간행물

Carbon Letters KCI 등재 Carbon letters

권호리스트/논문검색
이 간행물 논문 검색

권호

Vol.32 No.7 (2022년 12월) 15

1.
2022.12 구독 인증기관 무료, 개인회원 유료
Due to their fascinating properties, there is a rise in the critical consideration of carbon-based nanomaterials in a plethora of applications. Carbon nanomaterials, such as nanotubes, graphene, fullerenes, and nanodiamonds, have broad applicability and potential research prospects. In the past few years, the developments and consumption of still smaller nanomaterials, namely graphene quantum dots and carbon nanodots or carbon dots (CDs) have been explored. Since carbon as a component exhibits insignificant cytotoxicity and remarkable biocompatibility, CDs have found a wide scope of potential applications. Owing to their fascinating aspects, such as small size, biocompatibility, low toxic nature, environment-friendliness, costeffectiveness, ease of chemical functionalization, derivatization and surface modification, and photoluminescence tenability, CDs have been widely acknowledged. CDs have found major prospects in the areas of catalysis, sensors, and optical and bio-related applications. CDs are generally synthesized by employing techniques of pyrolysis, laser ablation, arc discharge, electrochemical method; hydrothermal and solvothermal techniques; and microwave and ultrasonic irradiations. This review article presents a brief account of the major properties of CDs, and applications, with particular emphasis on the green and environment-friendly synthesis methodologies. An overview of the microwave and ultrasound irradiation-induced syntheses for the preparation of CDs is presented in the light of green chemistry principles. In addition, some of the green and environmentally benign precursors for the production of CDs are outlined. The most recent work on CDs is included in this review article.
6,600원
2.
2022.12 구독 인증기관 무료, 개인회원 유료
Carbon is a part of all living creatures and it is the chief constructing block for life on this planet carbon occurs in several appearances, mainly as plant biomass, organic matter in soil, as gas CO2 in the air and dissipated in seawater. Soil carbon exhausts when production of carbon increases than carbon contribution. Soil comprises nearly 75% of total carbon existing on land, more than the quantity stockpiled in living animals and plants. So, soil plays a major part in maintaining a stable carbon cycle. Over the previous 150-year-period, the quantity of carbon present in the air has amplified by 30%. Majority of scientists thought that there is a straight relationship amongst amplified levels of CO2 in the air and increasing global warming. One anticipated technique to diminish atmospheric CO2 is to escalate the global packing of carbon in soils. Therefore, there is a necessity to manage soils because soil comprises more inorganic carbon as compared to the atmosphere and more organic carbon as compared to the biosphere. Soil is also thought to be a lively and important constituent in global carbon discharge and potential of sequestration. Carbon sequestration, known commonly as C-storage, can be acquired by different controlling practices, and the size of various management techniques, to enhance C-storage of soil and offer a key basin for atmospheric CO2, can be assessed most persuasively from studies conducted over long time that underwrite exclusive data on soil C accumulation, losses and storage. Sequestration happens when input of carbon enhances as compared to output of carbon. Soil carbon sequestration is the method of relocating CO2 from the air in to the soil with crop leftover and additional organic solids and in a configuration that is not instantly emitted back to the atmosphere. This review focused on beneficial role of carbon sequestrating fertilizers (press mud, boiler ash and compost) in carbon sequestration and soil properties.
4,600원
3.
2022.12 구독 인증기관 무료, 개인회원 유료
Nonporous materials have nano-sized pores. High specific surface area and size and shape selectivity (size and shape Selectivity) are the most important features of these materials that have led to their widespread use in various industries, such as catalysts, water treatment and separation of pollutants. The development of properties and applications of these materials depends on the fabrication of nanoporous materials with optimal and controlled structures. In this paper, porous nanostructures and supermolecular chemistry are introduced in detail. Then, a number of common nanoporous materials, such as activated carbon, metal–organic frameworks and zeolites, then various types of mineral and organic nanoporous materials as well as methods of synthesis, characterization and applications of these materials will be studied in detail.
6,300원
4.
2022.12 구독 인증기관 무료, 개인회원 유료
The conversion of CO2 into solar fuels by photocatalysis is a promising way to deal with the energy crisis and the greenhouse effect. The introduction of oxygen vacancy into semiconductor has been proved to be an effective strategy for enhancing CO2 photoreduction performance. Herein, TiO2- x nanostructures have been prepared by a simple solvothermal method and engineered by the reaction time. With the prolonging of reaction time, the oxygen vacancy signal gradually increases while the band gap becomes narrow for the as-synthesized TiO2- x nanostructures. The results show that the TiO2- x-6 h, TiO2- x-24 h, and TiO2- x-48 h samples have the main product of CH4 (more) and CO (less) for CO2 photoreduction. Among the three oxygen vacancy photocatalysts, the TiO2- x-24 h sample shows the highest CH4 generation rate of 41.8 μmol g− 1 h− 1. On the basis of photo/electrochemical measurements, the TiO2- x-24 h sample exhibits efficient electron–hole separation and charge transfer capabilities, thus allows much more electrons to participate in the reaction and finally promotes the photocatalytic CO2 reduction reaction. It further confirms that the optimization of oxygen vacancy concentration could facilitate the photoinduced charge separation and accordingly improve photocatalytic CO2 conversion.
4,000원
5.
2022.12 구독 인증기관 무료, 개인회원 유료
We report the use of face mask materials as a carbon precursor for the synthesis of multi- and single-walled carbon nanotubes (CNTs) in an open-loop chemical recycling process. Novel surgical mask precursors were suspended in toluene and injected into a chemical vapor deposition reactor previously optimized for CNT production using liquid injection. The CNTs were collected and characterized using resonant Raman spectroscopy, transmission electron microscopy (TEM) and scanning electron microscopy (SEM) before being turned into fibrils that were tested for electrical conductance. Once confirmed and repeated for statistical accuracy, a CNT-based Ethernet cable was manufactured and tested using iPerf3 for uplink and downlink speeds exceeding broadband standards worldwide. Radial breathing modes from Raman spectroscopy indicate single walled CNTs (SWCNTs) with diameters ranging from 0.8 to 1.55 nm and this matches well with TEM observations of SWCNTs with 1.5 nm diameter. This work pushes the horizon of feedstocks useful for CNT and SWCNT production in particular; this work demonstrates upcycling of materials fated for disposal into materials with positive net value and plenty of real-world applications.
4,000원
6.
2022.12 구독 인증기관 무료, 개인회원 유료
In this study, UiO-66-NH2 was synthesized and incorporated with graphene aerosol (UiO-66-NH2/GA) and ethylenediamine functionalized graphene oxide (UiO-66-NH2/GO-NH2). These composites were characterized using infrared spectroscopy, powder X-ray diffraction, ultraviolet–visible light spectroscopy, scanning electron microscope, and energy-dispersive X-ray spectroscopy. UiO-66-NH2/GO-NH2 exhibited 93% adsorption of quinoline in 5 h, UiO-66-NH2 and UiO-66-NH2/GA presented 80.4% and 86.5%, respectively. The high adsorption observed on UiO-66-NH2/GO-NH2 was attributed to the unique electronic properties, and hydrogen bonding between the nitrogen atom of quinoline and NH2- phenyl fragment of UiO-66-NH2, and N–H of ethylenediamine. GO also offered combined strong π–π interactions on its surface, and the oxygen coverage (~ 50%) on GO within the structure is responsible for the formation of strong hydrogen bonds with quinoline. Theoretical calculation suggested that UiO-66-NH2/GO-NH2 presented a more favourable adsorption energy (− 18.584 kcal/ mol) compared to UiO-66-NH2 (− 16.549 kcal/mol) and UiO-66-NH2/GA (− 13.991 kcal/mol). These results indicate that nanocomposites have a potential application in quinoline capture technologies in the process of adsorptive denitrogenation.
4,600원
7.
2022.12 구독 인증기관 무료, 개인회원 유료
Magnetically separable and reusable zinc ferrite/reduced graphene oxide ( ZnFe2O4/rGO) nanocomposite has been prepared by hydrothermal method. The results illustrate that the construction of ZnFe2O4 and rGO occur concurrently in a hydrothermal reaction that initiates the formation of rGO-wrapped ZnFe2O4 nanospheres. The morphological and structural features of the ZnFe2O4/ rGO nanocomposites reveal that the rGO nanosheets anchored to the ZnFe2O4 sphere act as a self-protective clamping layer to avoid the photo corrosion effect under photo irradiations. The nanocomposites express the soft magnetic behavior with high saturation magnetization under annealing temperature at 300 °C, which may attribute to the well-defined crystalline structure and surface defects. In addition, the GZF 300 nanocomposites exhibit the enhanced photocatalytic degradation over Rhodamine B dye which is 3.4, 1.15, and 1.32 times higher than that of ZF, GZF, and GZF 600 over under visible irradiation in 120 min. The GZF 300 nanocomposites demonstrate their ability to degrade RhB efficiently, even after several photocatalysis cycles with high catalyst recovery by its magnetically separable behavior. The high densities of oxygen defects improvise electron transfer from ZnFe2O4 to rGO and delay the recombination process of the nanocomposite, resulting in enhanced visible photocatalytic activity. The strong magnetic properties of rGO wrapped ZnFe2O4 nanocomposite catalysts the easy separation from the suspension system for multiple usages in water treatment.
4,300원
8.
2022.12 구독 인증기관 무료, 개인회원 유료
Since soil salinization imposes various adverse effects on plants, research on how to relieve salt stress from plants is extremely urgent. We synthesized a new type of cerium-doped carbon quantum dots by a hydrothermal synthesis method. Characterization shows that the carbon quantum dots have a small and uniform particle size, high stability, high water solubility and biocompatibility. Mung bean seeds were soaked in CDs:Ce solutions under a concentration gradient (0.25, 0.5, 1, 2, 3 mg/ mL) and germinated under salt stress (150 mM NaCl). Compared with salt stress, the addition of CDs solutions effectively enhanced the ability of plants to relieve salt stress. The relieving effect on mung bean plants was the most significant after treatment with 2 mg/mL CDs:Ce, and the main root length, plant height and leaf length in comparison with the case of salt stress increased by 83%, 80%, and 60%, respectively. Chlorophyll content, peroxidase activity, superoxide dismutase activity and catalase activity, total protein content increased by 90%, 77%, 76%, 77% and 76%, respectively, malondialdehyde and proline The content decreased by 83% and 77%. Inductively coupled plasma mass spectroscopy proved mung bean plants absorbed CDs:Ce, but the absorption of NaCl decreased by 21.8%. Fluorescence imaging showed CDs:Ce was absorbed by roots, and transferred from the vascular system and apoplastic pathways to stems and leaf veins, and mainly aggregated in intercellular gaps, the vascular system, leaf veins, cilia and stomata. Stereomicroscopy showed that CDs:Ce induction increased the stomatal opening by 15.7%, and improved metabolic efficiency and NaCl excretion from the plants. Hence, CDs:Ce shows great potential in protecting crops from abiotic stress.
4,500원
9.
2022.12 구독 인증기관 무료, 개인회원 유료
Different materials have been shown to "catalyze" carbon nanotube (CNT) growth in chemical vapor deposition (CVD) when they become nano-sized particles. Catalysts, which act as a kind of "seed" for CNT growth, show two types of behavior in the CVD method; precipitation of carbon atoms from the eutectic alloy forming a kind of alloy with carbon; the fact that the catalyst remains as a solid phase and forms a carbon surface layer during the CVD process. This study examines the relationship between the iron-group and non-iron-group catalyst types and the catalyst concentration and growth time of CVD-based CNT growth via emphasizing growth mechanisms. The novelty of this work is to compare and evaluate the effects of catalyst type, concentration, and growth time, which are three critical CVD parameters, on the final nanotube morphology. It was utilized five different catalysts ( Fe2O3, Fe3O4, Nb2O5, Au, and Pt), three different growth durations (3, 5, and 7 min), and three different catalyst concentrations (2, 4, and 6 wt%) to explore the morphological differences on CNT synthesis by CVD under the same process parameters. The results demonstrated that catalyst type is the most influential parameter in CVD-based CNT synthesis, while catalyst concentration and growth time are indispensable elements for the uniformity and small diameter in the final morphology.
4,800원
10.
2022.12 구독 인증기관 무료, 개인회원 유료
Commercial carbon fiber cloth (CFC) is treated by the Joule-heating pyrolysis method in air to boost its capacitive performance on the premise of energy- and time-saving considerations. A thermoelectric coupling model suitable for the Jouleheating pyrolysis is successfully established based on the comparisons between the simulated temperatures and actually measured ones. The temperature field on CFC surface induced by the Joule heat presents a concentric-ellipse shape that the temperature in the core is the maximal and gradually decays outward. Increasing the direct current (DC) voltage which is applied to the CFC from 1.0 to 6.0 V, the core temperature on the CFC surface can be raised from 31 to 519 °C. The specific surface area and hydrophilicity of the as-prepared porous CFC are greatly improved compared with the pristine one. Electrochemical test shows that the optimal Joule-heating pyrolysis parameters falls at 5.0 V and 12.5 min, and the areal specific capacitance of as-obtained CFC-5.0-12.5 is about 80 folds that of the pristine CFC. In addition to the much shorter preparation time, all the characteristics including areal specific capacitance, rate performance, and electrical conductivity of the Joule-heating pyrolyzed CFC are superior to those of the electrical furnace pyrolyzed counterpart. The aqueous symmetrical supercapacitor made of CFC-5.0-12.5 electrodes exhibits considerable power and energy densities with respect to the previously reported carbon electrode-based supercapacitors. For conductive precursors, the Joule-heating pyrolysis can be an ideal substitute for the traditional electric furnace pyrolysis.
4,300원
11.
2022.12 구독 인증기관 무료, 개인회원 유료
Doping graphene to epoxy resins can improve the protective ability of the coating, but the lack of active anticorrosion function greatly limits its application in the field of anticorrosion. Herein, N/S-rich few-layer-graphene (N/S-FLG) was prepared and adopted to endow epoxy coating with dual passive/active corrosion protection. The obtained amphiphilic N/S-FLG is highly dispersed in the epoxy coating, giving rise to the enhanced hosting effect for graphene defects, avoiding the interface corrosion and blocking the penetration of corrosive species. Furthermore, the doping of N and S endows graphene sheets favourable catalytic ability for corrosive oxygen, actively eliminating its contribution to metal corrosion. Under this dual effect, the passive and active anticorrosion properties of epoxy coating are simultaneously enhanced. The coating with 1 wt% N/S-FLG reduces the corrosion rate of metal to 6.5 × 10– 5 mm/a, exhibiting almost no corrosion. The proposed concept of introducing nanocatalytic N/S-FLG is facile and eco-friendly, and will undoubtedly promote the practical application of anticorrosion coatings.
4,600원
12.
2022.12 구독 인증기관 무료, 개인회원 유료
The evolvement in the microstructure and electrical properties of PAN-based carbon fibers during high-temperature carbonization were investigated. The study showed that as the heat treatment temperature increases, the change of carbon fiber resistivity around 1100 °C can be divided into two stages. In the first stage, the carbon content of the fiber increased rapidly, and small molecules such as nitrogen were gradually released to form a turbostratic of carbon crystal structure. The resistivity dropped rapidly from 3.19 × 10− 5 Ω·m to 2.12 × 10− 5 Ω·m. In the second stage, the carbon microcrystalline structure gradually became regular, and the electron movement area gradually became larger. At this time, the resistivity further decreases, from 2.12 × 10− 5 Ω·m to 1.59 × 10− 5 Ω·m. During carbonization, the tensile strength of carbon fiber first increased and then decreased. This is because the irregular and disordered graphite structure is formed first. As the temperature rose, the graphite layer spacing decreased and the grain thickness gradually increases. The modulus also gradually increased.
4,000원
13.
2022.12 구독 인증기관 무료, 개인회원 유료
Benzene, toluene, ethylbenzene, and xylenes are commonly known as (BTEX) and include volatile organic compounds (VOCs) in ambient air. Exposure to some BTEX has been associated with health risks. This study aimed to reduce BTEX on the environment and human health dramatically. This research targeted decreasing the BTEX in an air environment by producing high surface area activated carbon (KA-AC) under optimized synthesis conditions from Ricinus communis as lignocellulosic waste using ZnCl2 solution, respectively. The influence of several activation parameters was investigated on the surface area, such as impregnation ratio, carbonization time, and carbonization temperature. The KA5-AC prepared under optimized conditions showed BET surface area and total pore volume of 1225 m2/ g, and 0.72 cm3/ g, respectively. The optimized synthesis conditions were as follows: 0.1, 0.5, 1, 2, and 5 M impregnation ratio, 450–950 °C carbonization temperature, and 100 min carbonization time. The characteristics of the optimized KA-AC were analyzed using nitrogen adsorption–desorption isotherm, scanning electron microscopy, and pore structural analysis. The results confirmed that the VOCs adsorption on KA-AC followed a monolayer adsorption isotherm over a homogeneous adsorbent surface. It showed the removal efficiency of benzene, toluene, ethylbenzene, and m, p-xylene (R2 = from 0.991 to 0.997). Moreover, the KA-AC exhibited good performance without considerable loss of efficacy throughout the experiments. Accordingly, it is concluded that developing low-cost activated carbon to use BTEX vapor adsorption research could be practical and developments to overcome for utilization in air pollution control.
4,000원
14.
2022.12 구독 인증기관 무료, 개인회원 유료
A facile and efficient method was developed to prepare highly stretchable and conductive graphene conductors with wrinkled structures by the mechanical stretching and shrinking of elastomeric substrates, in which graphene inks were printed on a prestretched elastomeric substrate. Stretchable and exfoliated graphene inks were prepared by mixing graphite and Ecoflex in a shear-assisted fluid dynamics reactor. The resultant graphene conductor exhibited excellent stretchability at 150% strain and high electrical conductivity of 64 ± 1.2 S m− 1. The resistance of the conductor did not change in bent, twisted, and stretched states. The resistance did not change during 10,000 cycles of stretching/releasing, with a maximum strain of 150%. Based on the graphene conductor, a stretchable conductometric sensor with a two-electrode configuration was fabricated to measure impedance changes at different concentrations of electrolyte ions. This sensor exhibited a good and linear sensitivity curve (298.61 Ω mM− 1, R2 = 0.999) in bent and stretched states.
4,000원