3D Carbon Foam Research Articles

Three-dimensional carbon foam surrounded by carbon nanotubes and Co-Co3O4 nanoparticles for stable lithium-ion batteries

Three-dimensional (3D) carbon foams (CF) surrounded by carbon nanotubes (CNTs) and Co-Co3O4 nanoparticles (NPs) (CF@Co-Co3O4/CNT) nanocomposites were prepared by a two-step method for stable lithium-ion batteries (LIBs). The low-cost melamine foams pre-soaked in cobalt nitrate solution were firstly carbonized under nitrogen atmosphere to form 3D CF surrounded by a large number of CNTs and Co NPs (CF@Co/CNT). Subsequently, the CF@Co/CNT was transformed into CF@Co-Co3O4/CNT nanocomposites by calcination in air. Here, Co NPs, CNT and 3D CF all improved the electrical conductivity of CF@Co-Co3O4/CNT nanocomposites. In addition, a large number of uniformly-dispersed small Co3O4 NPs effectively increased Li+ storage capacity of nanocomposites. At the same time, the 3D macroporous carbon frameworks surrounded by CNT could also relieve the volume deformation of Co3O4 NPs to some extent. When it was employed as anode materials for LIBs, CF@Co-Co3O4/CNT nanocomposites exhibited the stable reversible capacities of about 500 mAh g−1 at 0.5 A g−1, larger than that of commercial graphite and some other Co-based materials. The two-step preparation method was simple and convenient for large-scale production.

3D honeycomb-like carbon foam synthesized with biomass buckwheat flour for high-performance supercapacitor electrodes.

A facile, one-step carbonization of buckwheat flour is innovated to synthesize honeycomb-like porous carbon, which exhibits specific capacitance (767 F g-1 at 1 A g-1) and stability with a retention of up to 92.6% after 10 000 cycles.

Enhanced photocatalytic activity of a mesoporous TiO2 aerogel decorated onto three-dimensional carbon foam

TiO2/carbon composites have been well studied as solar-light photocatalysts because they combine the advantages of TiO2 (good photocatalytic activity) and carbon (enhanced charge carrier separation). Mesoporous TiO2 aerogels are fragile by nature and the addition of free-standing three-dimensional (3D) porous carbon foam (CF) not only makes it easy for separation and collection after photocatalytic treatment but also acts as a scaffold for the long-term application of TiO2 aerogels in the photocatalysis. Hence, recent reports have shown that mesoporous TiO2 aerogel/CF composites synthesized by the carbonization of a polymer followed by using the sol-gel method are significant for use in photocatalysis applications. In addition, the 3D macroporous CF not only acts as a support for TiO2 aerogels but also improves the efficiency of light use and extends the photoresponse of TiO2 to the visible region. The TiO2 aerogel was homogeneously distributed onto the 3D CF because of the vacuum infiltration used during the synthesis of the composites. The simulated solar-light irradiated photocatalytic degradation of Rhodamine B organic pollutant was used to evaluate the TiO2 aerogel/CF composite catalysts, which was higher than with a pristine TiO2 aerogel. This facile synthesis approach for 3D foam type TiO2/carbon composites could be useful in the treatment of wastewater.

Low-Loading of Pt Nanoparticles on 3D Carbon Foam Support for Highly Active and Stable Hydrogen Production.

Minimizing Pt loading is essential for designing cost-effective water electrolyzers and fuel cell systems. Recently, three-dimensional macroporous open-pore electroactive supports have been widely regarded as promising architectures to lower loading amounts of Pt because of its large surface area, easy electrolyte access to Pt sites, and superior gas diffusion properties to accelerate diffusion of H2 bubbles from the Pt surface. However, studies to date have mainly focused on Pt loading on Ni-based 3D open pore supports which are prone to corrosion in highly acidic and alkaline conditions. Here, we investigate electrodeposition of Pt nanoparticles in low-loading amounts on commercially available, inexpensive, 3D carbon foam (CF) support and benchmark their activity and stability for electrolytic hydrogen production. We first elucidate the effect of deposition potential on the Pt nanoparticle size, density and subsequently its coverage on 3D CF. Analysis of the Pt deposit using scanning electron microscopy images reveal that for a given deposition charge density, the particle density increases (with cubic power) and particle size decreases (linearly) with deposition overpotential. A deposition potential of −0.4 V vs. standard calomel electrode (SCE) provided the highest Pt nanoparticle coverage on 3D CF surface. Different loading amounts of Pt (0.0075–0.1 mgPt/cm2) was then deposited on CF at −0.4 V vs. SCE and subsequently studied for its hydrogen evolution reaction (HER) activity in acidic 1M H2SO4 electrolyte. The Pt/CF catalyst with loading amounts as low as 0.06 mgPt/cm2 (10-fold lower than state-of-the-art commercial electrodes) demonstrated a mass activity of 2.6 ampere per milligram Pt at 200 mV overpotential, nearly 6-fold greater than the commercial Pt/C catalyst tested under similar conditions. The 3D architectured electrode also demonstrated excellent stability, showing <7% loss in activity after 60 h of constant current water electrolysis at 100 mA/cm2.

Processing, growth mechanism and thermodynamic calculations of carbon foam with a hollow tetrapodal morphology – Aerographite

Aerographite is a 3D interconnected carbon foam with a tetrapodal morphology. The synthesis of Aerographite is based on a two-step process: first the production of a zinc oxide (ZnO) template in a flame transport synthesis (FTS) followed by the replication into the carbon structure in a chemical vapour deposition process (CVD). This study presents a growth model of this 3D carbon foam via analyzing the newly formed carbon structure in an interrupted synthesis by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Raman spectroscopy. Moreover, the Gibbs free energy of the occurred replica CVD (rCVD) process, based on the reduction of ZnO and the formation of carbon layers, was calculated. During the CVD process the injected carbon deposits on the surfaces of the ZnO tetrapods, while simultaneously the replication into the carbon structure takes place, as a result of the reduction of ZnO into gaseous zinc and water vapour, which is due to the reaction of ZnO with the hydrogen (H2) from the injected source. This replication of the ZnO template into a carbon structure is based on an epitaxial controlled process combined with a catalytic graphitization, whereby the morphology of the template structure is replicated by the carbon. Furthermore, the influence of the growth process on the arrangement of carbon in layers and formation of defects was explained.

Synergistic effect of porous phosphosulfide and antimony nanospheres anchored on 3D carbon foam for enhanced long-life sodium storage performance

Phosphosulphide composites began to be used in energy storage field as an emerging category. However, the restricted variety of morphology structure, the large volume expansion and the poor electronic conductivity will lead to the inferior cycling stability. Herein combing with advantages of high electronic conductivity of metallic Sb and high theoretical capacity of phosphorus, non-metallic porous phosphosulfide nanospheres and ultrafine metallic Sb nanoparticles are synergistically anchored on 3D macroporous interconnected carbon foam to form Sb|P-S@C foam anode for high-performance sodium ion batteries (SIBs). The characteristics of porous feature of phosphosulfide nanospheres, high electrical conductivity and ultrafine size of Sb nanoparticles facilitate the alleviation of volume expansion and improvement of charge transfer and diffusion kinetics. 3D macroporous interconnected carbon foam as a framework offers enough active sites for the formation of Sb|P-S particles, not only effectually inhibiting the aggregation of Sb and phosphosulfide nanospheres due to the high surface energy and activity, but also effectively preventing anode material from pulverization and increasing the effective contact area between electrode and electrolyte, serving as 3D channel for electron/ion rapid transfer. Consequently, benefitting from the structural superiorities and synergistic effect, Sb|P-S@C foam anode delivers a specific capacity of 490 mAh g−1 with a remarkable capacity retention after 1000 cycles at 0.1 A g−1. The low-cost strategy for porous Sb|P-S@C foam anode sets up new paths to design long-cycling large-scale energy storage system.

Tailored crystalline width and wall thickness of an annealed 3D carbon foam composites and their mechanical properties

Carbon nanostructures in form of 3D carbon foams are mainly popular in materials community because of their ultralow densities, variable morphologies, and remarkable properties, etc. One of these foams is Aerographite, which exhibits a tetrapodal interconnected morphology. Similar to other synthetic carbon structures, the lattice defects are formed during the synthesis of Aerographite, which can be healed by a post-thermal treatment. Aerographite shows a property dependency on wall thickness (number of graphitic layers), which affects both, the electrical and mechanical properties. In this study, the wall thickness is tailored by varying of the total reaction time during the replication process. The influence of the thermal treatment of Aerographite on its mechanical performance in an Aerographite-epoxy nanocomposite, by determining the fracture toughness (K1C) in three-point bending tests (SEN-3PB), is investigated. An increase of the fracture toughness with increasing wall thickness is observed for untreated Aerographite. The graphitization of Aerographite leads to a reduction of the mechanical properties, by increasing the crystalline width. Consequently, the measured fracture toughness is dependent on the graphitization, the calculated crystalline width and the wall thickness of tubes in the hollow Aerographite tetrapodal network. Finally, based on these relations, a phenomenological mechanical failure model is developed and briefly discussed.

Hierarchical FeCo2 S4 Nanotube Arrays Deposited on 3D Carbon Foam as Binder-free Electrodes for High-performance Asymmetric Pseudocapacitors.

The ever-increasing global demand for green energy resources calls for more research attention on the development of cheap and efficient energy storage systems. Herein, we propose the rational design of a 3D carbon foam electrode deposited with perpendicularly oriented FeCo2 S4 nanotubes arrays (FeCo2 S4 /CMF) for high-performance asymmetric supercapacitors. In this work, the macroporous CMF served as conducting backbone not only to enhance the electrical conductivity of the composite, but also to promote the uniform growth of FeCo2 S4 nanotubes. Deposited hierarchical FeCo2 S4 nanotubes arrays with open hollow structures can afford numerous exposed electroactive sites for Faradaic redox reaction and provide short interior channels for fast electrolyte transmission. Due to these unique features, obtained 3D hierarchical FeCo2 S4 /CMF composite foam exhibits a high specific capacitance of 2430 F g-1 (specific capacity of 337.5 mAh g-1 ) at 1 A g-1 , and excellent capacitance retention of 91 % after 5000 cycles at a high current density of 9 A g-1 , which is superior to most of those previously reported binary metal sulfide-based electrodes. Moreover, asymmetric supercapacitor device assembled using the FeCo2 S4 /CMF as positive electrode also delivers a high energy density of 78.7 W h kg-1 at a power density of 800.3 W kg-1 . Therefore, this work provides a new strategy for the low-cost synthesis of 3D foam electrodes towards high-performance supercapacitor devices.

High-performance supercapacitor fabricated from 3D free-standing hierarchical carbon foam-supported two dimensional porous thin carbon nanosheets

In the present work, carbon composite of two dimensional porous thin carbon nanosheets hybrized with 3D freestanding hierarchical carbon foam (2D-CNs/3D-CF) was successfully fabricated for the first time via a facile impregnation and high temperature annealing strategy. The structure characterizations confirmed that 2D carbon nanosheets with a thickness of ∼8 nm and a plentiful pore channels were successfully assembled on the surface of 3D carbon foam skeleton. With such ultralight, flexible and porous 2D/3D hybrid carbon nanocomposite as active electrode material, a large specific surface area can be available and rapid electron transfer and ionic transport are facilitated. The electrochemical measurements demonstrated that the 2D-CNs/3D-CF-based supercapacitor presents an excellent specific capacitance of 364 F g−1 at 1 A g−1 and even a high specific capacitance of 321.86 F g−1 can be achieved at 10 A g−1 in 6.0 M KOH aqueous solution. Taking a comparison with the previously reported capacitor materials, the as-prepared hybrid carbon exhibited higher capacitance properties. Furthermore, the 2D/3D carbon-based supercapacitor exhibited an energy density of 47.30 Wh kg−1 at a power density of 0.84 kW kg−1 and the energy density can still retain 23.90 Wh kg−1 even when power density runs up to 80.11 kW kg−1 at a relatively high current density of 200 A g−1, demonstrating the superior capacitor performance and extremely high power density and energy density. Such novel carbon nanostructure with 3D freestanding hierarchical carbon foam hybrized with 2D porous carbon nanosheets may have promising application in energy storage devices.

Manufacturing of a hierarchical carbon foam with tailored catalytically Me/MexOy particles

Carbon foams are characterised by their high specific surface areas (SSAs) in combination with ultra-low densities. Due to these unique properties, carbon foams are particularly suitable for applications such as catalysts, where high surface area is essential. Metals or metal oxides are added to the carbon structure to increase the catalytically effectiveness. In this study, we present a new and efficient manufacturing method, with the potential for a large-scale production resulting in a 3D hierarchical carbon foam with incorporated catalytically metal or metal oxides. The manufacturing starts with the preparation of a ceramic zinc oxide (ZnO) precursor powder containing catalytically active materials (Me/MexOy), uniaxial pressing and sintering yielding to templates. The replication of the template morphology into a hollow carbon structure in the chemical vapour deposition (CVD) process, in which the catalytic materials remain in the carbon foam. Furthermore, the morphology of these structures and the grain size distribution are investigated using scanning electron (SEM) and transmission electron microscopy (TEM). The final amount of catalytically particles is analysed by thermal gravimetric analysis (TGA). Finally, the SSA of the synthesised carbon-based catalysts is measured by Brunauer-Emmett-Teller (BET) method.

Steamed cake-derived 3D carbon foam with surface anchored carbon nanoparticles as freestanding anodes for high-performance microbial fuel cells

Anode design is highly significant for microbial fuel cells, since it simultaneously serves as the scaffold for electroactive microorganisms and as a medium for electron migration. In this study, a stiff 3D carbon foam with surface anchored nitrogen-containing carbon nanoparticles was facilely constructed via in-situ polyaniline coating of carbonized steamed cake prior to the carbonization process. The resultant product was determined to be an excellent freestanding anode that enabled the microbial fuel cell to deliver a maximum power density of up to 1307 mW/m2, which significantly outperformed its non-coated counterpart, the widely used commercial carbon felt. Further investigations revealed that the overall performance enhancement was associated with the open porosity, enlarged electroactive surface, increased biocompatibility, and decreased electric resistance of the anode scaffold. This promising anode material would offer a green and economical option for fabricating high-performance microbial fuel cell-based devices towards various ends.

The negative Poisson's ratio in graphene-based carbon foams.

Using molecular dynamics simulations, we find an in-plane negative Poisson's ratio intrinsically existing in the graphene-based three-dimensional (3D) carbon foams (CFs) when they are compressed uniaxially. Our study shows that the negative Poisson's ratio in the present CFs is attributed to their unique molecular structures and triggered by the buckling of the CF structures. This mechanism makes the negative Poisson's ratio of CFs strongly depend on their cell length, which offers us an efficient means to tune the negative Poisson's ratio in nanomaterials. Moreover, as the buckling modes of CFs are topographically different when they are compressed in different directions, their negative Poisson's ratio is found to be strongly anisotropic, which is in contrast to the isotropic positive Poisson's ratio observed in CFs prior to buckling. The discovery of the intrinsic negative Poisson's ratio in 3D CFs will significantly expand the family of auxetic nanomaterials. Meanwhile, the mechanism of nano-auxetics proposed here may open up a door to manufacture new auxetic materials on the nanoscale.

Long-life electrochemical supercapacitor based on a novel hierarchically carbon foam templated carbon nanotube electrode

Abstract In this work, a long-life and high-performance electrode material is successfully fabricated by the incorporation of carbon nanotube (CNT) with different length using chemical vapor deposition (CVD) on a hierarchically three dimensional (3D) carbon foam (CF), which is obtained from the mesophase pitch. The morphology, composition, and electrochemical performance of the as-prepared composites are characterized using the scanning electron microscope (SEM), Raman spectroscopy, X-ray diffraction (XRD) patterns, cyclic voltammetry, and galvanostatic charge/discharge cycling techniques. Characterizations suggest that this resultant CF/CNT-50 electrode material has a good cycling stability with capacitance retention of 96.5% even after 10000 cycles. Moreover, it shows a high mass capacitance of 227.5 F/g based on the resultant electrode materials, higher energy density of 28 Wh kg−1 and power density of 3700 W kg−1 at a current density 2 A g−1 and also excellent charge/discharge rate. These measured charge storage properties make the proposed hybrid materials excellent electrode material candidates for high performance supercapacitors.

Fundamentals of the temperature-dependent electrical conductivity of a 3D carbon foam—Aerographite

Aerographite is a 3D interconnected carbon foam with a hollow tetrapodal morphology. The properties of Aerographite, especially the electrical conductivity, are strongly dependent on the wall thickness, the degree of graphitization and the ambient temperature. The tailored-carbon-structures like wall thickness (number of layer) and state of graphitization determine the electrical properties of the carbon foam. The wall thickness of Aerographite can be controlled by a stepwise reduction of solid arms of sacrificial template with respect to synthesis time, in which wall thicknesses between 3 and 22 nm can be easily achieved. The decreasing of the wall thickness leads to a reduced electrical conductivity of untreated Aerographite. Contrary, the conductivity of annealed Aerographite increased with reducing of the wall thicknesses. The morphology of Aerographite has been analyzed via scanning electron (SEM), transmission electron (TEM) microscopy and Raman spectroscopy. Furthermore, the dependency of the electrical conductivity on the temperature is measured and based on this the band gap energy is calculated. As a result, Aerographite shows a metallic conductive behaviour which can be changed semiconducting nature by further high temperature treatment.

A metal-free and non-precious multifunctional 3D carbon foam for high-energy density supercapacitors and enhanced power generation in microbial fuel cells

This paper reports the synthesis of N-doped carbon foams (NCFs) using simple, environment-friendly, and self-developed freezing method. A robust structure of NCFs along with high surface area, hierarchical pore structure, and nitrogen/oxygen functionalities allows their application as free-standing electrode. Microbial fuel cell equipped with differently prepared NCFs as free-standing anode and metal-free cathode generates significantly higher power density, 35.74Wm−3 than conventional electrodes. Furthermore, NCF with an optimized resorcinol-formaldehyde content shows significantly high-charge storage capacity, 799Fg−1, at 0.25Ag−1 and also delivers a high energy density, 111Whkg−1, equivalent to that of a Li-ion battery.

3D nitrogen-doped carbon foam supported Ge@C composite as anode for high performance lithium-ion battery

In this work, we successfully designed and synthesized Ge nanoparticles encapsulated in a carbon matrix and supported by three-dimensional interconnected porous N-doped carbon foam (3D Ge/C-NCF) nanoarchitecture. When applied as an anode material for lithium ion batteries, the obtained composite electrode exhibits high capacity of 878.1mAhg−1 at a current density of 0.5Ag−1 after 150 cycles. Additionally, it also achieves excellent rate capability and cycling stability. The significant improved electrochemical performance of Ge/C-NCF can be attributed to the synergetic effects of the carbon matrix and the N-doped carbon framework: including a highly conductive carbon network and a structure with large porous for mitigates volume changes of Ge nanoparticles. This study of the composite electrode may provide an interesting method to creating efficient and practical electrodes for those that suffer from huge volume expansion for energy storage applications.

β-FeOOH Nanorods/Carbon Foam-Based Hierarchically Porous Monolith for Highly Effective Arsenic Removal.

Arsenic pollution in waters has become a worldwide issue, constituting a severe hazard to whole ecosystems and public health worldwide. Accordingly, it is highly desirable to design high-performance adsorbents for arsenic decontamination. Herein, a feasible strategy is developed for in situ growth of β-FeOOH nanorods (NRs) on a three-dimensional (3D) carbon foam (CF) skeleton via a simple calcination process and subsequent hydrothermal treatment. The as-fabricated 3D β-FeOOH NRs/CF monolith can be innovatively utilized for arsenic remediation from contaminated aqueous systems, accompanied by remarkably high uptake capacity of 103.4 mg/g for arsenite and 172.9 mg/g for arsenate. The superior arsenic uptake performance can be ascribed to abundant active sites and hydroxyl functional groups available as well as efficient mass transfer associated with interconnected hierarchical porous networks. In addition, the as-obtained material exhibits exceptional sorption selectivity toward arsenic over other coexisting anions at high levels, which can be ascribed to strong affinity between active sites and arsenic. More importantly, the free-standing 3D porous monolith not only makes it easy for separation and collection after treatment but also efficiently prevents the undesirable potential release of nanoparticles into aquatic environments while maintaining the outstanding properties of nanometer-scale building blocks. Furthermore, the monolith absorbent is able to be effectively regenerated and reused for five cycles with negligible decrease in arsenic removal. In view of extremely high adsorption capacities, preferable sorption selectivity, satisfactory recyclability, as well as facile separation nature, the obtained 3D β-FeOOH NRs/CF monolith holds a great potential for arsenic decontamination in practical applications.

Assembling carbon fiber–graphene–carbon fiber hetero-structures into 1D–2D–1D junction fillers and patterned structures for improved microwave absorption

Since carbon-based structures of various dimensions, including one-dimensional (1D) carbon nanotubes, two-dimensional (2D) graphene and three-dimensional (3D) carbon foams, have attracted significant attention as microwave absorption fillers, we present an exceptional hetero-junction filler with a 1D–2D–1D feature, achieved by manipulating 2D graphene into 1D carbon fibers in the fiber-extruding process under the electric field. The as-fabricated 1D–2D–1D structural fillers exhibited much-improved dielectric properties and promoted microwave absorption performance in their composites, which is linked to the establishment of enhanced polarization capability, the generation of increased electric loss pathway and the creation of more favorable electromagnetic energy consumption conditions. The results suggest that employing 2D graphene in the 1D–2D–1D nanostructures played the critical role in tuning the electromagnetic response ability, because of its intrinsic electric advantages and dimensional features. To broaden the effective absorption bandwidth, periodic pattern-absorbing structures were designed, which showed combined absorption advantages for various thicknesses. Our strategy for fabricating 1D–2D–1D structural fillers illuminates a universal approach for manipulating dimensions and structures in the nanotechnology.

In situ growth of α-Fe2O3 nanorod arrays on 3D carbon foam as an efficient binder-free electrode for highly sensitive and specific determination of nitrite

3D α-Fe2O3 nanorod arrays (NAs)/carbon foam (CF) architectures have been successfully fabricated as binder-free electrodes for the determination of nitrite, exhibiting high sensitivity and excellent specific recognition as well as feasibility in real water samples.

PolyHIPE Derived Freestanding 3D Carbon Foam for Cobalt Hydroxide Nanorods Based High Performance Supercapacitor.

The current paper describes enhanced electrochemical capacitive performance of chemically grown Cobalt hydroxide (Co(OH)2) nanorods (NRs) decorated porous three dimensional graphitic carbon foam (Co(OH)2/3D GCF) as a supercapacitor electrode. Freestanding 3D porous GCF is prepared by carbonizing, high internal phase emulsion (HIPE) polymerized styrene and divinylbenzene. The PolyHIPE was sulfonated and carbonized at temperature up to 850 °C to obtain graphitic 3D carbon foam with high surface area (389 m2 g−1) having open voids (14 μm) interconnected by windows (4 μm) in monolithic form. Moreover, entangled Co(OH)2 NRs are anchored on 3D GCF electrodes by using a facile chemical bath deposition (CBD) method. The wide porous structure with high specific surface area (520 m2 g−1) access offered by the interconnected 3D GCF along with Co(OH)2 NRs morphology, displays ultrahigh specific capacitance, specific energy and power. The Co(OH)2/3D GCF electrode exhibits maximum specific capacitance about ~1235 F g−1 at ~1 A g−1 charge-discharge current density, in 1 M aqueous KOH solution. These results endorse potential applicability of Co(OH)2/3D GCF electrode in supercapacitors and signifies that, the porous GCF is a proficient 3D freestanding framework for loading pseudocapacitive nanostructured materials.