Hollow Carbon Particles Research Articles

Carbon Nanotubes an Excellent Targeted Drug Delivery System

Carbon nanotubes, or CNTs, are carbon allotropes with a nanostructure that can have a length-to-breadth proportion more prominent than 1,000,000. These round and hollow carbon particles have exceptional properties that make them possibly helpful in an assortment of nanotechnology applications. CNTs might be joined with a scope of natural components, including proteins, drugs, and nucleic acids, to give bio-functionalities. CNTs come in two assortments: multi-walled (MWNTs) and single-walled (SWNTs). Among its captivating properties are its high viewpoint proportion, strength, lightweight weight, high warm conductivity, and electrical attributes that reach from metallic to semiconducting. Carbon nanotubes might be made by various cycles, including warm blend, substance fume statement, laser removal, circular segment release dissipation, plasma-based union, and synthetic fume affidavit increased by plasma. Carbon nanotubes (CNTs) track down use in drug conveyance, blood malignant growth, bosom disease, cerebrum malignant growth, liver malignant growth, cervical malignant growth, quality treatment, resistant therapy, biomedical imaging, biosensors, and tissue designing. The noncovalent functionalization of specific MNTs with folic corrosive (FA) worked on the vehicle of medication to malignant growth cells in the lymph hubs. By utilizing a remotely introduced magnet to guide the medication lattice to the provincial designated lymph hubs, the MNTs can ceaselessly deliver chemotherapeutic medications for a few days while remaining in the depleting designated lymph hubs. Growth cells communicating folate receptors (FRs) in the lymph hubs can be explicitly obliterated since FRs are overexpressed in different human malignancies.

Synergistically enhanced electromagnetic absorption in barium ferrite/hollow carbon spheres/epoxy composites

The ongoing technological advancements have emphasized the importance of absorbent coatings, which are essential for effectively absorbing electromagnetic waves across various industries, including electronics, healthcare, and security systems. In this research, barium ferrite particles and hollow spherical carbon particles have been synthesized to investigate the synergistic effect of different compounds in absorbing electromagnetic waves in the epoxy coating. The barium ferrite particles were synthesized in two distinctive rod and spherical morphologies at 600 and 900 °C, employing the sol-gel technique. Also, hollow spherical carbon particles were synthesized. Synthesized particles were analyzed structurally and chemically with an X-ray Powder Diffraction, Fourier infrared spectrometer, vibrating‐sample magnetometer, field emission Scanning Electron, and Raman spectroscopy.The absorption characteristics of a coating that contains rod and spherical morphologies of barium ferrite and hollow spherical carbon particles can be adjusted by controlling the amounts of synthetic compounds in the 8–12 GHz range. The results indicate that combining rod-shaped barium ferrite particles (900 °C) and hollow spherical carbon particles in a thin epoxy coating improves impedance matching and wave attenuation. Notably, when the epoxy coating is 1.5–2 mm thick and contains 20 % rod-shaped barium ferrite particles (900 °C) and 1 % hollow spherical carbon particles, reflection loss values of < -20 dB are observed at frequencies of 10–12 GHz.

Coupling effects of dielectric loss in N-doped carbon double-shelled hollow particles for high-performance microwave absorption

Microwave absorbing materials with lightweight and high-performance are of great significance for electronic technique, ecological environment and defense applications. The hollow structure of carbon microspheres is beneficial to achievement of high-performance microwave absorption due to high interfacial polarization. However, the key characteristic is still unclear to control interfacial polarization. Herein, double-shelled N-doped carbon hollow particles derived from polypyrrole by self-sacrifice template were synthesized. The polymerization process was controlled by the interface between solid and pyrrole acid liquid in Fe3O4 disperse system, subsequently, micro-nano structure of carbon was tuned. The N-doped carbon double-shelled hollow particles (DSHS) show a strong dielectric loss due to coupling effect of resistance loss and interfacial polarization owing to the double-shelled hollow structure. Thus, DSHS shows a high-performance microwave absorption with minimum reflection loss (RLmin) of −75.10 dB at a thickness of 2.48 mm and effective absorption bandwidth (RL ≤ -10 dB) of 6.08 GHz and 4.05 GHz covering the whole Ku band and almost the whole X with a thickness of 2.21 mm and 3.00 mm, respectively. This work provides a simple approach for synthesizing N-doped carbon particles with distinct micro-nano hierarchical structure, double-shelled hollow microspheres assembled by nanoparticles have potential application as a high-performance MAM.

Hierarchical Hollow Carbon Particles with Encapsulation of Carbon Nanotubes for High Performance Supercapacitors.

A novel and sustainable carbon-based material, referred to as hollow porous carbon particles encapsulating multi-wall carbon nanotubes (MWCNTs) (CNTs@HPC), is synthesized for use in supercapacitors. The synthesis process involves utilizing LTA zeolite as a rigid template and dopamine hydrochloride (DA) as the carbon source, along with catalytic decomposition of methane (CDM) to simultaneously produce MWCNTs and COx -free H2 . The findings reveal a distinctive hierarchical porous structure, comprising macropores, mesopores, and micropores, resulting in a total specific surface area (SSA) of 913 m2 g-1 . The optimal CNTs@HPC demonstrates a specific capacitance of 306 Fg-1 at a current density of 1 Ag-1 . Moreover, this material demonstrates an electric double-layer capacitor (EDLC) that surpasses conventional capabilities by exhibiting additional pseudocapacitance characteristics. These properties are attributed to redox reactions facilitated by the increased charge density resulting from the attraction of ions to nickel oxides, which is made possible by the material's enhanced hydrophilicity. The heightened hydrophilicity can be attributed to the presence of residual silicon-aluminum elements in CNTs@HPC, a direct outcome of the unique synthesis approach involving nickel phyllosilicate in CDM. As a result of this synthesis strategy, the material possesses excellent conductivity, enabling rapid transportation of electrolyte ions and delivering outstanding capacitive performance.

Effect of oxidation temperature on oxidation reactivity and nanostructure of particulate matter from a China VI GDI vehicle

Modern Gasoline Direct Injection (GDI) vehicles offered higher power output, improved fuel economy and reduced CO2 emissions compared with port fuel injection (PFI) vehicles. However, the particle number emission of GDI is larger than that of PFI and also higher than diesel vehicles equipped with diesel particle filter (DPF). This research sampled particle matter (PM) emitted from a China VI vehicle over the Worldwide harmonized Light vehicles Test Cycle (WLTC). The results of particle size distribution showed that ultra-fine particles in diameter below 23 nm take up majority of particle emissions. While with the oxidation temperature rising, the peak diameter of emitted particles migrated to larger section. The effect of oxidation temperature including interlayer spacing, fractal dimension, fringe length and tortuosity have been analyzed by TEM. The value of nano structural parameters increases slightly with the temperature increasing. Besides, the impact of volatile components was considered into the micromorphology and microstructure parameters of primary particles. After eliminating volatile materials, there is no presence of hollow carbon particles and all the three parameters including interlayer spacing, fringe length and fringe tortuosity showed an overall decrease. Better understanding nano structural parameters of PM under different oxidation temperatures can provide information to explain the potential impacts of particle emissions on human health and environment and the regeneration process of gasoline particle filter (GPF).

Sustainable porous hollow carbon spheres with high specific surface area derived from Kraft lignin

Hollow carbon spheres (HCSs) have attracted tremendous interest in recent years due to their intriguing structure-induced physicochemical properties and significant potential for numerous applications. However, the preparation of HCSs with precise structural control using a simple and scalable strategy remains challenging. In this work, hollow carbon particles having a well-defined spherical morphology were successfully produced using a green, economical, and facile spray drying method together with a carbonization process. Kraft lignin was employed as the carbon precursor in place of lignosulfonate with potassium hydroxide (KOH) as an activation agent. The high specific surface area (1536.5–2424.8 m2 g−1) with micro-mesoporous structure of HCSs can be easily tuned by controlling the mass ratio of KOH to carbon precursor. The KOH-to-lignin mass ratios were utilized below 1.5, lower than those in previous studies typically used higher than 3, which was in accordance with green chemistry principles. In addition, these HCSs have applications as electrode materials in supercapacitors for energy storage devices. With the great achievements and continuous efforts in this important field, these results suggest that our approach will open a new path for the development of advanced carbon materials and high value-added utilization of Kraft lignin as a promising material for potential applications.

Metal-Organic Framework-Derived Co3 V2 O8 @CuV2 O6 Hybrid Architecture as a Multifunctional Binder-Free Electrode for Li-Ion Batteries and Hybrid Supercapacitors.

Metal-organic frameworks (MOFs) are promising materials in diverse fields because of their constructive traits of varied structural topologies, high porosity, and high surface area. MOFs are also an ideal precursor/template to derive porous and functional morphologies. Herein, Co3 V2 O8 nanohexagonal prisms are grafted on CuV2 O6 nanorod arrays (CuV-CoV)-grown copper foam (CF) using solution-processing methods, followed by thermal treatment. Direct preparation of active material on CF can potentially eliminate electrochemically inactive and non-conductive binders, leading to improved charge-transfer rate. Furthermore, solution-processing methods are simple and cost-effective. Owing to versatile valence states and good redox activity, the vanadium-incorporated mixed metal oxides (CuV-CoV) exhibited superior electrochemical performance in lithium (Li)-ion battery and supercapacitor (SC) studies. Furthermore, hollow carbon particles (HCPs) derived from MOF particles (MOF-HCPs) are used as the anode material in SCs. A hybrid SC (HSC) fabricated with CuV-CoV and MOF-HCP materials exhibited noteworthy electrochemical properties. Moreover, a solid-state HSC (SSHSC) is constructed and its real-time feasibility is investigated by harvesting the dynamic energy of a bicycle with the help of a direct current generator. The charged SSHSCs potentially powered various electronic components.

Synthesis of Porous Carbon Hollow Particles from Polymer Hollow Particles

Synthesis of Porous Carbon Hollow Particles from Polymer Hollow Particles

S/N Co-Doped Hollow Carbon Particles for Oxygen Reduction Electrocatalysts Prepared by Spontaneous Polymerization at Oil-Water Interfaces.

We herein report that sulfur and nitrogen co-doped hollow spherical carbon particles can be applied to oxygen reduction reaction (ORR) electrocatalysts prepared by calcination of polydopamine (PDA) hollow particles. The hollow structure of PDA was formed by auto-oxidative interfacial polymerization of dopamine at the oil and water interface of emulsion microdroplets. The PDA was used as the nitrogen source as well as a platform for sulfur-doping. The obtained sulfur and nitrogen co-doped hollow particles showed a higher catalytic activity than that of nonsulfur-doped particles and nonhollow particles. The high ORR activity of the calcined S-doped PDA hollow particles could be attributed to the combination of nitrogen and sulfur active sites and the large surface areas owing to a hollow spherical structure.

Double-Shelled C@MoS2 Structures Preloaded with Sulfur: An Additive Reservoir for Stable Lithium Metal Anodes.

The growth of Li dendrites hinders the practical application of lithium metal anodes (LMAs). In this work, a hollow nanostructure, based on hierarchical MoS2 coated hollow carbon particles preloaded with sulfur (C@MoS2 /S), was designed to modify the LMA. The C@MoS2 hollow nanostructures serve as a good scaffold for repeated Li plating/stripping. More importantly, the encapsulated sulfur could gradually release lithium polysulfides during the Li plating/stripping, acting as an effective additive to promote the formation of a mosaic solid electrolyte interphase layer embedded with crystalline hybrid lithium-based components. These two factors together effectively suppress the growth of Li dendrites. The as-modified LMA shows a high Coulombic efficiency of 98 % over 500 cycles at the current density of 1 mA cm-2 . When matched with a LiFePO4 cathode, the assembled full cell displays a highly improved cycle life of 300 cycles, implying the feasibility of the proposed LMA.

Hydrothermal controllable synthesis of hollow carbon particles: Reaction-growth mechanism

In this work, the reaction and growth mechanism of carbon particles synthesized via hydrothermal method have been studied. The reaction mechanism of d-glucose – d-ribose – Furanic group – Arene group (DDFA) and growth mechanism of P123 – Sphere micelle – Hollow carbon sphere – Hollow vase-like carbon particle (PSHH) were proposed. It was found that the morphology, average particle size and particle size distribution of carbon particles can be varied by regulating operating conditions. In addition, the prepared hollow vase-like carbon particle (HVCP) was adopted as an adsorbent and for preparing catalyst. The results showed that the HVCP adsorption capacity is 4.5 times higher than commercial activated carbon (CAC) for phenol adsorption, and could great enhance the photocatalytic degradation of phenol. This work may provide guidance for controllable synthesis of carbonaceous materials and research method for the related reaction and growth mechanism.

Hierarchically porous carbon nanofibers embedded with cobalt nanoparticles for efficient H2O2 detection on multiple sensor platforms

Hydrogen peroxide (H2O2) detection is essential in many industrial and biological processes. Current applications of H2O2 electrochemical sensors are often limited by the high cost of precious metal electrocatalysts and sophisticated instrumentation requirements. Here, we demonstrate a highly active non-precious metal cobalt/carbon nanocomposite electrocatalyst for efficient H2O2 sensing on multiple sensor platforms, including conventional glassy carbon electrodes (GCEs), free-standing film electrodes, and screen-printed electrodes (SPEs). This nanocomposite was synthesized by carbonation of electrospun polyacrylonitrile nanofibers containing zeolitic imidazole framework (i.e., ZIF-67) particles. The resulting hierarchically porous nitrogen-doped carbon nanofiber film contains hollow mesoporous carbon particles and exposed cobalt nanoparticles, which has sufficient mechanical strength as a self-standing film and is also electrically highly conductive. Consequently, when tested using GCEs, it exhibits an ultrahigh sensitivity of 300 μA/cm2 mM and a detection limit of 10 μM below the permissible H2O2 residual limit in food packaging permittable by the US FDA. When utilized as free-standing film electrodes, its linear detection range extends an order higher to 50 mM. It is also highly specific toward H2O2 sensing without responses to multiple interfering analytes. Further, it enables mobile H2O2 detection on SPEs when integrated with a portable potentiostat and mobile phone. This new nanocomposite electrocatalyst can open various new opportunities for practical H2O2 sensing applications.

Synthesis of porous carbon hollow particles maintaining their structure using hyper-cross-linked Poly(St-DVB) hollow particles

Porous carbon hollow particles (PCHPs) have many useful features such as a high specific surface area, large pore volume, and the presence of nanovoids, giving them potential for use in catalyst carriers, supercapacitors, and Li-ion batteries. However, conventional synthesis methods have many problems. In this study, we developed a new method to produce hollow polymer particles that retain their structure after carbonization, without using any templates which need to be removed later. These poly(styrene-divinylbenzene) (Poly(St-DVB)) hollow particles are hyper-cross-linked by Friedel-Crafts alkylation, which prevents collapse during carbonization. The synthesized PCHPs have a large specific surface area, and abundant micropores and macropores derived from their hollow structure. The shell of the PCHPs was found to be composed of amorphous carbon partially crystallized as graphite.

Hybrids of Bowl-like and Crumpled Hollow Carbon Particles Synthesized through Encapsulation Templating.

The one-pot synthesis of hybrid hollow nanoparticles of symmetric and asymmetric shapes is a challenging task and has rarely been reported. This work proposes a method for a high-yield synthesis of hybrid hollow carbon particles. In the first step, hexadecane/styrene (HD/St) is encapsulated in a silica shell. Then, by the polymerization of St, a silica/polystyrene double shell is formed. Finally, hollow carbon particles with bowl-like and crumpled shapes are obtained by carbonization. The results show that the ratio of diameter to thickness (D/H) for obtaining crumpled particles is ∼4-12, whereas this ratio is ∼7-18 for bowl-like particles. We study the effects of HD and St concentrations on the D/H ratio and the composition of hybrid particles. In contrast to suspensions of hollow carbon spheres, the suspensions of hybrid nanoparticles show shear-thinning behavior over the examined range of shear rates, which is attributed to their enhanced packing. The shape effect of hybrid particles also increases their adsorption on human mesenchymal stem cells (hMSCs) compared to the hollow carbon spheres.

Characterization of nanoscale detonation carbon produced in a pulse gas-detonation device

Nanoscale Detonation Carbon (NDC) was produced in a Pulse Gas-Detonation Device (PGDD) by detonation of C2H2 + kO2 mixtures, with variation of k from 0.11 to 0.82. The obtained NDC was characterized using Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), X-Ray Diffractometry (XRD), Raman Spectroscopy (RS), and X-Ray Photoelectron Spectroscopy (XPS). It was shown that the morphology and structure of the carbon particles change significantly with increase of the oxygen to carbon molar ratio. As oxygen content increases (k increases from 0.11 to 0.51), hollow rounded carbon particles grow in size reaching 200 nm in diameter. At oxygen content above some critical value (k is >0.60), the particles acquire a shape of graphene-like flakes with a thickness of up to 20 nm. The degree of graphitization of NDC increases rapidly with the growth of oxygen to carbon molar ratio up to k = 0.51. With a further increase in k, the growth rate of the degree of graphitization slows down. It was also found that graphitization of NDC is affected by the length of the barrel of a PGDD, the addition of argon to the acetylene-oxygen mixture, and the nature of the purge gas (nitrogen or argon). The XPS analysis revealed the presence of adsorbed water, as well as hydroxyl and carbonate groups on the surface of NDC particles. With an increase in k from 0.11 to 0.68, the specific surface area of NDC SBET decreases from 230 to 107 m2/g.

An in Situ Template for the Synthesis of Tunable Hollow Carbon Particles for High-Performance Lithium-Sulfur Batteries.

Nanostructured materials with hollow interior voids are gaining great attention due to their fantastic geometries and unique physicochemical properties competent for many applications. However, the development of a fast approach to prepare the hollow structured particles remains challenging. Herein, a new and efficient in situ hard-template method was developed to synthesize hollow carbon nano- and microparticles using the as-prepared SiO2 particles as a hard template directly, without any separation, drying, or redispersion. In this way, the hollow carbon particles with tunable diameters and shell thickness can be synthesized readily, which is simpler and more efficient than the traditional ones. In addition, the universality of this strategy allows us to study the different behaviors of hollow carbon particles in lithium–sulfur batteries when the architectures of hollow particles (i.e., diameter, shell thickness, etc.) were changed. We believe that this in situ method is applicable for synthesizing other core–shell or hollow structured materials (e.g., metal oxide), and also, the high performance of hollow carbon particles in lithium–sulfur batteries and beyond can be further explored.

Products on electrodes in an argon-methane magnetically rotating arc at atmospheric pressure

The arc discharge method in a hydrocarbon atmosphere has a promising application in the nanocarbon synthesis field due to its high yield. In this paper, products on electrodes in an argon-methane magnetically rotating arc at atmospheric pressure are investigated. Different nanocarbons are obtained on the cathode and anode surfaces, respectively. Material analysis indicates that the products on the cathode are mainly carbon tubes. Some carbon tubes are well-aligned in one direction, and the others have a coil-like structure. The products on the anode are a mixture of graphene nano-flakes and aggregate hollow carbon particles. The hollow carbon particles exhibit a chain-like structure with internal space to be connected. To the authors’ knowledge, this is possibly the first time that aggregate hollow carbon particles with a chain-like structure have been observed in the absence of any catalyst. Based on the configuration of arc plasma, the formation mechanism of electrode products is briefly proposed.

A bio-inspired N-doped porous carbon electrocatalyst with hierarchical superstructure for efficient oxygen reduction reaction

The bio-inspired hierarchical “grape cluster” superstructure provides an effective integration of one-dimensional carbon nanofibers (CNF) with isolated carbonaceous nanoparticles into three-dimensional (3D) conductive frameworks for efficient electron and mass transfer. Herein, a 3D N-doped porous carbon electrocatalyst consisting of carbon nanofibers with grape-like N-doped hollow carbon particles (CNF@NC) has been prepared through a simple electrospinning strategy combined with in-situ growth and carbonization processes. Such a bio-inspired hierarchically organized conductive network largely facilitates both the mass diffusion and electron transfer during the oxygen reduction reactions (ORR). Therefore, the metal-free CNF@NC catalyst demonstrates superior catalytic activity with an absolute four-electron transfer mechanism, strong methanol tolerance and good long-term stability towards ORR in alkaline media.

A facile soft template method to synthesize hollow carbon and MnO x composite particles for effective methylene blue degradation.

Hollow carbon and MnOx composite particles (HC-Mn) were fabricated by using polyacrylic acid (PAA) and Mn ion co-assembled colloids as the soft template and resorcinol formaldehyde resin (RF) as the carbon source. The formation process was well studied and a plausible formation mechanism was proposed. The Mn ions played two key roles in the synthesis: first, they promoted the aggregation of the PAA molecules, thus forming the PAA–Mn colloids in solution with high water content, which were suitable for the subsequent RF coating. Secondly, considerable Mn ions were retained after template removal, which were transformed into MnOx particles simultaneously during carbonization. This approach was facile and effective and the as-prepared HC-Mn showed superior catalytic activity toward methylene blue (MB) degradation.

Formation of Single-Holed Cobalt/N-Doped Carbon Hollow Particles with Enhanced Electrocatalytic Activity toward Oxygen Reduction Reaction in Alkaline Media.

Design and construction of metal‐organic framework (MOF) composite precursors have recently been considered as a promising strategy for the preparation of different structured metal/carbon‐based functional materials. Here, an MOF composite‐assisted strategy to synthesize single‐holed cobalt/N‐doped carbon hollow particles is reported. The yolk–shell polystyrene@zeolitic imidazolate framework‐67 (PS@ZIF‐67) composite precursors are first synthesized, followed by a controlled pyrolysis to obtain cobalt/N‐doped carbon hollow particles with a large single hole on each shell. Moreover, the MOF‐coating approach reported in this work can be extended to prepare various core‐shell ZIF‐67 composites with different structures and compositions. Benefiting from the structural and compositional advantages, the as‐derived single‐holed cobalt/N‐doped carbon hollow particles manifest superior electrocatalytic oxygen reduction performance with high activity and excellent durability.