Nitrogen-rich Porous Carbon Research Articles

Buckwheat derived nitrogen-rich porous carbon material with a high-performance Na-storage

Nitrogen-rich porous carbon materials have been prepared by pyrolyzing buckwheat with a nano-CaCO3 template. The buckwheat-derived porous carbons exhibit high nitrogen content (3.14%) and interconnected mesoporous dominated porous structures with some macropores, which endows them high efficient electrochemical energy storage. When they tested as anode materials for sodium ion batteries, an initial reversible capacity of 258 mAh g−1 is obtained at 30 mA g−1, and a high capacity of 185 mAh g−1 can be maintained after 100 cycles. Moreover, this work suggests that the cost-effective biomass material of buckwheat is of great potential to be used as anodes for sodium ion batteries.

Three‐dimensional nitrogen rich bubbled porous carbon sponge for supercapacitor & pressure sensing applications

Three-dimensional (3D) porous carbonaceous materials offer numerous merits such as light-weight, high surface area, flexibility, and thus hold immense potential in energy storage applications. In this work, we report preparation of nitrogen-rich free-standing compressible porous neuron-like carbon sponge using commercially available kitchen sponge by a facile, cost-effective, and scalable synthetic strategy. The unique neuron-like bubbled interconnected carbon structure with enhanced N/O functionalities improves the electrochemical performance by providing sufficient space for ion transport and large accessible surface-active sites. This material also delivers high current response under compressive stress acting as a pressure sensor. This bubbled carbon material achieves an improved specific capacitance of 268.5 F g−1 at 0.5 A g−1. As a self-supporting electrode in a symmetrical supercapacitor cell, it still delivers a good specific capacitance of 167 F g−1 at 0.35 A g−1, retaining 92.5% of capacitance over 7000 charge/discharge cycles. Furthermore, the device delivers a maximum energy density of 14.8 Wh Kg−1, demonstrating its immense potential for multi-functional applications owing to its unique features.

Nitrogen-rich porous carbon in ultra-high yield derived from activation of biomass waste by a novel eutectic salt for high performance Li-ion capacitors

High performance N-doping porous carbon (NDPC) are ideal electrode materials for Li-ion capacitors (LICs). However, the practical application of NDPC is extremely limited, which is mainly attributed to the typical methods for the scale preparation NDPC are time-consuming, high cost and low yield. Herein, we have developed a new route for high efficient, environment friendly, low cost and high yield fabrication of NDPC, using biomass waste as the carbon source and a novel eutectic salt as the activation agent. After a series of comparative experiments, the application of eutectic salt herein not only reduce the process time and cost, but also obviously enhance the yield, the specific surface area (SSA) and nitrogen-doping content of NDPC sample (labelled as NDPC-0.5). In combination of the rich N-doping level, larger SSA and interconnected porous structure, the NDPC-0.5 sample exhibit an excellent electrochemical performance as both cathode and anode materials for a LIC, with specific discharge capacities of ∼60 and 290 mAh g−1 at a current density of 5 A g−1. The resultant NDPC-0.5//NDPC-0.5 LIC device delivers a high energy density of 116.9 Wh kg−1 at 500 W kg−1, with a capacity retention of 81% after 8000 cycles at 2 A g−1.

Influence of annealing temperature in nitrogen doped porous carbon balls derived from hypercross-linked polymer of anthracene for supercapacitor applications

Nitrogen rich porous carbon balls are derived from hypercross-linked polymers (HCPs) of anthracene and subsequent carbonization with urea. The obtained materials exhibit combination of abundant microporous and minimal mesoporous property with large surface area (623.27 to 928.44 m2 g − 1). The influence of annealing temperature in nitrogen doped porous HCPs was examined the capacitive performance of the prepared electrode materials using electrochemical techniques. A symmetric device was assembled, and it shows a high specific capacitance of 206.4 F g − 1 at 0.2 A g − 1 with excellent rate capability. Also, the material exhibits excellent durability only 3.5% loss was observed after 5000 cycles (capacitance retention of 96.5%). These outcomes justify that nitrogen anchored porous carbon balls are excellent materials for high-performance symmetric supercapacitors.

Iron single-atom catalyst anchored on nitrogen-rich MOF-derived carbon nanocage to accelerate polysulfide redox conversion for lithium sulfur batteries

Permanent adsorption-conversion of lithium polysulfides by iron single atom anchored porous nitrogen-rich carbon nanocages endows lithium sulfur batteries with long lasting rate performance.

Nitrogen-rich porous carbon modified electrochemical sensor for the detection of acetaminophen

A simple and sensitive sensor based on a glassy carbon electrode modified with nitrogen-rich porous carbon (P-NC) has been developed for the detection of acetaminophen (APAP). The nanocomposite P-NC was prepared by the assisted carbonization of the zeolitic imidazolate framework ZIF-8 using poly(vinylpyrrolidone), and its morphology and surface structure were thoroughly characterized. The results revealed that the P-NC prepared has a uniform pore size distribution with a high superficial area. The electrochemical properties of P–NC–modified electrodes were investigated by cyclic voltammetry, electrochemical impedance spectroscopy, and differential pulse voltammetry. It was found that the modified electrode has a high catalytic activity for APAP and exhibits good linearity for the 3–110 μM concentration range with a minimum detection limit of 0.5 μM (S/N = 3). In addition, the constructed sensor exhibits good repeatability, stability, recovery, and selectivity, allowing it to be successfully applied to the detection of APAP in real-world human urine samples.

Commercial-Level Energy Storage via Free-Standing Stacking Electrodes

Summary Pseudocapacitors with a fast faradic redox reaction during the electrochemical charge/discharge process hold great promise for delivering high power and high energy. Here, we used emerging oxygenated carbon nitride (OCN) as a model for nitrogen- and oxygen-enriched carbons and found an anion-selective charging behavior in aqueous electrolytes. The N- and O-mediated hydroxyl anion-selective charging originates from inbuilt surface-positive electrostatic potential localized at heptazine and quaternary N atom structural units. The carbon atoms in heptazine adjacent to pyridinic N act as the electron transfer active sites for faradic pseudocapacitance. The OCN free-standing films (FSFs) were developed as current collector-free electrodes, and stacking OCN FSFs can confer a cell with loading weight over a commercial level. For demonstration, a symmetrical cell with 17.7 mg cm−2 delivers an energy of 140.9 mW h at a high power of 2,499.9 mW, and almost 100% capacitance retention after 20,000 charge/discharge cycles at 50 mA.

Ultraporous nitrogen-rich carbon nanosheets derived from the synergy of eutectic liquid and zeolitic imidazolate for energy applications

Reported here is a unique and novel synthetic method for the preparation of highly porous nitrogen-rich carbon nanosheets from ZIF-8 (ZIF, zeolitic imidazolate framework) with the assistance of eutectic liquid. Due to the low melting temperature, a mixture of eutectic salts can provide a special atmosphere for the carbonization process and function as the template to support the ZIF-8 framework. The formation of the ultraporous nanosheets can be ascribed to the excellent miscibility between the eutectic salts and ZIF-8 framework, thus helping convert the ordered calcined intermediate species into extended carbon sheets at high temperature while inheriting the microporous structure from the prototypical ZIF-8. By controlling the ratio of eutectic liquid to ZIF-8 framework, the BET surface area of carbon nanosheets can be systematically tuned, with the highest BET surface area up to 2960 m2 g−1. In addition to this impressive high surface area, the pore size distribution follows well with the pristine ZIF-8. The nitrogen content varies from 9.9 wt % to 13.4 wt %. These characteristics contribute to the excellent performance of CO2 adsorption (5.45 mmol g−1 at 1atm and 273K) and oxygen reduction reaction (ORR) catalysis due to the large numbers of accessible active sites.

High-Performance Electrodes for a Hybrid Supercapacitor Derived from a Metal–Organic Framework/Graphene Composite

Metal–organic frameworks (MOFs) hold great potential in the development of electrode materials for next-generation supercapacitors because of their versatile porous architectures. Here we report our finding in synthesis and characterization of electrode materials derived from a pillared MOF, Ni2(ADC)2(DABCO) for a high-performance hybrid supercapacitor, where ADC represents 9,10-anthracenedicarboxylate and DABCO corresponds to 1,4-diazabicyclo[2.2.2]octane. The positive electrode is derived from a single MOF and graphene oxide (GO) composite, consisting of a highly functionalized nickel hydroxide coupled with graphene, ADC, and DABCO groups. A hierarchically porous nitrogen-rich carbon, derived from the same MOF/GO composite, is used as the negative electrode. The resulting hybrid supercapacitor demonstrates high energy and power density (59 and 48 Wh kg–1 at 0.9 and 15.5 kW kg–1, respectively), good rate capability (19% capacity loss from 1 to 20 A g–1), and exceptional cycling stability (95% capacity retention over 10000 cycles at 20 A g–1). These findings imply that the combination of pillared MOFs and rGO significantly enhances the electrochemical performance of the resulting electrode materials. In addition, this study also provides a new material preparation strategy (MOFs-rGO-derived materials) for synthesis of high-performance electrode materials for other energy storage devices.

The use of natural hierarchical porous carbon from Artemia cyst shells alleviates power decay in activated carbon air-cathode

Activated carbon (AC) air-cathode is demonstrated to be promising for the energy recovery from wastewaters. However, it suffers from the performance decay after long-term operation in microbial fuel cells (MFCs). Here we add a natural hierarchical porous nitrogen-rich carbon material, carbonized Artemia cyst shells (LC), to alleviate the power decay. When the air-cathode is made of a mixture of AC and LC with a mass ratio of 1:2 (named 1AC2LC), the current densities are 28% (the beginning) and 65% (after 1 year's operation) higher than AC cathodes, and the long-term power densities increase from 0.871 ± 0.002 (AC) to 1.296 ± 0.005 W m−2 (1AC2LC) after one year's operation. The Coulombic efficiency increases by 20% than the control. This can be primarily attributed to these inerratic hierarchical pores enhancing oxygen transfer in the catalyst layer since the oxygen mass transfer coefficient is increased by 3.4 times, where the meso- and macro-pores are enlarged, showing the importance of oxygen transfer on the longevity and energy production. Our results show a novel way, addition of inexpensive carbonized Artemia cyst shells, to optimize cathodic porous structure and enhance the longevity of MFCs.

Superior Lithium/Potassium Storage Capability of Nitrogen-Rich Porous Carbon Nanosheets Derived from Petroleum Coke

Tremendous attention has been paid to carbon-based anodes for lithium-ion and potassium-ion batteries. Nevertheless, conferring high energy storage properties using carbon-based anodes is still challenging. In this work, petroleum coke-based nitrogen-doped porous carbon nanosheets (N-PCSs) were prepared using carbon nitride (g-C3N4) as both a template and nitrogen source and tested as advanced anode materials. The as-obtained N-PCSs constructed through an in situ solid-state approach take advantage of both the high capacity and excellent cycling stability. High capacities were obtained for Li-ion and K-ion batteries (407 mAh g-1 after 500 cycles at 3720 mA g-1 and 206 mAh g-1 after 300 cycles at 1000 mA g-1, respectively); these are some of the best capacities for carbon-based electrode materials and could be ascribed to the unique microstructure of the anodes, i.e., nanosheet morphology, developed porosity, ultrahigh nitrogen doping, and high level of disorder. Meanwhile, this study provides a milestone for high-valued utilization of petroleum coke and other kinds of heavy oil.

Direct transformation of bulk copper into copper single sites via emitting and trapping of atoms

Single-atom catalysts exhibit intriguing properties and receive widespread interest for their effectiveness in promoting a variety of catalytic reactions, making them highly desired motifs in materials science. However, common approaches to the synthesis of these materials often require tedious procedures and lack appropriate interactions between the metal atoms and supports. Here, we report a simple and practical strategy to access the large-scale synthesis of single-atom catalysts via direct atoms emitting from bulk metals, and the subsequent trapping on nitrogen-rich porous carbon with the assistance of ammonia. First, the ammonia coordinates with the copper atoms to form volatile Cu(NH3)x species based on the strong Lewis acid–base interaction. Then, following transportation under an ammonia atmosphere, the Cu(NH3)x species are trapped by the defects on the nitrogen-rich carbon support, forming the isolated copper sites. This strategy is readily scalable and has been confirmed as feasible for producing functional single-atom catalysts at industrial levels. Single-atom catalysts have proven successful in many catalytic applications. Now, Li, Wu and co-workers show that single-atom catalysts can be prepared directly from bulk metals using an ammonia atmosphere, owing to the formation of volatile metal–ammonia species that are trapped by the nitrogen-rich carbon support.

Carbon Thin-Layer-Protected Active Sites for ZIF-8-Derived Nitrogen-Enriched Carbon Frameworks/Expanded Graphite as Metal-Free Catalysts for Oxygen Reduction in Acidic Media

Generally, sluggish oxygen reduction reaction (ORR) kinetics on cathode limits the practical application of the direct methanol fuel cell (DMFC). In this study, zeolitic-imidazolate-framework-8 (ZIF-8)-derived carbon is used to decorate expanded graphite (EG) to prepare a nitrogen-rich porous metal-free carbon framework (Z8-NCF-P/EGs) as catalyst for ORR in DMFC. Through use of a simple one-pot method, ZIF-8 is firmly anchored on EG to obtain the ZIF-8/EG precursor via a polyvinypyrrolidone (PVP)-assisted route. After carbonization and acid etching, the formed micromesoporous structure contributes to the high specific surface area and well-distributed porous 3D bulk networks of Z8-NCF-P/EGs, which provide short diffusion paths for rapid oxygen and mass transfer kinetics. Z8-NCF-P/EG-10 (ZIF-8/EG weight ratio of 10) exhibits activity comparable to that of commercial Pt/C (10 wt %) and methanol tolerance and stability much higher than those of Pt/C in acidic electrolyte. EG contributes to the uniform distri...

Schiff-Base/Resin Copolymer under Hypersaline Condition to High-Level N-Doped Porous Carbon Nanosheets for Supercapacitors

We develop a novel strategy to fabricate nitrogen-rich porous carbon nanosheets (N-PCNs) using Schiff-base/resin copolymer under hypersaline medium. Melamine-terephthalaldehyde Schiff-base containning high-bond-energy C=N covalent bonds effectively reduces the loss of the N species during carbonization and thus provides high nitrogen dopants, while the introduction of melamine-formaldehyde resin and ZnCl2 as a solubility enhancing stabilizer plays a key synergistic effect in making the formation of stable polymeric network. Besides, ZnCl2 also serves as a salt-templating and a foaming agent. The resultant N-PCNs have a rich N-doping of 6.55 wt %, a unique nanosheet morphology with a thickness of ∼200 nm, and a large surface area of 1403 m2 g–1 along with rational porous architecture, which affords superior electrochemical performances for a supercapacitor electrode such as high gravimetric capacitances of 362 and 268 F g–1 at 2.0 A g–1 in a three-electrode and a two-electrode system, respectively, using K...

Sulfur-infiltrated yeast-derived nitrogen-rich porous carbon microspheres @ reduced graphene cathode for high-performance lithium-sulfur batteries

The defects of polysulfide dissolution and sulfur insulating causes in Li-sulfur batteries have effectively diminished by immobilizing sulfur in porous carbon microspheres via the interactions of doping-nitrogen and encapsulating-reduced graphene. The nitrogen-rich porous carbon microspheres were prepared by using yeast as natural precursor and high content of nitrogen (up to 8.52%) doped carbon microspheres was confirmed by the elemental analysis. As cathode for lithium-sulfur batteries, the rGO@HYC/S composite exhibits a high retention capacity of 921 mA h g−1 at 0.2 C and 675 mA h g−1 at 1 C over 200 cycles. The battery delivers low capacity decay rate of 0.09% and stable coulombic efficiency about 98% at 1 C during the 200 cycles. Further, we reveal that the enhanced electrochemical performance is ascribed to a hollow porous structure of carbon framework for sulfur storage, carbon matrix exerted by nitrogen-doping for polysulfide adsorption, rGO wrapper for polysulfide interception and conductivity improvement.

Nitrogen-rich Porous Carbon Derived from Biomass as High Performance Electrode Materials for Supercapacitors

Nitrogen-rich Porous Carbon Derived from Biomass as High Performance Electrode Materials for Supercapacitors

One-step synthesis of chitin-derived nitrogen-rich porous carbon fiber assisted with ammonium chloride chemical blowing for supercapacitors

Rich nitrogen-doped porous carbon fiber (NC–NH4Cl) was successfully prepared from chitin via environmentally friendly simple pyrolysis supplemented with ammonium chloride as a recyclable porogen and nitrogen source. Compared with NH4HCO3 and (NH4)2SO4, NH4Cl proved to be the most effective porogen and nitrogen dopant for chitin. The as-made NC–NH4Cl exhibited a 3D architecture formed by numerous intertwined microfibrils with a hierarchical micro/mesoporous structure. Moreover, NC–NH4Cl possessed a high nitrogen content of 10.0 at.%, and about 70% of the nitrogen was in the form of pyridinic-N and pyrrolic-N. The NC–NH4Cl electrode could deliver superior specific capacitance of 284 F g−1 at a current density of 0.5 A g−1, as well as favorable rate performance (ca. 66.3% retention as the current density rose from 0.5 to 20 A g−1) and long cycle life (ca. 96.9% maintained after 5000 cycles) in a three-electrode configuration. The assembled NC–NH4Cl-based symmetric capacitor presented a desirable energy density of 16.67 Wh kg−1 at 1 A g−1. The results suggest that NC–NH4Cl is a promising candidate for supercapacitors.

Biomass based iron and nitrogen co-doped 3D porous carbon as an efficient oxygen reduction catalyst

An iron and nitrogen co-doped 3D porous carbon catalyst with high performance for oxygen reduction reaction (ORR) is produced by pyrolysis. The precursor is a mixture of red date, ferrous (Ⅱ) acetate, and graphitic carbon nitride (g-C3N4). g-C3N4 is the nitrogen source and also the sacrificial template, which plays a key role in the formation of a porous nitrogen rich carbon structure with high surface area. It is found that active sites and catalytic performance of synthetic materials are significantly influenced by the Fe content. In comparison with commercial Pt/C catalyst, the synthetic Fe-N-C with optimized composition exhibits comparable ORR activity and superior methanol tolerance. This work provides a feasible approach to develop cost-effective and highly efficient non-precious metal electrochemical catalysts for oxygen reduction.

Hollow Nitrogen Rich Carbon Nanowire Array Electrode for Application in Lithium-Ion Battery

The anodic aluminum oxide template was prepared and used to fabricate polyacrylonitrile (PAN) nanowire arrays by mechanical hydraulic method, which provides a new idea for the preparation of polymer nanowires. By further carbonize the PAN nanowires at elevated temperatures, the porous nitrogen-rich carbon nanowires could be directly obtained and used as lithium-ion batteries anode material. The nitrogen-rich carbon nanowire based anode exhibited high initial capacities and maintained an outstanding reversible lithium storage capacity of 317.12 mAh g-1 after 50 cycles at a current density of 30 mA g-1, combined with an excellent rate capability of 317.17, 296.70, 265.02, 234.71, 177.02 mAh g-1 under the current density of 30, 50, 100, 200, 500 mA g-1 respectively. Further, this nitrogen-rich carbon nanowire material also has unique advantages in catalysis, supercapacitors and hydrogen storage application potential due to the porous carbon nanowire structure and the large amount of nitrogen doping.

Carbon nitride template-directed fabrication of nitrogen-rich porous graphene-like carbon for high performance supercapacitors

Facile yet rationally designed strategy for advanced electrode material synthesis is pivotal for energy storage. Herein, we report an protocol for g-C3N4 template-directed in-situ fabricating nitrogen-rich porous graphene-like carbon sheets (NPGCs) by using plasma-enhanced chemical vapor deposition followed with high-temperature pyrolysis process, which totally avoids the postsynthetic template-removal. The resultant NPGCs integrate a range of intriguing features including highly conductive interconnected structure (693 S m−1), abundant mesoporous with ultrahigh pore volume (4.35 cm3 g−1), large specific surface area (1277 m2 g−1), high N doping (8.75 wt%), and good wettability. As supercapacitor electrode, the NPGCs exhibit a quite encouraging specific capacitance of 261 F g−1 at 1 A g−1, excellent rate capability (189 F g−1 even at 100 A g−1), and outstanding cycle performance (97% capacitance retention at 10 A g−1 after 20000 cycles), which outperforms most carbon-based materials reported to date. Moreover, the assembled supercapacitors deliver a high power density of 28.4 kW kg−1 with a energy density of 6.53 Wh kg−1 at 100 A g−1. Our work is expected to open up new avenues for developing efficient nitrogen-doped porous carbon materials in a facile and viable way.