that arc-discharge is a convenient method to produce bulk quantities of13C-enriched graphene materials from relatively less expensive precursors (largely amorphous13C powders).


Author(s):  
Rafael Vargas-Bernal

There is enormous interest in carbon nanomaterials, due to their exceptional physical properties, from the perspective of science and engineering of materials applied to the electronics industry. Until now, significant progress has been made towards understanding the mechanisms of electrical conductivity of carbon nanotubes and graphene. However, scientists around the world even today continue studying these mechanisms, for exploiting them fully in different electronic applications with a high technological impact. This article discusses the mechanisms of electrical conductivity of both nanomaterials, analyzes the present implications, and projects its importance for future generations of electronic devices. In particular, it is important to note that different mechanisms may be identified when these nanomaterials are used individually, when they are incorporated as fillers in composite materials or hybrid materials, or even when they are doped or functionalized. Finally, other electrical variables with important role in electrical conductivity of these materials are also explored.


Author(s):  
Rafael Vargas-Bernal

There is enormous interest in carbon nanomaterials due to their exceptional physical properties, from the perspective of science and engineering of materials applied to the electronics industry. Significant progress has been made towards understanding the mechanisms of electrical conductivity of carbon nanotubes and graphene. However, scientists around the world continue studying these mechanisms to exploit them fully in different electronic applications with a high technological impact. This chapter discusses the mechanisms of electrical conductivity of both nanomaterials, analyzes the present implications, and projects its importance for future generations of electronic devices. In particular, it is important to note that different mechanisms may be identified when these nanomaterials are used individually, when they are incorporated as fillers in composite materials or hybrid materials, or even when they are doped or functionalized. Finally, other electrical variables with important role in electrical conductivity of these materials are also explored.


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