Nanoporous Carbon Materials Research Articles

Nanoporous Carbon from Durian Peel via Hydrothermal-Carbonization and their Application in Ripening Delay of Durian

This research was aimed to examine conditions on synthesis of nanoporous carbon materials from durian peel via the process of hydrothermal carbonization (HTC) as an application for delaying durian ripening process. The experiment was conducted by using durian peel as materials for producing nanoporous carbon via the process of hydrothermal at 160-200 °C for 8-24 hours. It also included the process of carbonization at 500-900 °C for 2 hours under nitrogen atmosphere for developing pore structure and removing contaminants to obtain the nanoporous carbon. The properties of nanoporous carbon were characterized by scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FT-IR) and Raman spectrometer analysis. The results indicated that the process of hydrothermal at 200 °C for 12 hours and carbonization at 900 °C for 2 hours was suitable for delaying ripe durian. This is become of the carbon content, porous structure and amorphous structure increased with HTC temperature.

Modeling of Forming a Nanoporous Structure of Carbon Materials for Electrodes of Electrochemical Capacitors

The paper presents the results of predicting the physical properties of nanoporous carbon materials during synthesis with their subsequent use as an electrode material for electric double-layer capacitors. It has been established a multilayer neural network can be used to predict the sorption properties of nanoporous carbon materials. A multilayer neural network confirms the experimental dependences of the characteristics of nanoporous carbon materials porous structure on the technological conditions of its obtaining.

Bulk-synthesis and supercapacitive energy storage applications of nanoporous triazine-based graphdiyne

Heteroatom doping and well-tuned porosity are regarded as two important pathways to enhance energy storage performance of porous carbon materials (PCMs). In this context, N-doped triazine-based graphdiyne (TGDY) and its hydrogen-containing counterpart HGDY were bulk-synthesized by Glaser coupling reaction from multi-acetylene monomers M1 and M2 respectively. TGDY exhibits a two-dimensional layer-by-layer structure and a high specific BET surface area of 785 m2 g−1. After heat-treatment at an optimized temperature of 800 °C, TGDY-800 shows a high specific capacitance of 250 F g−1 at 0.1 A g−1 and a remarkable capacitance retention of 97.6% at 1 A g−1 after 10,000 cycles. These results are superior to HGDY-800 with similar structural skeleton and many other N-doped PCMs, indicating the synergetic effect of N-doping and high surface area. This work could effectively cast insight into designing of nanoporous carbon materials with good energy storage performance.

Nanoporous Carbon Materials Derived from Washnut Seed with Enhanced Supercapacitance.

Nanoporous activated carbons-derived from agro-waste have been useful as suitable and scalable low-cost electrode materials in supercapacitors applications because of their better surface area and porosity compared to the commercial activated carbons. In this paper, the production of nanoporous carbons by zinc chloride activation of Washnut seed at different temperatures (400–1000 °C) and their electrochemical supercapacitance performances in aqueous electrolyte (1 M H2SO4) are reported. The prepared nanoporous carbon materials exhibit hierarchical micro- and meso-pore architectures. The surface area and porosity increase with the carbonization temperature and achieved the highest values at 800 °C. The surface area was found in the range of 922–1309 m2 g−1. Similarly, pore volume was found in the range of 0.577–0.789 cm3 g−1. The optimal sample obtained at 800 °C showed excellent electrochemical energy storage supercapacitance performance. Specific capacitance of the electrode was calculated 225.1 F g−1 at a low current density of 1 A g−1. An observed 69.6% capacitance retention at 20 A g−1 indicates a high-rate capability of the electrode materials. The cycling stability test up to 10,000 cycles revealed the outstanding stability of 98%. The fascinating surface textural properties with outstanding electrochemical performance reveal that Washnut seed would be a feasible agro-waste precursor to prepare nanoporous carbon materials as a low-cost and scalable supercapacitor electrode.

Solvent-free synthesis of N-doped nanoporous carbon materials as durable high-performance pH-universal ORR catalysts

Metal-free carbons as durable high-performance oxygen reduction electrocatalysts, deemed to be promising alternatives to the platinum-group metals (PGMs), are vital to large-scale commercialization of fuel cells. Herein, a solvent-free synthetic strategy has been proposed to prepare N-doped nanoporous metal-free carbonaceous materials originating from various types of plant residues (papaya skin – fruit, bamboo shoot – forestry, wheat straw – farming and cabbage stem – vegetable). The optimal metal-free carbon, possessing maximized reaction surface area and optimized distributions of nanopore structures and nitrogen species, can function as the durable high-performance pH-universal ORR electrocatalyst, reaching or surpassing the benchmark 20% Pt/C catalyst within the wide scope of pH. This paper substantiates the solvent-free, scalable and bio-universal preparation approach to converting various biomass wastes into durable high-performance pH-universal ORR carbonaceous catalysts, capable of expanding the repertoire of cathode catalysts employed by fuel cells that demand diverse pH environments.

Fast Ion Diffusion in Carbon Nanotube Channels

Many simulations and experiments have investigated pressure-driven fluid flow in carbon nanotubes (CNTs) and demonstrated enormous transport rates through these channels. Comparatively little attention has been given so far to concentration-driven transport1,2 in CNTs despite its importance in a large variety of fields. While several studies assumed bulk/hindered diffusion for small molecules through nm-wide CNTs, other simulations have predicted self-diffusion coefficients several times larger than in the bulk. These large uncertainties in the magnitude of the diffusion rates through CNTs have hampered their full exploitation in nanofluidic devices.3 To obtain a precise quantification of the diffusive flow in CNTs, we have fabricated membranes with a large but known number of single-walled carbon nanotubes (SWCNT) as fluid transport pathways. Contrary to previous membrane systems, this platform enables us to minimize uncertainties in the calculation of the per-pore flow rate. A series of stringent control experiments confirms that these membranes are defect free and that transport occurs only through SWCNTs. Once corrected for the boundary layer resistance at the membrane/fluid interface, our measurements reveal that the transport diffusivity of small ions in single-walled carbon nanotubes is one order of magnitude faster than in the bulk.4 The dependence of the flow enhancement on the ion chemico-physical properties is also discussed. Together with indicating that CNT membranes could enable dialysis processes with unprecedented efficiency, these results have important implications for a broad range of applications, such as energy storage/harvesting and chemical separation/detection, where ion permeation through nanoporous carbon materials is key.

Nanoporous carbon hybrids derived from polymethylsilsequioxane for ultracapacitor electrodes

A nanoporous carbon hybrid with high specific surface area (SSA) and pore volume was processed in a novel two-step approach using nanocarbon and a commercial preceramic polymer. First, nanocarbon was coated with a methylsilsesquioxane based preceramic polymer, crosslinked, and pyrolyzed to obtain silicon oxycarbide (SiOC) coated nanocarbon hybrid. Further, selective etching of the SiO 2 nanodomains from the SiOC coating in the ceramic-carbon hybrid resulted a nanoporous carbon materials with excellent SSA of 1400 m 2 g −1 , and pore size distribution in the range of 1–4 nm. Preliminary investigations on the synthesized carbon hybrid with cyclic voltammetry exhibited typical rectangular voltammogram without any faradaic contribution, and high specific capacitance of 227 F g −1 at a scan rate of 20 mV s −1 . • A nanoporous carbon hybrid with excellent specific surface area (SSA) and pore volume was processed in a novel two-step approach using nanocarbon and polymethylsilsesquioxane preceramic polymer. • The SSA of the hybrid was 1400 m 2 g −1 and pore volume of 0.84 cm 3 g −1 with hierarchical porosity in microporous (<2 nm) and lower mesoporous (2–4 nm) range. • Preliminary investigations with cyclic voltammetry exhibited almost rectangular voltammogram and clear EDLC behavior without any contribution of faradaic reactions. • High specific capacitance of 227 F g −1 for the carbon hybrid was obtained at a medium range scan rate of 20 mV s −1 . • These results are bound to open up an area of exploring nanoporous materials for ultracapacitor electrodes from other commercial preceramic polymers following the process described in this manuscript.

Membrane and electrode engineering of high-performance lithium-sulfur batteries modified by stereotaxically-constructed graphene

Lithium-sulfur batteries have great potential as the next-generation clean energy storage systems due to their remarkable high-energy density and electrochemical capacity. Additionally, sulfur is used as a cathode material because of its characteristics of a low cost, environmental friendliness, and abundant nature. However, the polysulfide shuttle effect decreases the electrochemical performance of lithium-sulfur batteries. Here, a rational membrane/electrode design has been applied to lithium-sulfur batteries. A three-dimensional hierarchical nanoporous carbon material derived from cationic resins in a cost-effective process was synthesized at a high temperature and utilized as an intermediate layer to improve the rate capability and cycle stability of lithium-sulfur batteries. Furthermore, stereotaxically -constructed multiporous graphene with a high conductivity (1.6 × 10 3 S m −1 ), porosity and large specific surface area (824 m 2 g −1 ) has been applied in the cathode to increase the conductivity of sulfur, improve the transport of lithium-ions and increase the contact with the electrolyte. In particular, stereotaxically-constructed multiporous graphene was used as the sulfur carrier (sulfur loading 70 wt %). The electrochemical results revealed an initial discharge capacity of the hierarchical nanoporous carbon material intermediate layer-coated membrane of 1008 mAh g −1 at 0.5C, and the reversible capacity was 532 mAh g −1 at 1C after 300 cycles. Based on the experimental evidence and analyses, we concluded that the enhanced performance is due to the confinement of lithium polysulfides by the micropores and mesoporous structure of the hierarchical porous carbon material and the increased transportation of lithium ions and the improved wettability of membrane by electrolyte. • Hierarchical nanoporous carbon material (HNCM) has been synthesized at a high temperature by a cost-effective process. • The HNCM reduce the interfacial resistance and increase the wettability of membrane by electrolyte. • The stereotaxically-constructed multiporous graphene (SCMG) employed as sulfur host for Li–S batteries. • The resultant lithium-sulfur batteries exhibit a superior rate capacity and improved cycling capacity. • The multiple physical sorption of the modified layer greatly inhibit the shuttling of polysulfide.

High Surface Area Nanoporous Graphitic Carbon Materials Derived from Lapsi Seed with Enhanced Supercapacitance.

Nanoporous activated carbon materials derived from agro-wastes could be suitable low-cost electrode materials for high-rate performance electrochemical supercapacitors. Here we report high surface area nanoporous carbon materials derived from Lapsi seed agro-waste prepared by zinc chloride (ZnCl2) activation at 700 °C. Powder X-ray diffraction (pXRD) and Raman scattering confirmed the amorphous structure of the resulting carboniferous materials, which also incorporate oxygen-containing functional groups as confirmed by Fourier transform infrared (FTIR) spectroscopy. Scanning and transmission electron microscopy (SEM and TEM) analyses revealed the granular, nanoporous structures of the materials. High-resolution TEM (HR-TEM) confirmed a graphitic carbon structure containing interconnected mesopores. Surface areas and pore volumes of the materials were found, respectively, in the ranges from 931 to 2272 m2 g−1 and 0.998 to 2.845 cm3 g−1, and are thus superior to commercially available activated carbons. High surface areas, large pore volumes and interconnected mesopore structures of these Lapsi seed-derived nanoporous carbon materials lead to their excellent electrochemical supercapacitance performance in aqueous electrolyte (1 M H2SO4) with a maximum specific capacitance of 284 F g−1 at a current density of 1 A g−1. Furthermore, the electrodes showed high-rate capability sustaining 67.7% capacity retention even at high current density of 20 A g−1 with excellent cycle stability achieving 99% capacitance retention even after 10,000 charge–discharge cycles demonstrating the potential of Lapsi seed derived nanoporous carbons as suitable electrode materials in high-performance supercapacitor devices.

Use of new nanoporous carbon produced from Mandarin (Citrus reticulata) industrial processing waste to remove anionic and cationic dyes

ABSTRACT The present study is concerned with the use of a novel nanoporous carbon material (MNC) produced from mandarin (Citrus reticulata) industrial processing waste (MW) for the removal of textile dyes as cationic dye, methylene blue (MB) and anionic dye, metanil yellow (MY), from the aqueous solution. The adsorption mechanisms were examined by SEM and FT-IR analysis. For two dyes, the kinetics was well described by the pseudo-second-order model, whereas the isotherms were all best-fitted by the Langmuir model, and the maximum monolayer adsorption capacity for MB and MY dyes were 313 and 455 mg g−1, respectively.

Controllable preparation and functionally graded programming of carbon aerogel

PurposeThe purpose of this work is to controllably synthesize a carbon aerogel with programmable functionally graded performance via a simple and effective strategy.Design/methodology/approachThis work uses polyvinyl alcohol (PVA) via the controllable sol-gel, lyophilization, and carbonization approach to achieve a programmable carbon aerogel. This design has the advantages of low raw material and preparation cost, simple and controllable synthetic process and low carbonization temperature.FindingsThe thermal stability and microstructure of PVA aerogel can be controlled by the crosslinking agent content within a certain range. The crosslinking agent content and the carbonization temperature are the key factors for functionally graded programming of carbon aerogels, including microstructure, oxygen-containing functional groups and adsorption performance. The adsorption ratio and adsorption rate of uranium can be controlled by adjusting initial concentration and pH value of the uranium solution. The 2.5%25 carbon aerogel with carbonization temperature of 350 °C has excellent adsorption performance when the initial concentration of uranium solution is 32 ppm at pH 7.5.Research limitations/implicationsAs a new type of lightweight nano-porous amorphous carbon material, this carbon aerogel has many excellent properties.Originality/valueThis work presents a simple, low cost and controllable strategy for functionally graded programming of novel carbon aerogel. This carbon aerogel has great potential for application in various fields such as uranium recovery, wastewater treatment, sound absorption and shock absorption.

Nanoarchitectonics of Nanoporous Carbon Materials in Supercapacitors Applications.

High surface area and large pore volume carbon materials having hierarchical nanoporous structure are required in high performance supercapacitors. Such nanoporous carbon materials can be fabricated from organic precursors with high carbon content, such as synthetic biomass or agricultural wastes containing cellulose, hemicellulose, and lignin. Using recently developed unique concept of materials nanoarchitectonics, high performance porous carbons with controllable surface area, pore size distribution, and hierarchy in nanoporous structure can be fabricated. In this review, we will overview the recent trends and advancements on the synthetic methods for the production of hierarchical porous carbons with one- to three-dimensional network structure with superior performance in supercapacitors applications. We highlight the promising scope of accessing nanoporous graphitic carbon materials from: (i) direct conversion of single crystalline self-assembled fullerene nanomaterials and metal organic frameworks, (ii) hard- and soft-templating routes, and (iii) the direct carbonization and/or activation of biomass or agricultural wastes as non-templating routes. We discuss the appealing points of the different synthetic carbon sources and natural precursor raw−materials derived nanoporous carbon materials in supercapacitors applications.

Electrochemical properties of nanoporous carbon materials obtained from raw materials of plant origin (hemp shives)

The paper reveals the results of electrochemical studies of activated nanoporous carbon material (NPC) as an electrode material for electrochemical capacitors (EC), the charge of which is accumulated in an electrical double layer (EDL). NPC material has been obtained from raw material of plant origin (hemp shives) by thermochemical activation using phosphoric acid. It has been established that there is an optimal ratio between the amount of acid and precursor based on plant biomass that is equal to 0.75:1. The specific surface area of ​​the obtained NPCwas ~ 2000 m2/g, and the maximum specific capacitance of EC models based on them was ~ 113 F/g. At the same time, the contribution of the EDL capacitance to the total capacitance is 60-80 %.

Sugarcane vinasse-derived nanoporous N-S-doped carbon material decorated with Co: A new and efficient multifunctional electrocatalyst

Vinasse has been successfully used as carbon and non-metals precursor for the synthesis of N-S-doped nanoporous carbon materials. The procedure involves the hydrothermal treatment of vinasse (HTV), and subsequent physical activation with CO2 in absence (VP) and presence of cobalt (VPCo). The N2 physisorption and SEM images showed the development of porous in the material, with BET surface area values ranging from 7.17 (HTV) to 734 m2 g−1 (VPCo), and the formation of carbon-spheres. Spectroscopy techniques (FTIR and XPS) demonstrated the insertion of nitrogen and sulfur elements, as well as the presence of cobalt into the carbon lattice. The electrocatalytic activity experiments toward the oxygen reduction and evolution reactions, and hydrazine oxidation reaction were superior for VPCo, which gave onset values of 0.91, 1.60 and 0.36 V vs. RHE, respectively. Additionally, VP was selective for H2O2, while VPCo catalyzed ORR via a four-electron pathway.

Nitrogen-doped microporous carbon material decorated with metal nanoparticles derived from solid Zn/Co zeolitic imidazolate framework with high selectivity for CO2 separation

To enhance CO2 separation selectivity and adsorption capacity for CCS applications, a core-shell Zn/Co zeolitic imidazolate framework (ZIF) synthesized through solvent-thermal reactions at 120 ℃ was pyrolyzed at different temperatures (ranging from 600 to 725 ℃) to obtain nanoporous carbon (NPC) materials with increased metal-N2 active sites and enhanced moisture stability. The NPC sample pyrolyzed (at 725 ℃) showed the highest CO2 uptake (3.22 mmol/g at 273 K and 1 bar), which was 2.13 times higher than that of the raw core-shell Zn/Co ZIF. In addition, it also exhibited the highest heat of adsorption towards CO2 (40 kJ/mol) and superior moisture stability compared to the other samples. Ideal adsorbed solution theory (IAST) calculations showed that this sample also possessed the highest CO2 separation selectivities of 24.3 and 40.2 for model biogas (CO2/CH4, volume ratio = 40:60) and coal-fired flue gas (CO2/N2, volume ratio = 15:85) mixtures, respectively, which were much higher than the corresponding values (2.11 and 3.71) for the raw core-shell Zn/Co ZIF. Through a combination of XPS, FTIR, PXRD, N2 adsorption-desorption, SEM, and TEM experimental techniques, it was demonstrated that the unsaturated metal sites (Me-N2) and pyridinic nitrogen groups were dominant active sites for CO2 adsorption via strong electrostatic interactions. The results obtained herein demonstrate that nitrogen-doped NPCs derived from core-shell Zn/Co ZIF are promising solid CO2 separation materials for industrial power plant flue gas and biogas purification applications.

Influence of Acid Additive on Nanoporous Carbon Materials via HTC for Catalyst Support

Abstract Nanoporous carbon materials were successfully synthesized via hydrothermal carbonization with acid additives. In this study the effect of hydrothermal temperature (160-200 °C), hydrothermal time (4-24 h) and influence of acid additive (HCl, HNO3, H2SO4 and H3PO4) have been chosen in order to improve the surface structure. The samples have been characterized by scanning electron microscopy, nitrogen sorption, Fourier transform infrared spectroscopy and X-ray diffraction. The experimental results revealed that hydrothermal carbonization process and acid addition have effect on the properties of catalyst support. The results indicated that hydrothermal process at 200°C for 12 h and activation with H3PO4 at 900 °C for 2 h, exhibited the highest surface area, porosity and pore volume leading to increased distribution of metal on the carbon support

Особенности синтеза нанопористого углеродного материала

Creation of innovative products and technological breakthrough – phrases most often used in relation to objects located in the nanoscale area. Carbon nanomaterials (CNMs) of various morphologies and structures, which include nanotubes, graphene, nanoporous carbon, are one of the most studied materials of the nanotechnology industry at present. This is due primarily to the fact that their physico-mechanical and physico-chemical characteristics have a direct effect on the final product. At the same time, for a number of applications, the best performance is achieved at the highest possible values of specific surface parameters and porosity. Methods and an experimental technology for producing micro- and mesoporous carbon material have been developed. Depending on the feedstock and technological synthesis modes, a nanoporous carbon material is obtained with a predominance of micro- or mesopores, with a BET specific surface area in the range of 2000–4000 m2/g. The technology includes carbonization of the starting materials and subsequent chemical activation. The obtained activated carbon material can be used as sorbents for gaseous media, both in purification systems and as gas batteries for safe storage and transportation systems, as well as for solving a number of environmental problems.

Nanoporous carbon for electrochemical capacitive energy storage.

The urgent need for efficient energy storage devices has stimulated a great deal of research on electrochemical double layer capacitors (EDLCs). This review aims at summarizing the recent progress in nanoporous carbons, as the most commonly used EDLC electrode materials in the field of capacitive energy storage, from the viewpoint of materials science and characterization techniques. We discuss the key advances in the fundamental understanding of the charge storage mechanism in nanoporous carbon-based electrodes, including the double layer formation in confined nanopores. Special attention will be also paid to the important development of advanced in situ analytical techniques as well as theoretical studies to better understand the carbon pore structure, electrolyte ion environment and ion fluxes in these confined pores. We also highlight the recent progress in advanced electrolytes for EDLCs. The better understanding of the charge storage mechanism of nanoporous carbon-based electrodes and the rational design of electrolytes should shed light on developing the next-generation of EDLCs.

ZIF-11 derived nanoporous carbons with ultrahigh uptakes for capture and reversible storage of volatile iodine

In this work, three nanoporous carbon materials Z11-700, Z11-800 and Z11-900 were synthesized by a one-step calcination of zeolitic imidazolate framework-11 (ZIF-11) at 700, 800 and 900 ​°C, respectively. The samples obtained were characterized by SEM, PXRD, FT-IR, Raman spectra and N2 adsorption. The results showed that the three ZIF-11 derived samples were micro/mesoporous and had high BET surface areas and pore volumes. Of the synthesized samples, Z11-900 displayed an excellent iodine vapour uptake of 3775 ​mg/g which was superior compared with Z11-700 and Z11-800, as well as other reported solid state materials. What is more, the regeneration efficiency of Z11-900 for iodine molecules was near to 90% (3672 ​mg/g) after three cycles of reuse. The easy operation, highly-effective and recyclable features enable the ZIF-11 derived nanoporous carbons to be a promising adsorbent for applications in environmental remediation.

Performance of nanoporous carbon material derived from Cocos nucifera: An approach for the recovery of nickel using continuous operation

Heavy metals pollution has become one of the serious environmental problems nowadays. The removal of heavy metals from the environment is of special concern due to their persistence. Activated carbon (AC) was synthesized using Exocarp of Cocos nucifera (ECN) as the precursor with H3PO4 as the chemical activating agent with impregnation ratio of 1:1 and 2:1. The adsorption behaviour of Ni from aqueous systems onto AC prepared from ECN has been attempted for column studies under various operating conditions. The regeneration studies were carried out for four adsorption–desorption cycles. Based on the results, activated ECN (AECN) can be economically and effectively used as an adsorbent for the removal of Ni from wastewaters.