Carbon Nanoclusters Research Articles

Toxic gas removal using transition metal-decorated Cyclo[18]carbon: A first principles prevision

Carbon monoxide (CO), nitric oxide (NO), and ammonia (NH3) are highly toxic gases that are hazardous to human health and the environment. This study dives into the examination of interaction mechanism between transition metal-decorated Cyclo[18]carbon or C18TM (TM = Ni, Pd, Pt) nanoclusters and aforementioned gas molecules. The analysis of structural, electronic, topological, spectroscopic, and sensing properties, uncovers significant findings. The computed adsorption energies exhibit highly negative values. Notably, a substantial sensing response is observed, particularly in the context of NO adsorption over C18Ni and CO adsorption over C18Pd nanoclusters. Employing the Quantum Theory of Atoms in Molecules (QTAIM), we discern the strength of each interaction. Raman spectra analyses provide additional details regarding the vibrational aspects of these interactions. Our Non-Covalent Interaction (NCI) study effectively elucidates the mechanisms underlying van der Waals interactions. Evidently, the longer recovery times observed in our calculations, owing to the highly negative adsorption energies with −2.31 eV being the most negative value for CO molecule over C18Pt nanocluster and −1.09 eV value for NO over C18Pd being the least, suggest that C18TM nanoclusters are better suited for gas removal applications rather than rapid-response sensors.

Carbon contamination of elemental beta-boron promoted a stable boron carbide by spark plasma sintering

The effect of carbon contamination on the elemental beta boron (β-B) from the graphite components of spark plasma sintering (SPS) was investigated. The X-ray diffraction, analytical electron microscopy (AEM) and Raman spectroscopy witnessed boron carbide (B13+xC2-x where x=0.05–0.35), when SPS temperature was above 1750 °C. The degree of carbon contamination became severe with increasing SPS temperature to 1800 °C and 1850 °C and formed a single-phase rhombohedral boron carbide with about 12 wt% of carbon. Our observations indicate that the carbon gets kinetically trapped into β-B to form boron carbide with a primitive unit cell consisting mainly of icosahedral B11C and three-atom chain of CBB configurations. After 6 months of natural aging, it has been revealed that boron carbide formed at and below sintering temperatures of 1800 °C is not a thermodynamically stable phase, and transformed reversibly to β-B structure. X-ray photoelectron spectroscopy ascertained that there are no longer B-C bonds and the existence of more CC bonds in a 6 months aged specimen, suggesting carbon is no longer strongly bonded to boron, but precipitates as graphitic structure. Further examination using atom probe tomography and AEM confirmed the existence of carbon nanoclusters within grains and high concentration of carbon segregating onto grain boundaries. The phase transformation of boron carbide to mostly boron resulted in a significant loss of hardness and modulus in a bulk SPS specimen. This study underscores the importance of solid solution and local bonding environment in icosahedral boron-rich solids for phase stability and sustained properties.

Nonmetallic Se/N Co‐Doped Amorphous Carbon Anode Collaborates to Realize Ultra‐High Capacity and Fast Potassium Storage for Potassium Dual‐Ion Batteries

AbstractHeteroatom doping in carbon‐based anode materials is crucial to improve their capacity and promoting the practical application of low‐cost potassium‐ion batteries (KIBs). Herein, the selenium/nitrogen co‐doped amorphous carbon nanocluster (SeN‐ACN) anodes exhibit an ultra‐high reversible capacity of 621 mAh g−1 at 0.75 C (225 mA g−1) and a capacity retention of 93% after 2000 cycles at 5 C, which represent a remarkable achievement in potassium storage in nonmetallic doped carbon materials. This is attributed to the synergistic effects of Se/N co‐doping and their anchoring effects on potassium ions. As a proof of concept, a potassium‐based dual‐ion battery (K‐DIB), which consists of a SeN‐ACN anode and low‐cost graphite cathode, demonstrates a high reversible capacity of 118 mAh g−1 at 150 mA g−1 with a high cut‐off voltage of 5.2 V. Moreover, it presents excellent long‐term cycling performance, with 70% capacity retention after 500 cycles, among the best reported results of K‐DIBs.

Electron-vibrational renormalization in fullerenes through ab initio and machine learning methods.

The effect of nuclear vibrations on the electronic eigenvalues and the HOMO-LUMO gap is known for several kinds of carbon-based materials, like diamond, diamondoids, carbon nanoclusters, carbon nanotubes and others, like hydrogen-terminated oligoynes and polyyne. However, it has not been widely analysed in another remarkable kind which presents both theoretical and technological interest: fullerenes. In this article we present the study of the HOMO, LUMO and gap renormalizations due to zero-point motion of a relatively large number (163) of fullerenes and fullerene derivatives. We have calculated this renormalization using density-functional theory with the frozen-phonon method, finding that it is non-negligible (above 0.1 eV) for systems with relevant technological applications in photovoltaics and that the strength of the renormalization increases with the size of the gap. In addition, we have applied machine learning methods for classification and regression of the renormalizations, finding that they can be approximately predicted using the output of a computationally cheap ground state calculation. Our conclusions are supported by recent research in other systems.

Möbius carbon nanobelts interacting with heavy metal nanoclusters.

The interaction between carbon nanostructures and heavy metal clusters is of great interest due to their potential applications as sensors and filters to remove the former from environment. In this work, we investigated the interaction between two types of carbon nanobelts (Möbius-type nanobelt and simple nanobelt) and nickel, cadmium, and lead nanoclusters. Our aim was to determine how both systems interact which would shed light on the potential applications of the carbon nanostructures as pollutant removal and detecting devices. To investigate the interaction between carbon nanostructures and heavy metal nanoclusters, we utilized the semiempirical tight binding framework provided by xTB software with the GFN2-xTB Hamiltonian. We performed calculations to determine the best interaction site, lowest energy geometries, complexes stability (using molecular dynamics at 298K), binding energy, and electronic properties. We also carried out a topological study to investigate the nature and intensity of the bonds formed between the metal nanoclusters and the nanobelts. Our results demonstrate that heavy metal nanoclusters have a favorable binding affinity towards both nanobelts, with the Möbius-type nanobelt having a stronger interaction. Additionally, our calculations reveal that the nickel nanocluster has the lowest binding energy, displaying the greatest charge transfer with the nanobelts, which was nearly twice that of the cadmium and lead nanoclusters. Our combined results lead to the conclusion that the nickel nanoclusters are chemisorbed, whereas cadmium and lead nanoclusters are physisorbed in both nanobelts. These findings have significant implications for the development of sensor and filtering devices based on carbon and heavy metal nanoclusters.

Cluster structure of ultrahard fullerite revealed by Raman spectroscopy

We have discovered Raman peculiarities of sp3-bonded carbon nanoclusters forming ultrahard fullerite synthesized at pressure up to 85 GPa. The nanoclusters differ in the values of bulk modulus B0 ranging from 580 to 730 GPa. We found that the Raman frequency, corresponding to the C-C stretching mode of the nanoclusters, varies linearly from 1485 to 1640 cm−1, depending on the excitation wavelength used, which ranges from 785 nm to 257 nm. In particular, the nanoclusters with higher B0 have a higher Raman frequency. We also observed a resonant Raman spectrum when excited at a wavelength of 1064 nm. This showed a plateau from 1400 to 1720 cm−1, covering all Raman band positions of the nanoclusters from 1485 to 1640 cm−1. In addition, two Raman bands at 1285 and 1600 cm−1 appear at the resonance. The presence of several types of carbon sp3-bonded nanoclusters is confirmed by high-resolution transmission electron microscopy. Using moment tensor potentials, a class of machine learning interatomic potentials, we calculated the phonon density of states of the nanoclusters formed during the 3D polymerization of C60. The presence of high frequency modes in the resonant Raman spectra suggests the existence of bonds with force constants higher than those in a single crystal diamond. In addition, we observed a stiffening effect when analyzing the dependence of the mechanical stiffness on the cluster size, with smaller clusters exhibiting a more rigid structure.

Modeling and characterization of the nucleation and growth of carbon nanostructures in physical synthesis

Carbon nanostructures formed through physical synthesis come in a variety of sizes and shapes. With the end goal of rationalizing synthetic pathways of carbon nanostructures as a function of tunable parameters in the synthesis, we investigate how the initial density and quench rate influence the morphology of carbon nanostructures obtained from the cooling of a gas of atomic carbon by molecular dynamics simulations. For the structural analysis, we combine classical order parameters with a data-driven approach based on local density descriptors and kernel similarity measurements. Aided by this complementary set of tools, we describe in detail the formation of carbon nanostructures from the gas phase. Their formation proceeds through the nucleation of small liquid carbon nanoclusters followed by growth into unique objects. We find that ordered structures can only be obtained at certain quenching rates and that among those, fullerene-like particles are favored at intermediate densities while nanotubes-like structures require higher initial densities. © XXXX CEA. Elsevier

Dual-Exciting Central Carbon Nanoclusters for the Dual-Channel Detection of Hemin

Constructing optical nanoprobes with superior performance is highly desirable for sensitive and accurate assays. Herein, we develop a facile room-temperature strategy for the fabrication of green emissive carbon nanoclusters (CNCs) with dual-exciting centers for the dual-channel sensing of hemin. The formation of the CNCs is attributed to the crosslinking polymerization of the precursors driven by the Schiff base reaction between ethylenediamine and 2,3-dichloro-5,6-dicyano-1,4-benzoquinone. Most importantly, the proposed CNCs have a unique excitation-independent green emission (518 nm) with two excitation centers at 260 nm (channel 1) and 410 nm (channel 2). The dual-exciting central emission can serve as dual-channel fluorescence (FL) signals for highly sensitive and reliable detection of hemin based on the inner filter effect. Because of the great spectral overlap difference between the absorption spectrum of hemin and the excitation lights of the CNCs in the two channels, hemin has a different quenching effect on FL emission from different channels. The dual-channel signals of the CNCs can detect hemin in the range of 0.075–10 μM (channel 1) and 0.25–10 μM (channel 2), respectively. These findings not only offer new guidance for the facile synthesis of dual-exciting central CNCs but also establish a reliable sensing platform for the analysis of hemin in complex matrixes.

Carbon Nanocluster-Mediated Nanoblending Assembly for Binder-Free Energy Storage Electrodes with High Capacities and Enhanced Charge Transfer Kinetics.

The effective spatial distribution and arrangement of electrochemically active and conductive components within metal oxide nanoparticle (MO NP)-based electrodes significantly impact their energy storage performance. Unfortunately, conventional electrode preparation processes have much difficulty addressing this issue. Herein, this work demonstrates that a unique nanoblending assembly based on favorable and direct interfacial interactions between high-energy MO NPs and interface-modified carbon nanoclusters (CNs) notably enhances the capacities and charge transfer kinetics of binder-free electrodes in lithium-ion batteries (LIBs). For this study, carboxylic acid (COOH)-functionalized carbon nanoclusters (CCNs) are consecutively assembled with bulky ligand-stabilized MO NPs through ligand-exchange-induced multidentate binding between the COOH groups of CCNs and the surface of NPs. This nanoblending assembly homogeneously distributes conductive CCNs within densely packed MO NP arrays without insulating organics (i.e., polymeric binders and/or ligands) and prevents the aggregation/segregation of electrode components, thus markedly reducing contact resistance between neighboring NPs. Furthermore, when these CCN-mediated MO NP electrodes are formed on highly porous fibril-type current collectors (FCCs) for LIB electrodes, they deliver outstanding areal performance, which can be further improved through simple multistacking. The findings provide a basis for better understanding the relationship between interfacial interaction/structures and charge transfer processes and for developing high-performance energy storage electrodes.

YbSiOC ceramics with a multidimensional nanostructure for high-efficiency electromagnetic wave absorption

The controllable microstructure of a material plays a vital role in its electromagnetic (EM) wave absorption performance. Herein, a multidimensional nanostructure including a matchstick-like SiCnws network structure with a carbon nanocluster was grown in-situ in a porous Yb2Si2O7 ceramic by precursor infiltration and pyrolysis (PIP) to prepare YbSiOC ceramics. As the number of PIPs increased, the absorber (SiCnws and carbon) content increased to construct a multidimensional nanostructure, which also promoted conductivity loss, interfacial polarization loss and dipole polarization loss. The results showed that the YbSiOC ceramics (with an absorber content of 28.2 wt%) achieved a minimum reflection loss (RLmin) of − 50.0 dB at 9.39 GHz with 2.7 mm, and the effective absorption bandwidth (EAB) reached 4.2 GHz (in the X band) as the thickness increased from 2.1 to 3.5 mm. To conclude, the matchstick-like SiCnws and carbon nanoclusters build a multidimensional network structure that is capable of multiple reflections and scattering of EM waves in YbSiOC ceramics. This work proposes a feasible method to design rare earth silicates with EM absorbing performance, and it is expected to have durable applications in water-vapor environments.

Boron-enriched rice-like homologous carbon nanoclusters with a 51.5% photoluminescent quantum yield for highly sensitive determination of endogenous hydroxyl radicals in living cells.

Exploring the ultrahigh quantum efficiency of a carbon-based probe via a green and simple technique, and utilisation of its sensing ability for highly bioactive molecule detection is still highly challenging. Herein, we prepared a novel boron-enriched rice-like homologous carbon nanoclusters (BRCNs) with an ultrahigh quantum efficiency of ∼51.5% by introduction of a conjugated structure attached to the CN bond and an electron-withdrawing boron active centre. Unexpectedly, the BRCNs obtained showed a stable dispersion of rice-like carbon nanograins, composed of small carbon dot assembled nanoclusters with an average diameter size of ∼30 nm, and containing boron units of ∼24.68 at%. What's exciting is that the BRCNs obtained exhibited an "on-off-on" three-state emission with the addition of an hydroxyl radical (OH˙) and its antioxidants. Thus, two distinctive fluorescent responses for OH˙ and antioxidants based on the BRCN probe had been developed, and the mechanism has been determined using TEM, XPS, FT-IR, FL, UV-vis spectrophotometry, UPS and fluorescent lifetimes. The OH˙, generated from the Fenton's reagent, preferentially attack the electron-deficient vacancy p orbit of the boron atom in the surface of the BRCNs, which results in the boron atom being easily substituted/attacked by OH˙, and leading to spontaneous aggregation induced quenching (AIQ) due to the existence of a strong intermolecular hydrogen bond between denatured BRCNs. Furthermore, the proposed method was also successfully applied to monitor endogenous OH˙ generation in HeLa cells by confocal imaging, which could be used for elucidating OH˙-induced oxidative damage to biological tissues and proteins.

In Ukrainian

Metal composites modified with various heteroatoms, such as N, B, Si, are used to obtain matrix composites with specified parameters with the strongest adhesive-cohesive bonds between metal atoms and a carbon nanoparticle. Such carbon nanoparticles functionalized with heteroatoms are promising for many metal composites. One of the interesting and promising metals as a matrix for such research work is iron. To predict the specifics of the interaction of iron with the surface of carbon nanomaterials supplemented with heteroatoms of different chemical structure, it is advisable to model such processes using quantum chemistry methods. The aim of the work was to find out the effect of temperature on the chemical interaction of iron clusters with native, boron-, silicon-, and nitrogen-containing graphene-like planes (GLP). The results of the calculations show that the highest value of the energy effect of the chemical interaction for the native graphene-like plane is +204.3 kJ/mol, in the case of calculations both by the B3LYP/6-31G(d,p) method and by the MP2/6-31G(d, p) (+370.7 kJ/mol). The lower value of the energy effect is found in the presence of nitrogen atoms in the composition of the graphene-like plane. This value is even lower for the interaction of iron dimers with a silicon-containing carbon nanocluster. The lowest values of the energy effect, calculated by both methods, are characteristic of the boron-containing graphene-like plane. In particular, for the B3LYP/6-31G(d,p) method, the value of the energy effect of the reaction is ‑210.5 kJ/mol, and for the MP2/6-31G(d,p) method this value is +16.6 kJ/mol. The presence of boron atoms in the composition of the nanocarbon matrix best contributes to the interaction with the iron nanocluster, regardless of the chosen research method. The dependence curves of the Gibbs free energy of the interaction of iron dimers with a graphene-like plane and its derivatives in all cases qualitatively correlate with similar energy effects. In addition, in all cases, the values of the Gibbs free energy increase with increasing temperature.

Advances in Carbon Nanomaterial–Clay Nanocomposites for Diverse Applications

Clay materials are widely used in sheet-type platforms with peculiar characteristics and diverse applications. However, due to some disadvantages—such as weak mechanical strength and low reactivity—they are often subjected to modifications. Such tuning leads to better output than pure clay materials. This review describes some of the clay hybrids in the form of nanocomposites with carbon nanomaterials. Generally, graphene oxide or its derivatives—such as reduced graphene oxide, carbon nanotubes, carbon dots, carbon nanoclusters, and polymeric components—have been utilized so far to make efficient clay composites that have applications such as catalysis, wastewater treatment for toxin removal, cargo delivery, stimulus-responsive advanced tools, optoelectronics, mechanically stable films for filtration, etc. It is interesting to note that nearly all of these applications tend to show the efficacy of modified clay nanocomposites as being significantly greater than that of pure clay, especially in terms of mechanical strength, loading capacity, increased surface area, and tunable functionality. According to the literature, the evidence proves the beneficial effects of these clay nanocomposites with carbon nanomaterials.

Discrimination of different amorphous carbon by low fluence laser irradiation

Carbon thin film depositions were carried out with femtosecond laser ablation from two different sp 2 -bonded carbon targets, namely highly oriented pyrolytic graphite (HOPG) and glassy carbon (GC). Femtosecond laser deposition is generally known as a means of generating nanoparticles. To our knowledge, Raman spectroscopy is not able to directly discriminate the as-deposited amorphous films which may contain different sp 2 carbon nanoclusters while still showing similar Raman spectra. Moreover, these films are not easily distinguishable from each other by transmission electron microscopy observation due to their amorphous structure. In this work, we show that controlled laser irradiation of thin films at low fluence is an interesting approach to reveal the existence of structural differences for amorphous films deposited from sp 2 carbon targets (HOPG and GC).

Carbon and Silicon Nano-Clusters as Anode Electrodes of Metal Ion Batteries

Carbon and Silicon Nano-Clusters as Anode Electrodes of Metal Ion Batteries

Nanoparticle-based single molecule fluorescent probes.

Single molecule fluorescent probes have attracted considerable attention due to their ultimate sensitivity, fast response, low sample consumption, and high signal-to-noise ratio. Nanoparticles with outstanding optical properties make them perfect candidates for probes in the application of single molecule detection. In this review, we focus on various kinds of nanoparticles acting as single molecule fluorescent probes, including quantum dots, upconverting fluorescent nanoparticles, carbon dots, single-wall carbon nanotubes, fluorescent nanodiamonds, polymeric nanoparticles, nanoclusters, and metallic nanoparticles. Optical properties of various nanoparticles and their recent application in single molecule fluorescent probes are explored. How nanoparticles boost the sensitivity of detection is emphasized in combination with different sensing strategies. Future trends of nanoparticles in single molecule detection are also discussed. We hope that this review can provide practical guidance for researchers who work on nanoparticle-based single molecule fluorescent probes.

In-situ encapsulation of oil soluble carbon nanoclusters in ZIF-8 and applied as bifunctional recyclable stable sensing material of nitrofurazone and lysine and fluorescent ink

Metal-organic frameworks (MOFs) are porous materials consisting of organic ligands and metal ions/clusters through coordinate bonds, which have wide applications in the research fields such as sensing, catalysis, and adsorbents. On the other hand, as an emerging carbon nanomaterial with low toxicity and chemical inertia, carbon nanoclusters (CNCs) have received a lot of research interest. In this work, an oil soluble CNC was introduced into Zeolitic imidazolate framework-8 (ZIF-8) through in-situ encapsulation strategy to form hybrid material CNCs@ZIF-8 (1). 1 has been characterized by PXRD, FT-IR, Transmission electron microscopy (TEM) and photo-luminescent characterizations. Strong fluorescence emission at 450 nm for 1 can be observed when excited at 380 nm. Remarkably, the structure and fluorescence emission of 1 can maintain unchanged after soaking in different DMA, DMF, ethyl alcohol solvent and adding different targeted objects. Photo-luminescent studies show that 1 can be used as highly sensitive and selective “turn-off” fluorescent probe for antibiotic nitrofurazone (Ksv: 2.26 × 105 M−1 and detection limit: 0.0229 µM). On the other hand, 1 shows highly sensitive and selective “turn-on” response to lysine (KBH: 1.99 × 106 M−1 and detection limit: 0.0096 µM). Additionally 1 also exhibits good recyclable detection performance, after four numbers of detection cycles, the detection efficiency of nitrofurazone and lysine still can reach 93.86% and 88.82%, respectively. Further, in the UV-vis light excited at 365 nm, the fluorescent ink based on 1 with the addition of lysine can be observed in naked eye. As a result, 1 could be applied as a bifunctional recyclable stable sensing material for highly sensitive detection of nitrofurazone and lysine and fluorescent ink using 1 with the addition of lysine.

Luminescent Carbon Nanoclusters for Sensitive Detection of Ascorbic Acid and Fluorescent Printing

Luminescent Carbon Nanoclusters for Sensitive Detection of Ascorbic Acid and Fluorescent Printing

Development of Novel Analysis and Characterization Methods Utilizing Reaction Dynamics in a Separation Capillary

Electrophoretic migration of an analyte in capillary electrophoresis (CE) reflects reaction dynamics of the analyte in solution. In affinity CE, an analyte of interest interacts with a modifier added in the separation buffer in fast equilibrium, and effective electrophoretic mobility of the analyte is contributed from its equilibrium species. Precise measurement of effective electrophoretic mobility allows analyzing the equilibrium. Analysis of equilibria under CE separation possesses several advantages against traditional analyses in homogeneous solution; coexisting substances including impurities and kinetically generated substances are resolved by CE from the equilibrium species of interest. Characteristics of the CE analysis have been applied to analyses of acid-base equilibria of degradable substances and ion-association equilibria in an aqueous solution. Since CE is operated in an open-tubular capillary, it is also suitable for the characterization of carbon nanoclusters such as graphene and carbon nanotube, and measurement of effective electrophoretic mobility helps characterization of nanoclusters. A novel analysis technique of capillary electrophoresis/dynamic frontal analysis (CE/DFA) has also been proposed for the analysis of such reactions as involving equilibria and kinetic reactions. In CE/DFA, kinetically generated product is continuously resolved from the equilibrium species, and a plateau signal would be detected when the reaction rate is constant. Michaelis-Menten constants have successfully been determined through the plateau height by CE/DFA. In this review, analysis and characterization methods utilizing reaction dynamics in a separation capillary are summarized.

Accelerating the prediction of large carbon clusters via structure search: Evaluation of machine-learning and classical potentials

From as small as single carbon dimers up to giant fullerenes or amorphous nanometer-sized particles, the large family of carbon nanoclusters holds a complex structural variability that increases with cluster size. Capturing this variability and predicting stable allotropes remains a challenging modelling task, crucial to advance technological applications of these materials. While small cluster sizes are traditionally investigated with first-principles methods, a comprehensive study spanning larger sizes calls for a computationally efficient alternative. Here, we combine the stochastic ab initio random structure search algorithm (AIRSS) with geometry optimisations based on interatomic potentials to systematically predict the structure of carbon clusters spanning a wide range of sizes. We first test the transferability and predictive capability of seven widely used carbon potentials, including classical and machine-learning potentials. Results are compared against an analogous cluster dataset generated via AIRSS combined with density functional theory optimizations. The best performing potential, GAP-20, is then employed to predict larger clusters in the nanometer scale, overcoming the computational limits of first-principles approaches. Our complete cluster dataset describes the evolution of topological properties with cluster size, capturing the complex variability of the carbon cluster family. As such, the dataset includes ordered and disordered structures, reproducing well-known clusters, like fullerenes, and predicting novel isomers.