Precursors For Carbon Materials Research Articles

High Capacitive Performance of N,O-Codoped Carbon Aerogels Synthesized via a One-Step Chemical Blowing and In Situ Activation Process.

Biomass and its derivatives, with their renewable characteristics, cost-effectiveness, and controllable structural and compositional properties, are promising precursors for carbon materials. Herein, N,O-codoped carbon aerogels were synthesized by carbonization and zinc nitrate activation of histidine. The specific surface area (SSA) was markedly increased with the addition of zinc nitrate, and the maximum value achieved 853 m2 g-1 for ZHC-11 obtained with the molar ratio of 1:1 between histidine and zinc nitrate. The D/G-band intensity ratio increased from 1.55 for the histidine-derived control sample HC to 1.65 for ZHC-11, indicating the enhancement of amorphous feature. The nitrogen content increased from 6.5% for HC to 1.60 for ZHC-11. The optimized microstructure and enriched heteroatom doping are beneficial to the capacitance performance. The optimum electrode exhibited 234.1 F g-1 at 0.1 A g-1 and maintained 116.5 F g-1 at 60 A g-1 in a three-electrode system. In particular, the symmetric supercapacitor showed 121.9 F g-1 and 19.5 Wh kg-1 at 0.2 A g-1. This research offers guidance on the cost-effective synthesis of carbon materials for supercapacitors, while also providing novel insights to realize the complete utilization of biomass derivatives.

Lignin‐Metal Supramolecular Framework Strategy of Self‐Healing Carbon‐Coated CoRu Alloy Nanocatalyst for Efficient Overall Water Splitting

AbstractCommon precursors for carbon materials typically include petroleum‐based polymers or MOF materials. However, these materials often encounter challenges such as metal aggregation, high cost, and metals leaching. In this work, a novel of approach lignin‐metal supramolecular framework complex (MSF@Lignin) is introduced. These complexes are formed through oxidative ammonolysis of lignin (OAL) to synthesize a nitrogen‐doped carbon‐encapsulated CoRu nanocatalyst (CoRu@OALC) via in situ carbonization. CoRu@OALC exhibited exceptional performance in both HER (90 mV) and OER (200 mV) at the current density of 10 mA cm−2, with an overall water splitting voltage of 1.5 V and outstanding stability under high density. During the pyrolysis process, metal became encapsulated by lignin‐derived carbon, occurring within the temperature range of 600–700 °C. In the catalytic process, active sites are primarily located within the defects in lignin‐derived carbon, showcasing a unique “self‐healing” phenomenon within the carbon layer. Oxygen‐containing intermediates (*OH, *O, and *OOH) facilitated the reconstruction of defects on the carbon layer, while the hydrogen‐containing intermediates (*H) contributed to the reappearance of a defect‐rich structure.

Catalytic conversion of carbon dioxide (CO2) using coal-based nano-carbon materials.

Carbon dioxide (CO2) is a prominent greenhouse gas and a widely available carbon resource. The chemical conversion of CO2 into high-value chemicals and fuels is a significant approach for mitigating carbon emissions and attaining carbon neutrality. However, enhancing CO2 adsorption and conversion rates remains a primary challenge in CO2 recycling. The development of high-performance catalysts is pivotal for the catalytic conversion of CO2. In this context, coal-based carbon materials, characterized by their extensive specific surface area and adaptable chemical composition, can offer more reactive active sites and have robust CO2 adsorption capabilities. They can function as either standalone catalysts or as components of composite catalysts, making them promising materials for CO2 reduction. The use of affordable and abundant coal as a precursor for carbon materials represents a crucial avenue for achieving clean and efficient coal utilization. This paper reviews the progress of research on coal-based carbon materials and examines their advantages and challenges as catalysts for CO2 reduction.

Nano-CaCO3 templated porous carbon enable high-rate and ultralong cycle performance supercapacitor

The development of hierarchically porous carbon materials with excellent pore structure via environmentally friendly and low-cost strategies is attractive for high energy density of supercapacitor. Zinc gluconate is an excellent precursor of carbon materials due to its low cost, simple chemical composition, and self-activation during carbonization. In this work, a strategy of activating zinc gluconate with nano‑calcium carbonate as template was proposed to prepare porous carbon (ZnPCCa-1), which has the advantages of high specific surface area of 1328 m2 g−1. The as-prepared ZnPCCa-1 electrode achieved ultra-high rate performance of specific capacitance ∼120 F g−1 at the current density of 20 A g−1, and capacitance retention with 95.1 % even at high current density of 50 A g−1 after 50,000 cycles. The symmetric supercapacitor prepared by ZnPCCa-1 electrode assembly achieves an energy density of 81.1 Wh kg−1 in Et4NBF4 electrolyte, and the capacitance retention keep up to 89.7 % after 10,000 cycles at current density of 20 A g−1. This work demonstrates a promising approach for intelligently regulating hierarchical porous structured carbon, and providing valuable insights for achieving high-performance supercapacitor storage.

Selective synthesis of soft and hard carbons from a single precursor through tailor-made stabilization for anode in sodium-ion batteries

A major factor in classifying carbon materials is their degree of graphitization, which is defined as a structural transition from an amorphous to an ordered crystalline state. Previous studies have shown that graphitization depends on the intrinsic properties of precursors for carbon materials. Thus, these studies on graphitization have been mainly limited to modulating precursors. Herein, we demonstrate the degree of graphitization that can be governed by a stabilization process using polyethylene (PE) as a single precursor, as PE is a non-graphitizable material. PE is stabilized by e-beam irradiation and subsequent thermal oxidation or sulfuric acid treatments to investigate the effects of stabilization methods. The resulting thermally and acid-stabilized PEs are graphitized up to 2,000 °C, and surprisingly, they diverge from a single precursor into soft and hard carbons, respectively. We also confirm that laser desorption/ionization time-of-flight mass spectrometry is a powerful analytical tool for revealing the different structures of thermally and acid-stabilized PEs at the early stage of graphitization based on the formation patterns of carbon cluster ions. In addition, the distinct electrochemical performances of soft and hard carbons are investigated by applying them as anode materials into sodium ion batteries, respectively. We believe that this study provides fundamental insights and practical tools to develop tailor-made carbon materials from a single and common precursor.

Effect of two-stage thermal treatment on the reduction of quinoline-insoluble in Mesophase pitch

ABSTRACT Mesophase pitch (MP) is an important carbon material precursor with excellent physical performance and has a wide application in new energy utilization field. However, the current preparation process leads to a high quinoline-insoluble (QI) content in the MP, limiting its application. Here, we use two-stage thermal treatment to slow the degree of polycondensation during the formation of the MP. The two-stage thermal treatment can facilitate the formation of MP and limit the generation of QI. Moreover, the low content of polycyclic aromatic hydrocarbons (PAHs) in the liquid by-products indicates that the degree of thermal cracking of the feedstock becomes milder. The high content of cycloparaffins in gaseous by-products is due to the better polycondensation of the feedstock. Therefore, a wide area streamlined MP is prepared, which has a high mesophase content (96.8%), a low QI content (20.6%) and a good crystal structure (L c = 57.37 Å, N = 17.64, n = 99.53). At last, a possible mechanism of MP sample formation is discussed, which will provide an insight in the optimization of MP preparation process.

Preparation of Activated Carbon from Korean Anthracite: Simultaneous Control of Ash Reduction and Pore Development

Anthracite stands as a valuable precursor for carbon materials, owing to its high carbon content. However, producing activated carbon from anthracite presents significant challenges due to its elevated ash content (23–40 wt%) and crystalline nature. The high ash content not only fails to contribute to the activation process but also obstructs pore formation on the carbon surface. To address these challenges, this study explores the preparation of activated carbon from anthracite using KOH activation. This method demonstrates remarkable efficacy in enhancing reactivity beyond the inherent physical properties of anthracite. In contrast to physical activation, the utilization of KOH as a chemical agent substantially enhances the specific surface area, resulting in a production yield of 62% and a specific surface area that reaches up to 1596 m2/g at a KOH/anthracite weight ratio of 4.0. Moreover, rinsing the activated sample with tap water achieves an ash removal rate of about 37.9%, surpassing twice the rate achieved through acid pretreatment (67.0%). A noteworthy observation from this study is the substantial reduction in the content of major ash components, such as silicon (Si) and aluminum (Al), both of which are prominent constituents in anthracite ash. Following KOH activation, their levels decrease by approximately 54% to 65%, respectively. These findings highlight the potential of utilizing available anthracite, even with elevated ash content, as a superior carbon material. Fundamentally, the KOH activation method serves a dual purpose: it effectively reduces ash content and promotes pore creation within a highly alkaline environment. This dual advantage positions the method as a promising approach for the production of top-tier activated carbon.

Lignin-derived heteroatom-doped hierarchically porous carbon for high-performance supercapacitors: “Structure-function” relationships between lignin heterogeneity and carbon materials

Sustainably sourced lignin is a desired precursor for carbon materials due to its cross-clinked aromatic structure and high carbon content. However, the heterogeneity of lignin feedstock presents non-negligible effects on its physicochemical properties and thereby substantially influences its applications in carbon materials fabrication. In this work, fractionation of corn stalk enzymatic hydrolysis lignin via a simple two-step ordinal dissolution was adapted to reduce lignin heterogeneity and further improve the microstructure and electrochemical performances of lignin-derived heteroatom-doped carbon materials. The results revealed that the fractionation process successfully obtained three lignin fractions with sequentially increasing molecular weight and specific surface area. When the three lignin fractions were subjected to carbonization/activation to fabricate N/P/S co-doped carbon, the F3-derived carbon material (LC-F3) showed the highest specific surface area (2022.4 m2/g) and the best heteroatom doping effect due to the improved activation process resulted from the largest specific surface area of F3. Moreover, the good thermal stability of F3 also contributed to the maintenance of disordered structure during carbonization. Therefore, LC-F3 exhibited excellent specific capacitance (337.2 F/g, 0.5 A/g) and cycling stability (96.5% after 10,000 cycles) as a consequence of its high disordered level, heteroatom doping density and specific surface area. Consequently, this work systematically evaluates the effects of lignin fractionation on the physicochemical structural and electrochemical performances of the carbon materials and further proposes a simple strategy to enhance electrochemical properties of the heteroatom-doped carbon materials through lignin fractionation.

CO2 capture by microporous carbon based on Brazil nut shells.

The increase in burning, deforestation, and the exorbitant use of fossil fuels have contributed to the increase in carbon dioxide emissions; this gas is responsible for the intensification of the greenhouse effect and radical climate changes. In this way, it becomes necessary to find alternatives to reduce its emission. Porous carbon materials synthesized from lignocellulosic waste can be employed in technologies for capture and utilization of CO2 due to the advantages such as selectivity, low-cost synthesis, high surface area and pore volume, and thermal and chemical stability. Considering the availability of Brazil nut biomass residues in the Amazon region, this article proposes to synthesize activated carbon from the lignocellulosic residue using physical and chemical activation methods for CO2 capture. The analysis of N2 adsorption-desorption isotherms proves the predominance of a microporous structure when using the two synthesis methods described here. In physical activation, the surface area was 912 m2/g, while, in chemical activation, it was 1421 to 2730 m2/g. The sample treated via the chemical method (BS6-K1) showed better performance in CO2 adsorption, with adsorption results of 3.8 and 6mmol/g of CO2 at 25 ℃ and 0°C, respectively, at 101kPa. CO2 adsorption capacity is due to the high volume of ultramicropores. It is believed that the microporous carbon material synthesized from Brazil nut residues is an alternative precursor for carbon materials used as CO2 capture.

Construction of self-supporting ultra-micropores lignin-based carbon nanofibers with high areal desalination capacity

Lignin is a renewable biomacromolecule that can be used as precursors for carbon materials. In this work, highly flexible lignin-based carbon nanofibers with abundant ultra-micropores are constructed via electrospinning, oxidative stabilization and carbonization. The results indicate that replacing PAN with 80 % lignin is feasible in regulating ultra-micropores. The synthesized L4P1-CNFs possess many attractive properties (e.g., pore size distribution, electrochemical and deionization property) compared with that produced from other non-renewable precursors or more-complexed processes. It shows excellent electrochemical double-layer capacitance in 6 M KOH (233 to 162 F g−1 at 0.5 to 5 A g−1) and 1 M NaCl (158 to 82 F g−1 at 0.5 to 5 A g−1) electrolytes. Upon assembling into CDI cells, the average salt adsorption rate could reach 1.79 mg g−1 min−1 at 1.2 V and 3.32 mg g−1 min−1 at 2 V in 500 mg L−1. Benefiting from the excellent flexibility, we innovatively stack four layers of L4P1-CNFs to improve the areal electrosorption capacity to 0.0817 mg cm−2 at 500 mg L−1, significantly higher than that of traditional carbon-based electrodes. The good desalination property makes lignin-based carbon nanofibers ideal for practical, low-cost capacitive deionization applications.

Waste-Glycerol as a Precursor for Carbon Materials: An Overview

Biodiesel is produced by the transesterification of animal fats and vegetable oils, producing a large amount of glycerol as a by-product. The crude glycerol cannot be used in the food or pharmaceutical industries. It is crucial to transform glycerol into value-added products with applications in different areas to biodiesel be economically viable. One of the possible applications is its use as a precursor for the synthesis of carbon materials. The glycerol-based carbon materials have distinct properties due to the presence of sulfonic acid groups on the material surface, making them efficient catalysts. Additionally, the glycerol-based activated carbon materials show promising results concerning the adsorption of gases and liquid pollutants and recently as capacitors. Despite their potential, currently, little research has been carried out on the synthesis and application of those materials. This review summarized the preparation and application of carbon materials from glycerol, intending to show the potential of these materials.

One-step preparation of lignin-based solid acid by carbonization and sulfonation to catalyze the synthesis of dimethyl adipate

Lignin is a high-quality precursor of carbon materials, rich in content and low in price. Sodium lignosulfonate was used as a raw material to prepare a high-efficiency catalyst for the esterification of adipic acid and methanol to synthesize dimethyl adipate by a one-step carbonization sulfonation process. The catalyst synthesized by this method has high sulfonic acid groups, and the catalytic process does not need to use sulfuric acid and other advantages. Through characterization analysis, study the relationship between the structure of the catalyst and the catalytic performance. A preliminary study on the industrial application of the catalyst has been done. The optimal reaction conditions were reached when the catalyst dosage is 20% of the mass of adipic acid, the alkyd ratio is 8:1, the stirring speed is 600r/min, the reaction temperature is 346 K, and the reaction time is 120 min

Facile synthesis and electrochemical properties of alicyclic polyimides based carbon microflowers for electrode materials of supercapacitors

Polyimide(PI) as the precursor of carbon materials for electrodes of supercapacitor has attracted extensive attention. Herein, a kind of porous carbon materials derived from alicyclic polyimides were fabricated by the solvothermal approach to form PI microflowers, followed by further pyrolysis. Due to the thermal instability of alicyclic structures derived from cyclobutane-1,2,3,4-tetracarboxylic dianhydride(CBDA), the carbon microflowers showed rich micro/mesoporous structures and large specific surface areas. The structures and electrochemical performance of the carbon microflowers were studied by adjusting precursor solution concentrations and final carbonizing temperatures. When the precursor concentration was 45 mg mL−1 and carbonization temperature was 800 °C, PIDMAc-45-800 performed the best electrochemical behaviors with the specific capacitance of 239.6 F g−1 at the current density of 0.5 A g−1. As the current density increased to 10 A g−1, the retention rate of specific capacitance reached 80.9%. After assembled a symmetric electrode, it exhibited high cycling stability with a negligible 0.1% capacitance reduction after 10,000 cycles at a current density of 1 A g−1. Moreover, after being placed for one year, the electrochemical performance of the cells decreased slightly, indicating good stability and reliability. Thus, the work offers a facile method to construct the N and O-doped and porous carbon microflower materials by virtue of the alicyclic PI as precursors, which will play an important role in the field of energy storage and conversion.

Preparation of activated carbon from alkali lignin using novel one-step process for high electrochemical performance application

As the second most abundant bio-resource and as a byproduct of lignocellulose material processing, alkali lignin has to become a quantitative issue due to its difficulties to handle. On the other hand, lignin has high natural carbon contents, so it has the potential to act as a precursor for carbon materials. However, many previous researchers do three steps to transform it into high porous carbon: precipitation by reducing the alkaline compound, calcination to transform it into carbon, and carbon activation by adding alkaline compound again. In this study, the porous carbon material from alkali lignin in a one-step process for use as an electrode in supercapacitor and electrocatalyst is examined. The evaporation and especially carbonation temperature are studied to obtain the high porous carbon. After varying calcination temperatures, the carbon material's characterization was investigated to examine porosity, morphology, crystallinity, specific electrocapacity, and Oxygen Reduction Reaction (ORR) electrocatalyst activity. The carbon derived from Na-lignin via calcination at 700 °C had the highest electrocapacity of 168.29F/g. The electron transformed number is 2.23, indicating that the carbon derived from Na-lignin via calcination is promising for an electrode agent of supercapacitor and electrocatalyst for ORR.

Nitrogen-enriched micro-mesoporous carbon derived from polymers organic frameworks for high-performance capacitive deionization

Nitrogenization is an effective method for improving the capacitive deionization (CDI) performance of porous carbon materials. In particular, polymer organic frameworks with heteroatom doping, containing an ordered pore structure and excellent electrochemical stability, are ideal precursors for carbon materials for high-performance CDI. In this study, a nitrogen-enriched micro-mesoporous carbon (NMC) electrode was fabricated by carbonizing a Schiff base network-1 at 500, 600, and 700 °C. Scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, N2 adsorption-desorption, the contact angle of water, cyclic voltammetry, and electrochemical impedance spectroscopy were used to characterize the morphological structure, wettability, Brunauer–Emmett–Teller surface areas, and electrochemical performance of the NMCs. The results showed that the NMC carbonized at 600°C achieved the best specific capacitance (152.33 F/g), as well as a high electrosorption capacity (25.53 mg/g) because of its chemical composition (15.57% N) and surface area (312 m2/g). These findings prove that NMC is viable as an electrode material for desalination by high-performance CDI applications.

Sustainable Carbon Materials toward Emerging Applications.

It is desirable for a sustainable society that the production and utilization of renewable materials are net-zero in terms of carbon emissions. Carbon materials with emerging applications in CO2 utilization, renewable energy storage and conversion, and biomedicine have attracted much attention both academically and industrially. However, the preparation process of some new carbon materials suffers from energy consumption and environmental pollution issues. Therefore, the development of low-cost, scalable, industrially and economically attractive, sustainable carbon material preparation methods are required. In this regard, the use of biomass and its derivatives as a precursor of carbon materials is a major feature of sustainability. Recent advances in the synthetic strategy of sustainable carbon materials and their emerging applications are summarized in this short review. Emphasis is made on the discussion of the original intentions and various sustainable strategies for producing sustainable carbon materials. This review provides basic insights and significant guidelines for the further design of sustainable carbon materials and their emerging applications in catalysis and the biomedical field.

Multifunctional lignin-based nanocomposites and nanohybrids.

Significant progress in lignins valorization and development of high-performance sustainable materials have been achieved in recent years. Reports related to lignin utilization indicate excellent prospects considering green chemistry, chemical engineering, energy, materials and polymer science, physical chemistry, biochemistry, among others. To fully realize such potential, one of the most promising routes involves lignin uses in nanocomposites and nanohybrid assemblies, where synergistic interactions are highly beneficial. This review first discusses the interfacial assembly of lignins with polysaccharides, proteins and other biopolymers, for instance, in the synthesis of nanocomposites. To give a wide perspective, we consider the subject of hybridization with metal and metal oxide nanoparticles, as well as uses as precursor of carbon materials and the assembly with other biobased nanoparticles, for instance to form nanohybrids. We provide cues to understand the fundamental aspects related to lignins, their self-assembly and supramolecular organization, all of which are critical in nanocomposites and nanohybrids. We highlight the possibilities of lignin in the fields of flame retardancy, food packaging, plant protection, electroactive materials, energy storage and health sciences. The most recent outcomes are evaluated given the importance of lignin extraction, within established and emerging biorefineries. We consider the benefit of lignin compared to synthetic counterparts. Bridging the gap between fundamental and application-driven research, this account offers critical insights as far as the potential of lignin as one of the frontrunners in the uptake of bioeconomy concepts and its application in value-added products.

Synthesis and characterization of poly (acrylonitrile-g-lignin) by semi-batch solution polymerization and evaluation of their potential application as carbon materials

Understanding the factors that govern the graft polymer structure is of central importance to the development of technologies for converting polymers into carbon materials. In this work, poly (acrylonitrile-g-lignin) was synthesized by one-pot semi-batch solution polymerization of acrylonitrile (AN) with different amounts of Kraft lignin (KL), aiming the carbon materials producing. The synthesis process parameters to obtain poly (acrylonitrile-g-lignin) hybrid polymers from different KL contents were optimized. The purpose of this work was to substitute part of the AN by KL, with the KL amount varying from 0 to 35 wt.% in the copolymer and to investigate the consequent effects on the grafting percent, viscosity, overall monomer conversion, molar masses, thermal properties and carbon yield. The results obtained show the success in preparation of the grafted polymers with KL and that this insertion improved the thermal stability of the polymers and the carbon yield. The molar masses of poly (AN-g-KL) showed direct relationship with the amount of KL used and the grafting percentage. The results showed that the grafting percentage and viscosity of solutions decreases as the concentration of KL increased. The molar mass results and thermal properties showed a direct relationship to the KL concentration in the synthesized copolymer. Among the proportions of AN/KL studied, the copolymer 75/25 (P-25KL) presented the most promising results for application as carbon material precursor.

Glyoxalation of Kraft lignin and optimization of electrospinning process parameters for producing polyacrylonitrile/KL nanomats for potential applications as carbon material

In this work, Kraft lignin (KL), glyoxalated KL and its blends with polyacrylonitrile (PAN/KL) were electrospun by solution electrospinning in order to investigate the morphology of the mats to be used in carbon material applications. The process parameters to obtain PAN/KL nanofibers with higher amount of KL and without defects were optimized. Three types of KL were used in this work: non-purified (KL), purified (KLp) and glyoxalated (KLg). The effects of the glyoxalation reaction time and the ratio of glyoxal-to-KL were, also, investigated in order to improve the molar mass of the KL. The results show that the molar mass of each glyoxalated KL increases compared to that of the standard KL. The molar mass remained unchanged with increasing the reaction time and ratio of glyoxal-to-KL. All obtained nanofiber mats were characterized by scanning electron microscopy (SEM) and their morphology showed to be dependent on the ratio of the PAN/KL used. Increasing the KL content decreases the diameter of the nanofibers. The maximum KL content in the PAN/KL blend, required to produce nanofibers without defects and with small fiber diameter, was 50 wt.%, making this material promising for a carbon material precursor. For the case of KLg, nanomats with beads were obtained with 70 and 80 wt.% KLg in the blend. Thermal properties of the nanomats showed a direct relationship to the content of KL used and its molar mass. In addition, these results point to a new approach for the application of KL and PAN/KL nanofibers.

Cellulose-Derived Carbon Microfiber Mesh for Binder-Free Lithium-Sulfur Batteries.

The practical application of lithium-sulfur batteries (LSBs) has been impeded by several chronic problems related to the insulating nature of sulfur and lithium sulfide, in addition to the dissolution and diffusion of lithium polysulfides. In view of these problems, a large variety of carbonaceous materials have been employed to enhance the electronic conductivity of the cathode and/or sequester lithium polysulfides within conductive matrixes. Although they may exhibit impressive electrochemical performance, the fabrication of most carbon materials involves costly precursors and complicated procedures. Waste paper-the main constituent of municipal waste-is composed of carbohydrates, and can be an ideal precursor for carbon materials. Herein, carbon microfiber meshes (CMFMs) obtained by the pyrolysis of common filter paper in argon (A-CMFM) or ammonia (N-CMFM) were used to form sulfur cathodes. Compared with LSBs based on A-CMFM, those based on N-CMFM demonstrated higher specific capacity and better rate capability, with a capacity of 650 mA h g-1 at 0.2 C and 550 mA h g-1 at 0.5 C. This was owing to the strong immobilization of lithium polysulfides resulting from the heteroatom doping and hydrophilicity of N-CMFM. The results indicate that cellulose paper-derived carbon is a promising candidate for application in high-performance LSBs.