Two-dimensional Carbon Nanomaterials Research Articles

From BN-Doped Molecular Carbon Scaffolds to BNC Sheets

In carbon nanoscience, the on-surface synthesis strategy emerged as a promising route to achieve structural control at the atomic scale. This approach might be applied to fabricate well-defined two-dimensional BN-substituted carbon nanomaterials with tunable electronic properties [1]. In this talk, I will review our activities on the self-assembly of BN-doped molecular precursors, including borazine [2] and BN-doped carbon scaffold [3], on noble metal supports. Temperature-induced dehalogenation and dehydrogenation reactions are applied to introduce intramolecular ring-closing and intermolecular coupling, e.g., yielding random BNC sheets, probed by low-temperature scanning tunneling microscopy and X-ray photoelectron spectroscopy. The potential transfer and characterization of such two-dimensional BNC materials in devices will be discussed.[1] Sánchez-Sánchez et al., ACS Nano 9, 9228 (2015)[2] Weiss et al., Adv. Mat. Interfaces, accepted, doi: 10.1002/admi.202300774[3] Schwarz et al., Chem. Eur. J. 24, 9565 (2018)

Lexible sensors for food monitoring. Part II: Applications

Monitoring and maintaining food quality, safety, and authenticity are the most important concerns in the food industry. The cutting-edge flexible sensors for food monitoring precisely satisfy the needs of acquiring information on multiple parameters in a small space, they provide for the more reasonable layout, get data on the mechanical deformations, and can be conformably attached to arbitrarily curved surfaces. The flexible sensing materials with a large area of specific surface, that ensure high mobility and density of the media, feature dense active sites, outstanding adjustability and high processing capacities, such as two-dimensional carbon nanomaterials, conductive polymers, and nano-hybrid materials; those materials have further improved the sensitivity, stability and selectivity of the flexible sensors’ perception. This article attempts to critically review the present state-of-arts developments in relation to the materials, manufacturing techniques and sensing mechanisms of the devices, as well as the applications of the electrically-transduced flexible sensors. Moreover, this article elaborates on the transduction mechanisms of the several typical transducers, with a focus on the physics behind, including the modulation of the doping level, Schottky barrier, and interfacial layer that typically cause changes in conductivity, functionality and permittivity. We also highlight the benefits and the technical challenges along with the appropriate solutions provided by the presented flexible sensors, and we also consider the potential strategies that allow overcoming limitations in power consumption, quantitatively assess the trade-offs in maintaining the quality and marketability, to optimize wireless communication and explore new sensing patterns.

Tube-on-rod structure of MWCNTs-ammonium cobalt vanadium oxide/ammonium vanadium oxide; evaluation of electrochemical hydrogen storage capacity

Carbon nanostructures have lately been widely used in energy storage systems. This study examines the impact of ammonium cobalt vanadium oxide/ammonium vanadium oxide as electrode materials in hydrogen storage which modifying with carbon nanostructures. The poor conductivity of vanadate-based materials may be improved by adding zero to two-dimensional carbon nanomaterials, such as graphene quantum dots (GQDs), graphene oxide (GO), and multiwall carbon nanotubes (MWCNTs). Electrode materials based on (NH4)2V12O27·xH2O/(NH4)2Co2V10O28·16H2O/NH4V3O8 were synthesized by hydrothermal method in the presence of PEG with engineered morphology of one dimensional (ID) nanorods. The carbonous nanocomposites based on GQDs, MWCNTs and GO exhibit a capacity 203, 438 and 28 mAhg−1 after 15 cycles at a current density of 1 mA. The hydrogen storage performance is influenced by various amount of MWCNTs. Increasing the percentage of MWCNTs led to decreasing the capacity. Therefore, optimum electrode materials fabricated in the presence of 5 % MWCNTs which has 1055 mAhg−1 capacity. Therefore, 1D/1D structure of Tube-on-Rod can improve the performance of hydrogen storage in the ammonium cobalt vanadium oxide/ammonium vanadium oxide electrodes.

Flexible sensors for food monitoring. Part I: Principle

Monitoring and maintaining food quality, safety, and authenticity are the most important concerns in the food industry. The cutting-edge flexible sensors for food monitoring precisely meet the needs of acquiring information on multiple parameters in small space and more reasonable layout, providing data on mechanical deformations, and conformably attaching to arbitrarily curved surfaces. Flexible sensing materials with a large specific surface area, high carrier mobility and carrier density, dense active sites, outstanding tunability, and processability, such as two-dimensional carbon nanomaterials, conductive polymers, and nanohybrid materials, have further improved the sensitivity, stability, and selectivity of flexible sensors. This article attempts to critically review state-of-the-art developments with respect to materials, fabrication techniques, and sensing mechanisms of devices, as well as the applications of the electrically-transduced flexible sensors. In addition, this review elaborates on the transduction mechanisms of several typical transducers, with a focus on the physics behind, including the modulation of doping level, Schottky barrier, and interfacial layer that typically lead to changes in conductivity, work function, and permittivity. We also highlight the benefits, technical challenges with corresponding solutions of current flexible sensors, and discuss potential strategies to overcome limitations in energy consumption, quantify the trade-offs in maintaining quality and marketability, optimize wireless communication, and explore new sensing patterns.

Yolk-shell structure synergistic defect engineering for boosting electromagnetic wave absorption in Co9S8@Humins-derived carbon

Exploring new strategies to incorporate the concepts of green chemistry and defect engineering into new architectures to address the problem of severe electromagnetic wave (EMW) pollution is challenging. In this work, by using a by-product of catalytic conversion of biomass as a carbon source, we prepare two-dimensional (2D) Co9S8-coated humins-derived carbon nanomaterials with a yolk-shell structure. The EMW attenuation ability is finally optimized by controlling the morphology and defects of the composite material through the pyrolysis temperature. As expected, with the synergy of conductive loss/interfacial polarization and defects regulating, the composite material achieves a reflection loss (RL) value of −51.4 dB in Ku-band and the effective absorption bandwidth (EAB) can be as high as 5.92 GHz (12.08–18.00 GHz) at 1.8 mm ultra-thin coating thickness. A strong absorption capacity in the low-frequency C-band (6.4 GHz) reaches RL value of −49.9 dB and a thickness of 3.50 mm, which grants it the characteristic of convertible microwave absorption from high frequency to low frequency. Taking account of the facile synthesis and tunable absorption properties, the encouraging findings shed light on exploring waste-turned-microwave absorbents with promising practical applications.

Effects of Graphene Morphology on Properties of Carbon Nanotube/Polyurethane Film Strain Sensors

The film flexible sensors can convert tiny changes in size or force into electrical signals. They are key components of intelligent devices and wearable devices, and are widely used in human-computer interaction, electronic skin, health monitoring, implantable diagnosis, and other fields. This kind of sensor is generally composed of polymer matrix and conductive components, while carbon nanotubes (CNT) and graphene (GN), as typical one-dimensional and two-dimensional conductive carbon nano-materials, respectively, have been used to build film flexible sensors. In order to explore the relationship between the GN size and thickness, and the performance of film sensors, the GN-CNT/PU composite film sensors were prepared by in situ polymerization of polyurethane (PU) in the presence of GN and CNT. A highly sensitive GN-CNT/PU flexible film sensor was prepared with a high gauge factor (GF) up to 13.15 in a strain range of 0–20%; an exceptionally low percolation threshold of GN is about 0.04 vol% when the CNT content is fixed at 0.2 vol%, which is below the percolation threshold of CNT/PU nanocomposites. The size of the GN layer affects the GFs of the flexible film sensors; a GN with a smaller size can achieve a greater GF. This study paves the way for the better application of different qualities of GN in flexible sensors.

Potential reversible hydrogen storage in Li-decorated carbon allotrope PAI-Graphene: A first-principles study

Two-dimensional porous carbon nanomaterials are proven to be promising hydrogen storage substrates as they possess high surface area, large number of active sites, low molecular mass, and hydrogen molecules can be adsorbed on both sides of these materials. By performing first-principles density functional theory-based calculations, we report ultrahigh reversible hydrogen uptake in lithium decorated 2D carbon allotrope PAI-graphene, which is formed of a regular pattern of polymerized as-indacenes (PAI). We found that a single unit cell of PAI-graphene can be decorated by 8 Li atoms, in which each Li atom can reversibly adsorb 4 hydrogen molecules, leading to 15.7% of H uptake, remarkably higher than the DOE demand of 6.5%. Li atom donates its valence 2s-electron to PAI-graphene and gets ionized. The adsorption energies of the various H2 attached to Li-atom are found to be suitable for reversible use during practical applications. Hydrogen molecules get attached to the ionized metal atom by electrostatic interactions. An energy barrier of 1.48 eV is present for the diffusion of Li atoms between the two most stable adsorption sites which justifies the absence of the clustering of Li atoms.

Preparation of Graphene Nanosilver Composites for 3D Printing Technology

At present, graphene in two-dimensional carbon nanomaterials is a material with excellent properties. Its preparation technology and application prospects are very wide. The most common one is the chemical redox method, which can make graphite into graphite oxide dispersed in water. Graphene oxide obtained by the Hummers method has a wrinkled structure. In order to broaden the application field of graphene and give full play to its excellent properties, the current research on graphene mainly focuses on the preparation and application of functional composite materials as a matrix material or reinforcement material. Due to its special two-dimensional structure, it has a large specific surface area, good biocompatibility, and stable physical and chemical properties, making it an excellent nanoparticle carrier. The graphene-supported silver nanoparticles can effectively prevent the aggregation and stacking between particles, improve the electrochemical performance of the composite material, and expand its application range. In this article, the assisted preparation of graphene nanosilver composites by 3D printing technology (three-dimensional printing) was studied. 3D printing technology is a rapid prototyping technology that emerged in the 1980s. 3D printing technology is based on discrete stacking and realizes rapid processing of models by directly outputting data from the printing device. In this article, a new type of graphene oxide (GO) was prepared by the modified Hummers method. In the case of NaOH aqueous solution as a catalyst, silver nitrate and GO were used as precursors, and XRD, infrared spectrum, Raman spectrum, and other methods were used. The crystal structure and morphology of Ag/rGO under different conditions were studied, thus revealing the growth of silver particles and the changes of oxidized functional groups under different conditions. It was found that the intensity of the two peaks in the GNs-Ag-2 Raman spectral curve was seven times that of the GNs peak.

Synthesis of γ-graphyne by modified mechanochemistry with enhanced adsorption of organic dyes

The γ-graphyne is a new two-dimensional carbon nanomaterials with unique sp and sp2 hybridized carbon atoms, uniform distribution of nanotopological pores, and high degree of π-conjugation, making it a promising candidate in water pollutant treatment. Herein, γ-graphyne was synthesized by a modified mechanochemical method and used as adsorbents for removing of organic dyes. Raman spectra, X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) are performed to confirm the chemical structure and morphology of γ-graphyne. The maximum adsorption capacities of γ-graphyne for rhodamine B (RhB), methylene blue (MB) and congo red (CR) obtained through kinetic and isotherm analysis are 386.10, 357.14 and 254.45 mg/g, respectively，which are in good accordance with the experimental results of 383.64, 359.72 and 242.44 mg/g. The calculated adsorption energies of −20.0995, −12.5219 and −8.3647 kCal/mol, respectively, for RhB, MB and CR, which characterized the possible adsorption sites, give more deep understanding of the experimental results regarding the remarkable absorbability of γ-graphyne. Our work sheds light on synthesis of γ-graphyne for the future development of excellent adsorbents.

Graphene Oxide and Fluorescent-Aptamer-Based Novel Aptasensors for Detection of Metastatic Colorectal Cancer Cells.

Early diagnosis of metastatic colorectal cancer (mCRC) is extremely critical to improve treatment and extend survival. W3 is an aptamer that can specifically bind to mCRC cells with high affinity. Graphene oxide (GO) is a two-dimensional graphitic carbon nanomaterial, which has widely used in constructing biosensors. In this study, we have developed a no-wash fluorescent aptasensor for one-step and sensitive detection of mCRC LoVo cells. It is based on fluorescence resonance energy transfer (FRET) between GO and the W3 aptamer labeled with 5-carboxyfluorescein (FAM). GO can quench the green fluorescence of the FAM-labeled W3 (FAM-W3). In the presence of the target cells, FAM-W3 preferentially binds the target cells and detaches from the surface of GO, leading to the fluorescence of FAM recovery. It was demonstrated that the fluorescence recovery increases linearly in a wide range of 0~107 cells/mL (R2 = 0.99). The GO-based FAM-labeled W3 aptasensor (denoted as FAM-W3-GO) not only specifically recognizes mCRC cell lines (LoVo and HCT116), but also sensitively differentiates the target cells from mixed cells, even in the presence of only 5% of the target cells. Furthermore, FAM-W3-GO was applied to detect LoVo cells in human whole blood, which showed good reproducibility with an RSD range of 1.49% to 1.80%. Therefore, FAM-W3-GO may have great potential for early diagnosis of mCRC. This strategy of GO-based fluorescent aptasensor provides a simple, one-step, and highly sensitive approach for the detection of mCRC cells.

A sustainable and low-cost route to prepare magnetic particle-embedded ultra-thin carbon nanosheets with broadband microwave absorption from biowastes

Two-dimensional (2D) carbon nanomaterials have attracted extensive attention in the field of microwave absorption (MA) owing to their unique layered structure, tailorable atomic layer, tunable active surface, and high dielectric loss. Here, novel porous graphene-like heterostructures are facilely prepared through the carbonization of pomelo peel (PP)/prussian blue (PB) and PP/PB analogues (PBA). The magnetic particles derived from PB and PBA are uniformly distributed in the N-doped carbon (NC) ultra-thin nanosheets, which enhances the magnetic loss and improves the interfacial polarization. The optimized Fe/ZnO/NC-7 sample exhibits a maximum reflection loss (RLmax) of −58.12 dB at 2.05 mm, and an ultrabroad effective bandwidth (RL ≤ −10 dB) of 7.6 GHz is achieved at 1.9 mm, which covers nearly half of the measured frequency range. The superior MA performance of Fe/ZnO/NC-7 composite is ascribed to the unique magnetic particle-embedded carbon nanosheet, which not only optimizes the impedance matching but also enhances the electromagnetic wave (EMW) attenuation ability through 2D conductive networks and multiple polarization processes. Overall, this work offers an environmentally friendly method to prepare low-cost and high-performance microwave absorbers from biowastes, which exhibit superior application potential as compared to other 2D microwave absorbers including graphene and MXene.

Electrochemical sensing performance of nitrogen rich zero- and two-dimensional carbon nanomaterials modified electrodes towards purines catabolism

Electrochemical sensing of uric acid (UA) by using nitrogen-rich carbon nanomaterials such as N-doped carbon dots (N-CDs), N-doped graphene quantum dots (N-GQDs) and graphitic carbon nitride (GCN) electrodeposited on screen printed carbon electrode (SPCE) was studied. These N-rich carbon materials were prepared by reported procedures and characterized by spectroscopic, XRD and SEM techniques. They were deposited on SPCE by potentiodynamic electrodeposition from -0.2 to +1.7 V. The topographical studies by SEM reveal that the dots like morphology of both N-CDs and N-GQDs was retained on SPC substrate whereas aggregated thin sheet like structure was noticed for the electrodeposited GCN. Then, the electrochemical sensing performance of these electrodes towards UA was studied. Among the different electrodes, SPCE deposited with GCN (SPCE/GCN) shows the highest oxidation current for UA due to its larger surface area and lower charge transfer resistance. Further, SPCE/GCN was exploited to determine UA in the presence of xanthine (XA), which was commonly present in blood serum. The amperometric method was deployed to determine UA from 0.2 to 1000 µM and achieved the limit of detection (LOD) of 24.4 nM (S/N=3) and sensitivity of 12.4 µA µM−1 cm−2. The practical application of SPCE/GCN was examined by quantifying UA in human blood serum sample and the obtained result was validated with the clinical method.

Fluorescent Biosensors for the Detection of Viruses Using Graphene and Two-Dimensional Carbon Nanomaterials

Two-dimensional carbon nanomaterials have been commonly employed in the field of biosensors to improve their sensitivity/limits of detection and shorten the analysis time. These nanomaterials act as efficient transducers because of their unique characteristics, such as high surface area and optical, electrical, and magnetic properties, which in turn have been exploited to create simple, quick, and low-cost biosensing platforms. In this review, graphene and two-dimensional carbon material-based fluorescent biosensors are covered between 2010 and 2021, for the detection of different human viruses. This review specifically focuses on the new developments in graphene and two-dimensional carbon nanomaterials for fluorescent biosensing based on the Förster resonance energy transfer (FRET) mechanism. The high-efficiency quenching capability of graphene via the FRET mechanism enhances the fluorescent-based biosensors. The review provides a comprehensive reference for the different types of carbon nanomaterials employed for the detection of viruses such as Rotavirus, Ebola virus, Influenza virus H3N2, HIV, Hepatitis C virus (HCV), and Hepatitis B virus (HBV). This review covers the various multiplexing detection technologies as a new direction in the development of biosensing platforms for virus detection. At the end of the review, the different challenges in the use of fluorescent biosensors, as well as some insights into how to overcome them, are highlighted.

Electromagnetic Wave Absorption and Mechanical Properties of CNTs@GN@Fe3O4/PU Multilayer Composite Foam.

With the development of intelligent communications and stealth technology in the military field, electromagnetic wave pollution cannot be ignored, and absorbing materials have entered people’s field of vision and gradually become a research hotspot. The ideal absorbing material should have the characteristics of “strong, wide, thin, and light”, but a single absorbing material often cannot meet the above conditions. At present, absorbing metal powder combined with two-dimensional carbon nanomaterials (such as carbon nanotubes, graphene, etc.) has became a trend. This article focus on a three-layer composite of Fe3O4, Carbon nanotubes@ Fe3O4, Carbon nanotubes@Graphene nano-platelets@ Fe3O4, which was synthesized by solvothermal method. The results show that the electromagnetic wave absorption performance of the three-layer foam at a thickness of 3.0 mm is more excellent. The minimum of RL can reach −67.0 dB, and the effective bandwidth is above 5.0 GHz. All this is due to the synergy of dielectric and magnetic loss between Fe3O4, CNTs, and GN, the increase of interface polarization and the path of electromagnetic wave reflection and scattering by three-layer foam.

Graphdiyne: from Preparation to Biomedical Applications.

Graphdiyne(GDY) is a kind of two-dimensional carbon nanomaterial with specific configurations of sp and sp2 carbon atoms. The key progress in the preparation and application of GDY is bringing carbon materials to a brand-new level. Here, the various properties and structures of GDY are introduced, including the existing strategies for the preparation and modification of GDY. In particular, GDY has gradually emerged in the field of life sciences with its unique properties and performance, therefore, the development of biomedical applications of GDY is further summarized. Finally, the challenges of GDY toward future biomedical applications are discussed.

Advances in the cytotoxic mechanism of nanomaterials graphene oxide

Graphene oxide is a novel two-dimensional carbon nanomaterial, but it has potential risks for the health of occupationally exposed workers. This article briefly reviews the research progress on the cytotoxic mechanism of graphene oxide and its derivatives in terms of oxidative stress, physical damage and dysfunction of enzyme activity. This review also discusses effective measures for the mitigation of cytotoxicity in order to provide helpful evidence for occupational health risk and biological safety assessment of graphene nanomaterials in China.

Application of Novel Hollow Carbon Nanosphere Drug-Loading System in Chemotherapy of Esophageal Squamous Cell Carcinoma.

With the continuous improvement of carbon nanotube synthesis and purification technology and the continuous improvement of carbon nanotube dispersion technology, carbon nanotubes have played an increasingly important role in the treatment of malignant tumours. One of the hot spots. Compared with other carbon nanotube materials, the carbon nanosphere drug loading system is more suitable for loading hydrophobic drugs, and the drug loading capacity is higher than other one-dimensional two-dimensional carbon nano-materials. In addition, carbon nanospheres of a suitable size are more easily absorbed by tumour cells and can carry a large amount of drugs for transport in the blood. And the pore structure of the carbon nanosphere is adjustable, and the drug release can be controlled by adjusting the pore size, and the pore diameter is generally less than 10 nm to prevent the drug from being released in advance. Esophageal cancer is one of the most frequently occurring malignancies in China, and the incidence of esophageal cancer ranks 8th in the world. Palliative chemotherapy is t he main treatment method for patients with advanced esophageal cancer. Simultaneous chemoradiotherapy has relatively obvious advantages in improving the survival rate of patients. It is of great significance to study the application of carbon nanosphere drug-loading system in chemoradiotherapy for esophageal squamous cell carcinoma. Therefore, in this study under the hydrothermal method, which is one of the commonly used methods for the synthesis of hollow carbon nanospheres, carboxymethyl chitosan was used as a carbon precursor, and the targeted drug erlotinib was loaded with carbon nanospheres. A new hollow nano-carbon sphere drug-loading system (HNCSDLS) was prepared and related characterizations were carried out. At the same time, the morphology, properties, in vitro and in vivo toxicity, bio-distribution, and anti-tumour activity of HNCSDLS were also studied in this study using scanning electron microscopy flow cytometry, laser confocal, spectrometer, cell proliferation experiment, and in vivo fluorescence imaging experiment Detection. The results of this study indicate that HNCSDLS has high biocom-patibility and stability, can be quickly distributed in the cytoplasm, and avoids lysosomal clearance. It can effectively deliver erlotinib to the tumour site, extend the drug's in vivo circulation time, inhibit tumour growth, reduce the toxicity of erlotinib to heart and kidney tissues, and increase its antitumor activity.

Promoting potential direct interspecies electron transfer (DIET) and methanogenesis with nitrogen and zinc doped carbon quantum dots

Although it has been demonstrated that one-dimensional, two-dimensional, and three-dimensional carbon nanomaterials can improve the CH4 production of anaerobic digestion (AD), the effect of zero-dimensional carbon nanomaterials on AD have not been reported. To expand the application of carbon nanomaterials in AD, the effect of zero-dimensional carbon nanomaterials-carbon quantum dots (CDs) on various feedstocks (c.a. cellulose, glucose, ethanol, and vinegar residue) were investigated in this study. Results have shown that CH4 yield from ethanol was increased by 24.59% (p = 0.396) after adding 5 g/L zinc doped carbon quantum dots (Zn-doped CDs) while that from vinegar residue was dramatically increased by 230% (p = 0.000) using 5 g/L nitrogen doped carbon quantum dots (N-doped CDs). In addition, photoluminescence demonstrated that CDs acted as a capacitor for transmitting and receiving electrons. Furthermore, co-occurrence network analysis revealed that Clostridiales might be used as a signal source to communicate with other species. This study firstly shifted the application of CDs from fluorescence to AD and manifested its positive impact on AD. In short, these findings provided a better understanding on the effects of CDs on different feedstocks of methanogenesis and revealed new evidence of stimulating methanogenesis via CDs.

Facile and template-free strategy to construct N, P co-doped porous carbon nanosheets as a highly efficient electrocatalyst towards oxygen reduction reaction

Abstract Two-dimensional (2D) porous carbon nanomaterials are of great interest for various applications in the field of energy conversion and storage. The development of efficient metal-free electrocatalysts for oxygen reduction reaction (ORR) with cost-efficient and simple approach still remains a significant challenge. Herein, we report a facile and template-free strategy to construct N, P co-doped porous carbon nanosheets (NPPC) by pyrolysis of calcium gluconate as carbon support and phosphonitrilic chloride trimer as the source N and P. The resultant NPPC, as metal-free electrocatalyst for ORR, exhibits outstanding electrocatalytic performance with a more positive half-wave potential of 0.87 V, longer durability and superior tolerance to methanol than those of commercial Pt/C in alkaline solution. Excellent ORR properties are contributed from the synergistic effect of abundant active sites of N, P and defects distributed in the carbon framework and 2D hierarchical pore morphology. Impressively, it is promising to inspire a general route for large-scale and facile synthesis of 2D porous carbon nanomaterials for application in new energy devices.

Rationally exfoliating chitin into 2D hierarchical porous carbon nanosheets for high-rate energy storage

Two-dimensional (2D) carbon nanomaterials with hierarchical porous structure and heteroatoms doping are highly desirable in the fields of energy storage because of their rich active surface and open ion diffusion channels. However, the scalable preparation of carbon materials simultaneously possessing ultrathin 2D feature and hierarchical pores remains a considerable challenge. Herein, a facile one-step method to massively fabricate 2D porous chitin nanosheets (coded as PCNs) via a phytic acid assisted top-down exfoliation of bulk chitin under hydrothermal treatment was presented. Subsequently, 2D carbon nanosheets with extra-thin thickness (3.6 nm), well-defined hierarchical porosity, high specific surface area (855 m2·g-1), as well as abundant self-doped heteroatoms (N, O, P) were fabricated by carbonizing the PCNs, and was named as HPCNs. The as-obtained HPCNs demonstrated remarkable electrochemical performance as electrode material for supercapacitors. The symmetric supercapacitors (SSCs) based on HPCNs exhibited a high specific capacitance of 79 F·g-1 (316 F·g-1 for single electrode) in 6 M KOH aqueous electrolyte solution, as well as a remarkable energy density of 23.8 W·h·kg-1 by using 1 M Li2SO4 as electrolyte. It is also demonstrated that HPCNs/PCNs hybrid dispersions can be used as inks to fabricate conductive films and energy devices with high strength and superior flexibility. This work paves a new avenue for the economical and large-scale synthesis of 2D hierarchically porous carbon materials for energy storage related applications.