Carbonaceous Composites Research Articles

Implications of nanomaterials reinforcement along with sub-zero temperature cooling on microstructure and mechanical properties of friction stir processed Al7075 alloy

Al 7075 surface composites (SCs) successfully fabricated with additive three different nano-scale particles multi-walled carbon nanotubes (MWCNTs), graphene (GNP), and titanium dioxide (TiO2) by friction stir processing (FSP). The consecutive two-pass FSP was executed under a controlled cooling environment at −20 °C with methanol pumped beneath the workpiece in a specially designed fixture. All of the SCs exhibited homogenous dispersion of filler nanoparticles in their microstructures. The grain size of SCs was remarkably reduced from that of the substrate. The enhancement in hardness and strength was ascribed fundamentally to the grain refinement and Zener (pinning) effect expedited by coolant circulation. The effect of second phase matrix on grain evolution and precipitate-intermetallics formed after FSP was characterized by scanning electron microscope (SEM) and XRD pattern. It has been recorded that there is around 95–110% increase in hardness values in SCs. The wear rate is also dropped in SCs owing to enhanced hardness and the formation of lubricating coating in the case of carbonaceous composites.

Ant‐Nest‐Inspired Biomimetic Composite for Self‐Cleaning, Heat‐Insulating, and Highly Efficient Electromagnetic Wave Absorption

AbstractThe pursuit of eco‐friendly electromagnetic wave absorption (EMWA) materials with multifunctional capabilities has garnered significant attention in practical applications. However, achieving these desired qualities simultaneously poses a significant challenge. This study introduces a single‐step calcination and chemical polymerization process to obtain an environmentally friendly ant‐nest‐inspired hybrid composite by optimizing conductive polypyrrole nanotubes (PNTs) within a 3D carbonaceous structure. The biomimetic composite forms a highly efficient conductive network, providing a pathway for free electrons within the carbonaceous barriers and enhancing the conduction loss. Remarkably, the EMWA performance of the composite achieves ultrathin (1.6 mm), wide effective absorption band (5.4 GHz), and strong absorption intensity (−67.6 dB) features. Moreover, due to the complex and intertwined 3D continuous network, the obtained samples exhibit excellent thermal insulation and superhydrophobic behavior by inhibiting heat transfer and preventing localized areas from being prone to water absorption. These findings not only offer a sustainable and low‐cost production route for biomimetic carbonaceous composites but also demonstrate a high‐efficiency absorber with great multifunctionality as a green alternative to traditional EMWA materials.

Carbon skeleton dispersed nano-jarosite for efficient Cr (Ⅵ) degradation: A bioinspired MFC cathode catalyst

Relevant advancements in microbial fuel cells (MFCs) are impeded by the limited oxygen reduction reactions at the cathode. The challenge prompted the development of a jarosite-biochar catalyst using a straightforward biomineralization method. Through X-ray diffraction (XRD) and scanning electron microscope (SEM) analysis, we observed a reduction in the agglomeration phenomenon of nano jarosite and a decrease in particle size. The biochar-jarosite MFC demonstrated a significant increase in voltage (682.5 mV) and a maximum power density of 1211 mW/m2. Electrochemical impedance spectroscopy (EIS) showed that the charge transfer resistance of the cathode decreased from 2580 Ω to 111 Ω, demonstrating excellent oxygen reduction reaction (ORR) performance. The jarosite-biochar significantly enhanced the MFC degradation of Cr (VI), exhibiting a 5.2-fold increase, while demonstrating exceptional stability. The X-ray photoelectron spectroscopy (XPS) of Fe and Cr on the surface of jarosite-biochar further substantiates the role of jarosite as an electron mediator between biochar and Cr (VI) in the MFC. Our study presents a cost-effective and efficient biomineralization strategy for the modification of cathode materials in MFCs, offering significant potential for enhancing the catalytic performance of iron-containing carbonaceous composites in Cr (VI) environments.

Electrophoretically Deposited Na3V2(PO4)3 and its Carbonaceous Composites as Promising Cathode for Sodium-ion Batteries

Sodium vanadium phosphate (NVP), a sodium ion super ionic conductor (NASICON), is one of the most attractive cathode materials for sodium ion batteries (SIBs). Electrophoretic deposition (EPD) is demonstrated to be an efficient synthesis tool to deposit strongly adhered and porous NVP carbonaceous material (viz. carbon nano tube (CNT) and reduced graphene oxide (rGO)) on aluminum current collector. EPD grown NVP delivers a stable reversible capacity ∼53.7 mAhg−1 at 0.1Ag−1 current density after 250 cycles. The introduction of CNT and rGO in the electrode significantly improves the electrochemical properties of NVP by providing better conduction pathways. Consequently, reversible capacities of 87 mAhg−1 and 70 mAhg−1 were obtained after 250 cycles at 0.1Ag−1 for NVP/RGO-CB and NVP/CNT-CB electrodes, respectively. These electrodes are able to deliver specific capacities of ∼70 mAhg−1 at a current density of 5Ag−1. Moreover, these electrodes were able to retain more than 80% of its initial capacity even after 2000 cycles at a high current density of 3Ag−1.

Different peroxymonosulfate activation and utilization pathways of typical cobalt oxides, cobalt-carbon and carbonaceous composites derived from metal-organic frameworks for pollutant oxidation in wastewater

Cobalt-based persulfate activation system has attracted increasing interests in recent years. However, few studies have focused on the corresponding relationship between different types of catalysts and peroxymonosulfate (PMS) utilization pathway in PMS activation process. To unravel this, three typical cobalt-based catalysts derived from ZIF materials (metal oxides ZMs, metal–carbon composite ZMCs, and etching metal–carbon composite ZCs) were applied in PMS activation system, and acetaminophen (APAP) was used as target contaminant. Quenching experiments and electron paramagnetic resonance (EPR) investigation testified that SO4·− were considered as the dominant reactive oxygen species (ROS) in the ZMs/PMS system, whereas non-radical pathway was dominant in the ZMCs/PMS and ZCs/PMS system. More Co-N species in ZMCs promoted the adsorption of PMS molecules and the formation of metastable PMS-catalyst complex. Electrochemical analysis proved that the improved intrinsic redox potential of metastable PMS-catalyst complex was due to the strong combination of PMS with positively charged Co-N species, resulting in the mass consumption of PMS. In addition, the CoⅣ=O species were mainly generated from single atomic Co or encapsulated Co sites in ZMCs and ZCs. Major degradation intermediates of APAP were detected by liquid chromatograph mass spectrometer (LC-MS) and differences in degradation pathway in three reaction systems were proposed. This study provides new insight into the PMS utilization mechanism during PMS activation process and offered environmentally friendly catalytic process for the degradation of pharmaceutical contaminants in wastewater.

In Situ Synthesis Method of Approaching High Surface Capacity Sulfur and the Role of Cobalt Sulfide as Lithium–Sulfur Battery Materials

Lithium–sulfur batteries (Li–S) are potentially applicable in electrification and the replacement of fossil fuels due to the high energy density and the economy of sulfur. However, effectively an insulator, sulfur is known to suffer from inert electrochemical and poor conductivity. By synthetically incorporating conductive, low‐dimensional carbonaceous composites acting as both containment hosts and catalysts to active materials, this work entails an effective and straightforward materials engineering approach in fundamentally remodeling active materials utilization and activation. This synthetic‐based approach highlights direct processing capabilities than traditional thermal infusion processes without compromising performance and addresses the low activation, poor conductivity as well as alleviating side reactions due to polysulfide species. Motivated by recent efforts in excellent catalytic properties of cobalt sulfide (CoS)‐based materials, in this work, high‐performance CoS‐based carbonaceous composites are designed and employed, alleviating side reactions. These sulfide‐based catalysts are further elucidated in their role in facilitating charge/discharge of active materials, and assessed on practical polysulfide and side reaction alleviation with respect to various discharge/charge states. Proof‐of‐concept devices demonstrate the following performance highlights: 1) high‐performance stability, 2) strong polysulfide adsorption capability and kinetic characteristics, 3) large and workable areal capacity, and active materials loading.

Phase and orientation effects in X-ray attenuation of carbonaceous epoxy composites

Composites made of carbon nanotubes (CNTs) reinforced in an epoxy matrix have already been successfully used as electromagnetic interference shielding materials. Different weight fractions of randomly distributed and vertically aligned multiwall carbon nanotubes (MWCNTs), graphite, and carbon fiber reinforced in the epoxy matrix were used to make these composites. The comparisons of percentage attenuation of different composite materials were studied under both diagnostic or hard (narrow beam geometry) and soft X-rays (monochromatic X-rays beam). It was found that the concentration of CNTs and graphite in epoxy composites affects attenuation. The results also demonstrate that the percentage attenuation for CNTs (as made) epoxy composite is always higher than graphite epoxy and treated CNTs epoxy composite at any concentration at the same thickness and tube voltage. This study also confirmed that the metal catalyst particles present in CNTs contribute to a considerable attenuation of X-rays along with CNTs and also demonstrated that the increase in metal content inside CNTs increases the attenuation. For hard X-rays, the orientation of CNTs in composites affects attenuation, and this effect gradually weakens at higher tube voltages. Vertically aligned carbon nanotubes (VACNT) array epoxy, and the thin composites are not suitable to attenuate diagnostic X-rays coming from high tube potential. For thin samples, VACNT array epoxy composites always perform better on attenuation of soft X-rays than randomly oriented CNTs in composites with any other composition lower than 15 wt %. This study also showed that there is a difference in the attenuation of soft X-rays amongst CNTs, graphite, and carbon fiber epoxy composites, which confirms that the attenuation depends on the geometry of the carbon structures. There is a clear effect of the orientation of CNTs in VACNTs epoxy composite on soft X-ray attenuation, and it shows that the radial direction of CNTs attenuates more X-ray radiation than the tube axis direction.

Solvothermal synthesis of g-C3N4 nanosheets modified carbon quantum dots for enhanced photocatalytic degradation

The incorrect disposal of industrial waste water has caused widespread concern of researchers due to its serious harm to people's health and ecological environment. Photocatalytic technology is widely used for wastewater purification owing to its simple operation, no secondary pollution and clean energy. In this study, carbonaceous composites were constructed by combining graphite-phase carbon nitride (g-C3N4) nanosheets with carbon quantum dots (CQDs) via hydrothermal method. The size of CQDs was about 8 nm, distributing over the surface of g-C3N4 nanosheets, and the existence of their interface interaction was confirmed. The photocatalytic degradation of methyl orange (MO) is considered to appraise the photocatalytic performance of the g-C3N4/CQDs composites under visible light. The obtained composites display better photocatalytic activity than the pure g-C3N4 nanosheets. The obtained g-C3N4/CQDs composite (CN-20) from 20 mL of the CQDs solution (∼1 mg mL−1) and 20 mg of g-C3N4 nanosheets displays the excellent photo-degradation efficiency and its apparent rate constant (kapp) is 4.0 times that of g-C3N4 nanosheets. In addition, CN-20 exhibits almost negligible influences of real environmental (pH value, inorganic anions, humic acid and source of water) on the degradation of MO, indicating potential in practical application. Furthermore, the g-C3N4/CQDs composite shows the enhanced cycle stability and the postulated mechanism of MO photocatalytic degradation is illustrated in detail.

Layered SnSe functionalized carbon composite as high-performance supercapacitor electrode

Metal chalcogenides and carbonaceous composites have triggered enormous interest in the field of high-performance supercapacitors due to their lower electrical resistance and high specific capacitance. Herein, nanocomposites between Sn, Se, and SnSe argan-derived carbon were prepared via a simple hydrothermal process. The porosity and the electrochemical activity of carbon were enhanced by the incorporation of SnSe into the carbon matrix. These materials were employed as supercapacitor electrodes in a symmetric configuration using 6 M KOH as electrolyte. The galvanostatic charge-discharge (GCD) test revealed that AC/SnSe has the highest specific capacitance of 341 F·g–1 at a current density of 1 A·g–1. While the EIS measurements showed that the equivalent series resistance dropped from 11.8 Ω for AC to just 0.69 Ω in the case of AC/SnSe which explains its excellent electrochemical performance. Moreover, the stability test showed excellent stability for AC/SnSe with a capacitance retention of 96% after 5000 cycles was achieved. In addition, the AC/SnSe electrode delivered an energy density of 45.5 W h Kg–1 at a power density of 54.3 W Kg–1. The excellent performance of AC/SnSe electrode can be attributed to its high surface area, large pore volume, and its layered structured that enhances the ionic adsorption.These findings suggest that the prepared AC/SnSe nanocomposite seems to be feasible as electrode material in the supercapacitor field or any related electrochemical application.

Single and double-layered Tri-band Microwave absorbing materials

Absorbers at microwave frequencies with multiple frequency-band response are particularly important for use in military for stealth technology. Specially, ferrite based absorbing materials are significant for electromagnetic shielding and signal attenuation. The enhancement of reflection loss of ferrites along with carbonaceous materials are even more beneficial. Recently double-layer absorbers have extensively studied to meet the requirements of advanced absorbing materials in multiple frequency-band response. It still remains a challenge how to determine the type and thickness to couple the impedance-matching-layer to the absorption-layers for a double-layer absorber. We applied hydrothermal method to prepare Fe3O4 nanoparticle and combine them with either graphene oxide (GO) or reduced graphene oxide (rGO) to prepare a composite of specific quality to obtain Fe3O4@GO and Fe3O4@rGO nanocomposite. We studied microwave attenuation capabilities of single and double-layer absorbers containing these two materials. We have demonstrated that with a thin impedance matching layer as a first layer and an absorbing layer behind this layer for the double-layered absorber has much higher reflection loss (RL) than a single-layer. The Fe3O4@rGO composite as a single-layer absorber shows the best microwave absorption performance with RL close to −30 dB in all three microwave bands (X, Ku and K bands). The use of a double-layer structure as Fe3O4@GO as impedance matching layer and Fe3O4@rGO as absorbing layer exhibits the best absorption of −50 dB. This is much larger than the single-layered absorbers at all three frequency-bands. Such a performance is superior to many reported ferrite-based carbonaceous composites. Therefore, a double-layer absorber is best suited to coat the whole body of the aircraft or missiles to evade satellite detection, a preparation towards new-generation weapons for future warfare. Before performing the absorption studies we have characterized the ferrites, GO and rGO materials with various microstructural and magnetic characterizations.

A Review on Graphene (GN) and Graphene Oxide (GO) Based Biodegradable Polymer Composites and Their Usage as Selective Adsorbents for Heavy Metals in Water.

Water pollution due to heavy metal ions has become a persistent and increasing problem globally. To combat this, carbonaceous materials have been explored as possible adsorbents of these metal ions from solution. The problem with using these materials on their own is that their lifespan and, therefore, usability is reduced. Hence the need to mask them and an interest in using polymers to do so is picked. This introduces an improvement into other properties as well and opens the way for more applications. This work gives a detailed review of the major carbonaceous materials, graphene and graphene oxide, outlining their origin as well as morphological studies. It also outlines the findings on their effectiveness in removing heavy metal ions from water, as well as their water absorption properties. The section further reports on graphene/polymer and graphene oxide/polymer composites previously studied and their morphological as well as thermal properties. Then the work done in the absorption and adsorption capabilities of these composites is explored, thereby contrasting the two materials. This enables us to choose the optimal material for the desired outcome of advancing further in the utilization of carbonaceous material-based polymer composites to remove heavy metal ions from water.

A Short Review on Nanostructured Carbon Containing Biopolymer Derived Composites for Tissue Engineering Applications.

The development of new scaffolds and materials for tissue engineering is a wide and open realm of material science. Among solutions, the use of biopolymers represents a particularly interesting area of study due to their great chemical complexity that enables creation of specific molecular architectures. However, biopolymers do not exhibit the properties required for direct application in tissue repair-such as mechanical and electrical properties-but they do show very attractive chemical functionalities which are difficult to produce through in vitro synthesis. The combination of biopolymers with nanostructured carbon fillers could represent a robust solution to enhance composite properties, producing composites with new and unique features, particularly relating to electronic conduction. In this paper, we provide a review of the field of carbonaceous nanostructure-containing biopolymer composites, limiting our investigation to tissue-engineering applications, and providing a complete overview of the recent and most outstanding achievements.

Rice husk char as a sustainable material for the preparation of graphene oxide-supported biocarbons with mesoporous structure: A characterization and adsorption study

Rice husk (RH) is a biomass-based waste that can be used to produce sustainable energy. RH carbon (RHC) and RH ash (RHA) remain in solid char after the transformation of RH into heat energy. To effectively use RHC and RHA wastes, this study proposed using two graphene oxide (GO)-based carbonaceous composites: RHC/GO and ordered mesoporous carbon (OMC)/GO. RHC was prepared through the high-temperature pyrolysis of RH. OMC was obtained by recycling RHA as a silica template source. The experimental results demonstrated that surface areas and pore volumes of carbonaceous composites were increased after the addition of GO. Both RHC/GO and OMC/GO materials exhibited a mesoporous structure with a surface area of 618 and 1068 m2/g, respectively, and a pore volume of 0.533 and 1.143 cm3/g, respectively. Rhodamine B (RhB) was used to evaluate the effects of solution pH, adsorbent dosage, and the initial concentration of the relevant dye on the adsorption capacities of the two carbonaceous composites. OMC/GO had a relatively satisfactory performance for the elimination of RhB compared with RHC/GO. The findings of kinetics and isothermal adsorption studies for RHC/GO and OMC/GO implied that adsorption obeyed the pseudo-second-order and Langmuir models. RHC and RHA can be beneficial for synthesizing nanoproducts and reducing biowastes.

Novel hybrid coating of TiN and carbon with improved corrosion resistance for bipolar plates of PEM water electrolysis

Surface modification of Ti based bipolar plates (BPs) could be an effective solution to prevent the formation of low-conductive oxide film, promote the corrosion resistance and electronic conductivity as well. In this work, a novel hybrid coating composed of nano-sized TiN and carbonaceous phases (TiN–C) was successfully established on a Ti substrate via a combined electrophoretic deposition and thermal treatment process. Various physiochemical characterizations revealed that the coating was uniform, and the formation of the nano-sized TiN and carbonaceous composites reduced the interfacial contact resistance significantly. The potentiodynamic and potentiostatic polarization tests indicated that the hybrid coating TiN–C prepared at 400 °C had a corrosion current density of only 1.41 μA cm−2, which was an order of magnitude lower than that (36.02 μA cm−2) of the bare Ti. Furthermore, the as-prepared coating showed excellent durability in both the simulated PEMWE environment and the PEMWE cell under polarization at 1.7 V for more than 300 h.

Hybrid carbonaceous adsorbents based on clay and cellulose for cadmium recovery from aqueous solution.

The current work describes the synthesis of carbonaceous composites via pyrolysis, based on CMF, extracted from Alfa fibers, and Moroccan clay ghassoul (Gh), for potential use in heavy metal removal from wastewater. Following synthesis, the carbonaceous ghassoul (ca-Gh) material was characterized using X-ray fluorescence (XRF), Scanning Electron Microscopy coupled with Energy Dispersive X-ray (SEM-EDX), zeta-potential and Brunauer-Emmett-Teller (BET). The material was then used as an adsorbent for the removal of cadmium (Cd2+) from aqueous solutions. Studies were conducted into the effect of adsorbent dosage, kinetic time, initial concentration of Cd2+, temperature and also pH effect. Thermodynamic and kinetic tests demonstrated that the adsorption equilibrium was attained within 60 min allowing the determination of the adsorption capacity of the studied materials. The investigation of the adsorption kinetics also reveals that all the data could be fit by the pseudo-second-order model. The Langmuir isotherm model might fully describe the adsorption isotherms. The experimental maximum adsorption capacity was found to be 20.6 mg g-1 and 261.9 mg g-1 for Gh and ca-Gh, respectively. The thermodynamic parameters show that the adsorption of Cd2+ onto the investigated material is spontaneous and endothermic.

Pyrene-based covalent organic polymers with nano carbonaceous composites for efficient supercapacitive energy storage

We prepared Py-DSDA-COP/SWCNTs and this material showed a capacitance of 171 F g−1 and energy density of 23.7 W h kg−1 which is superior to those of Py-DSDA-COP/MWCNTs and Py-DSDA-COP/C60 nanocomposites.

Transforming in-situ grown chitosan/ZIF-67 aerogels into 3D N-doped Co/CoO/carbon composites for improved electromagnetic wave absorption

Nowadays there is much room for improvement in the designed synthesis of high-performance electromagnetic wave absorbers by combining metal-organic frameworks (MOFs) and biomass components. Herein, 3D N-doped porous carbon cobalt/cobalt oxide (NPC/Co/CoO) composites were successfully prepared by transforming in-situ grown ZIF-67 clusters on a chitosan matrix. Analysis results showed that the N-doped carbonaceous composites obtained had unique porosity, high specific surface area, and defect-enriched structure, which provided numerous paths for electron transfer, leading to big benefits to interfacial polarization and dipole polarization. Most importantly, the ferromagnetic resonance and magnetic coupling were enhanced by ZIF-67-derived Co/CoO nanoparticles. By adjusting the content of metallic cobalt salt, pyrolysis temperature, and sample filling content, the optimal impedance matching properties of the composites could be optimized. When the matching thickness is 2 mm, the RLmin of NPC/Co/CoO-10/700–30 wt% achieved − 48.97 dB at 13.52 GHz, and the effective absorption bandwidth exceeds 5.36 GHz. The composites with excellent performance prepared by a controllable process using chitosan and ZIF-67 might be a promising alternative for the large-scale preparation of high-frequency electromagnetic wave absorbers.

Activation of peroxymonosulfate by cobalt-embedded carbon aerogels: Preparation and singlet oxygen-dominated catalytic degradation insight

Carbonaceous catalytic composites mediated peroxymonosulfate-based advanced oxidation processes (PMS-AOPs) have received extensive attention for efficient organic pollutants remediation, due to the recognized advantages in contrast to the traditional Fenton-like process. In parallel, biomass was widely used in the environmental field as an important precursor of carbonaceous materials. Herein, cobalt-embedded carbon aerogels were prepared using lotus root starch as a precursor and employed as an efficient activator for PMS for carbamazepine degradation. Its excellent PMS activation performance could be attributed to the following synergistic factors: i) The hierarchical pore structure and large surface area of carbon aerogels could promote the fixed distribution of metal particles, reduce particle aggregation and metal leaching, increase active sites and facilitate the mass transfer process; ii) Carbon aerogels could efficiently activate PMS through active sites on the surface (such as defect structures, sp2-hybridized carbons, oxygen-containing functional groups, metal species, etc.); iii) The degradation of carbamazepine was promoted by π-π interaction and hydrogen bonding as the adsorption mechanism. Mechanistic studies showed that singlet oxygen (1O2) played a dominant role in the degradation of carbamazepine. In addition, the electrochemical analysis indicated that the electron transfer mechanism was also an efficient pathway in the Co-CA-900/PMS system. Overall, this study might provide new insights into the rational design and application of transition metal-embedded carbon aerogels for PMS activation in environmental remediation.

Enhanced electrical conductivity of pitch-derived carbon via graphene template effects for high electrically conductive composites

Large-scale preparation of cheap and high-performance carbonaceous materials is in urgent need due to the huge demand of carbonaceous materials-organic binder composites for Joule heating. Here, carbon-based electrothermal composites with high electrical conductivity were fabricated by adjusting the morphology and structure of pitch-based carbonaceous materials (PC) through the use of graphene as structure-directing agent to tune the orientation and carbonization of coal pitch. It is demonstrated that the addition of graphene can effectively promote the formation of graphitized carbon, increase the content of sp2C, reduce defective carbon and increase the graphite interlayer spacing. 1% graphene-added PC-PVDF composite exhibits 290% increase in the carrier concentration, 190% enhancement in mobility, and 67% reduction in the volume resistivity compared to PC-PVDF composite. Molecular simulations elucidate that the graphene edges favor pitch carbonization and improve the orientation factor and energy gap of carbon materials. This study provides clues for design of low-cost pitch-derived carbon materials-binder composites.

Kinetically accelerated lithium storage in dumbbell-like Co/Cu@CN composite derived from a bimetallic-organic framework

Compared with single-component anode materials with obvious shortcomings, multi-component structured carbonaceous composites are expected to possess higher electrochemical activity and fast diffusion kinetics. Therefore, they show promising prospects in electrochemical energy storage applications. However, their synthesis is also challenging. Here, we report the preparation of dumbbell-shaped rod-like N-doped bimetallic CuCo carbonaceous composites (Cu/Co@CN) as high-performance anode materials for lithium storage using a bimetal-organic framework (MOF)-derived synthesis method. This unique dumbbell-shaped rod-like structure obtained by a facile solid-state sintered metal-organic framework can effectively withstand volumetric strain and can be beneficial towards structural stability. Highly dispersed Cu/Co and carbonaceous materials exert compositional synergistic effects to improve electrical conductivity and lithium-ion storage capacity, in turn enhancing the electrochemical activity. Abundant N doping and dumbbell rod structure provide additional active sites for directing Li reactions and accelerating ion/electron mobility. The results show that Cu/Co@CN-500 exhibits outstanding electrochemical performance, including remarkable specific capacity (1115.3 mAh g−1 at 200 mA g−1), extraordinary rate performance (419.5 mAh g− even at 2 A g−1) and good cycling stability (545.4 mAh g−1 upon 750 cycles at 1000 mA g−1). These bimetallic carbonaceous composites with ideal structure, composition, and properties showed a great potential towards being qualified as anode candidates for advanced lithium storage.