Carbon Letters最新文献

Carbon-based materials, particularly graphite, have been extensively studied for their potential in fabricating flexible conductive fabrics with high electrical conductivity, which are attractive for wearable electronics. In this study, we investigated the effects of polar solvents, graphite concentration, and temperature on the electrical properties of conductive cotton fabrics. Our results show that the type of polar solvent and graphite concentration strongly influence the electrical conductivity of the fabrics. By controlling the graphite concentration, a wide range of conductive cotton fabrics with different conductivity values can be produced. Additionally, temperature resistance studies revealed that the fabrics exhibit both semiconductor and metallic behavior in the temperature range from room temperature to 160 °C. These interesting properties make the conductive cotton fabrics suitable for use as electrical components in circuits with resistive and inductive loads. Furthermore, we fabricated a supercapacitor with electrodes based on dispersed graphite and an electrolyte of sodium chloride salt dissolved in deionized water. Our findings suggest that conductive cotton fabrics have great potential for use in high-performance wearable electronics and energy storage devices.

N-doping content and configurations have a significant effect on the electrochemical performance of carbon anodes. Herein, we proposed a simple method to synthesize highly N self-doped chitosan-derived carbon with controllable N-doping types by introducing 2ZnCO₃·3Zn(OH)₂ into the precursor. The as-synthesized NC-CS/2ZnCO₃·3Zn(OH)₂ electrode exhibited more than twice the reversible capacity (518 mAh g⁻¹ after 100 cycles at 200 mA g⁻¹) compared to the NC-CS electrode, superior rate performance and outstanding cycling stability. The remarkable improvement should be mainly attributed to the increase of N-doping content (particularly the pyrrolic-N content), which provided more active sites and favored Li⁺ diffusion kinetics. This study develops a cost-effective and facile synthesis route to fabricate high-performance N self-doped carbon with tunable doping sites for rechargeable battery applications.

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Carbon dots (CDs) are versatile nanomaterials with tunable luminescent properties. We used a natural plant kaempferol as a carbon source to synthesize multicolor CDs by reacting it with various nitrogen sources. Blue, green, and red CDs (B-CDs, G-CDs, and R-CDs) with emission wavelengths of 445 nm, 510 nm, and 600 nm respectively were successfully synthesized. Their photoluminescence quantum yields of are up to 37.4%, 20.1%, and 30.8%, respectively. Surface analysis revealed abundant nitrogen groups influencing luminescence. B-CDs and G-CDs show excitation-dependent emissions, indicating a potential correlation between their luminescence and particle sizes, while R-CDs exhibit excitation-independent emission, suggesting they belong to molecular state CDs. All three CDs exhibit stable luminescent performance, as well as good salt resistance and photobleaching resistance. The practical application of multicolored CDs in anti-counterfeiting fluorescent inks was further explored. This work offers a straightforward, eco-friendly route to synthesize multicolor CDs.

Accurate and rapid detection of antibiotics is critical for protecting human health and the environment. To this end, we report a novel electrochemical sensor for the simultaneous detection of Levofloxacin (LFX) and Tryptophan (TRP) in dairy samples. Outstanding electrocatalytic activity for the oxidation of LFX and TRP is exhibited by the Activated Nanodiamond (AND) and Ti₃AlC₂ max phase (Ti₃AlC_2max) nanocomposite-modified glassy carbon electrode (Ti₃AlC_2max AND/GCE) featured in our sensor. High selectivity and sensitivity are achieved by the sensor, with limits of detection (LOD) of 20.47 nM and 0.309 μM for LFX and TRP, respectively. Moreover, strong anti-parasite capacity is demonstrated by the developed sensor, making it an excellent candidate for the establishment of a reliable sensing platform for antibiotic detection. Findings suggest that this novel sensor could serve as a valuable tool for monitoring the content of LFX and TRP in dairy samples and enhancing the safety of these products.

In this study, we utilized a multi-step stabilization method, incorporating dry-oxidation, to produce high-density polyethylene (HDPE)-based activated carbon fibers. This stabilization was achieved through electron-beam irradiation, sulfonation, and dry oxidation. The stabilized fibers were carbonized and activated at 900 ℃. The crystallite characteristics of the activated carbon fibers were observed using X-ray diffraction, and their surface morphologies were analyzed through scanning electron microscopy. The textural properties were analyzed using N₂/77 K adsorption–desorption isothermal curves. And leveraging the microdomain model, we explored the influence of these stabilization methods on the HDPE-based activated carbon fibers texture properties. The results show that HDPE fibers treated with sulfonation only at 100 ℃ for 60 min were not sufficiently cross-linked and were completely decomposed during the carbonization stage. However, the sulfonated fibers treated with the new dry-oxidation process maintained their shapes and were successfully activated. The specific surface area of the resulting activated carbon fibers was as much as 2000 m²/g.

Synthesis of extremely competent materials is of great interest in addressing the energy storage concerns. Manganese oxide nanowires (MnO₂ NWs) are prepared in situ with multiwall carbon nanotubes (MWCNT) and graphene oxide (GO) using a simple and effective hydrothermal method. Powder XRD, Raman and XPS analysis are utilized to examine the structural characteristics and chemical state of composites. The initial specific discharge capacity of pure MnO₂ NWs_, MnO₂ NWs/MWCNT and MnO₂ NWs/rGO composites are 1225, 1589 and 1685 mAh/g, respectively. The MnO₂ NWs/MWCNT and MnO₂ NWs/rGO composites showed stable behavior with a specific capacity of 957 and 1108 mAh/g, respectively, after 60 cycles. Moreover, MnO₂ NWs/rGO composite sustained a specific capacity of 784 mAh/g, even after 250 cycles at a current density of 1 A/g showing outstanding cycling stability.

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Sulfamonomethoxine (SMM) is widely used to inhibit Gram-positive and Gram-negative bacteria, and improper use of SMM is detrimental to human health and ecological stability. Therefore, a sensitive determination method is of great importance for monitoring SMM residues in water, meat, milk, eggs, etc. Herein, a Pt-functionalized S-doped graphitic carbon nitride (Pt/S-g-C₃N₄) was constructed for the electrochemical determination of SMM. The as-developed Pt₃/S₃-g-C₃N₄ sensor showed a significant SMM determination performance. The electrochemical oxidation of SMM on Pt₃/S₃-g-C₃N₄/GCE involves two electron transference and was limited by a diffusion process. The as-developed Pt₃/S₃-g-C₃N₄/GCE sensor has good linearity in a wide range of 0.1–120 μmol/L and a remarkably low limit of detection (LOD) of 0.026 μmol/L for SMM determination. In addition, the sensor has high selectivity and anti-interference properties for SMM detection. Furthermore, this Pt₃/S₃-g-C₃N₄/GCE sensor has good reproducibility and stability. Moreover, the recoveries were in the range of 89.6–112.2% for the detection of the SMM in a real sample of egg. The proposed Pt₃/S₃-g-C₃N₄/GCE sensor shows great potential for practical applications in detecting trace amounts of antibiotics.

In order to prevent early distress in asphalt pavement and save on subsequent operational and maintenance costs, modifying asphalt is an effective approach. Styrene–butadiene–styrene (SBS) block copolymers, due to their excellent physicochemical properties, have become a mature and widely used asphalt modifier. Carbon nanotubes (CNTs) possess advantages such as a large specific surface area and high modulus, which, when incorporated into asphalt, can enhance its deformation resistance. To analyze the effect of incorporating CNTs on SBS-modified asphalt (SBS-A), this study analyzed the influence of different CNT concentrations on the high and low-temperature performance and aging properties of SBS-A through penetration, softening point, ductility, dynamic shear rheometry, and short-term aging tests. The optimal CNT concentration was determined to be 1.0%. Furthermore, the changes in the modified asphalt during the aging process were analyzed using infrared spectroscopy.

Porous graphene oxide (P-GO) was successfully synthesized by using a simple glucose mediated hydrothermal method form prepared graphene oxide (GO). Then the P-GO was characterized by X-ray Powder Diffraction (XRD), Fourier-Transform Infrared (FITR), Raman, Brunauer–Emmett–Teller (BET), Field Emission Scanning Electron Microscopy (FESEM) and Transmission Electron Microscopy (TEM) analysis to determine the crystallinity, surface functionality, surface defect, surface area and porous nature of the material. For the comparative properties studies with P-GO, the synthesised GO was also characterised using the aforementioned analytical techniques. The formation of macroporous 2D sheet-like structure of P-GO with pore size diameters of 0.2–0.5 µm was confirmed by FESEM and TEM images. The surface area of P-GO was found to be 1272 m²/g which is much higher compare to GO (i.e., 172 m²/g) because of porous structure. P-GO was used for the adsorptive removal of F⁻ ions from water using batch adsorption method. The highest adsorption occurs in the pH range of 5–7 with maximum adsorption capacity of 1272 mg/g. The experimental data revealed that the adsorption process obeys Langmuir monolayer isotherm model. The kinetic analysis revealed that the adsorption procedure is extremely rapid and mainly fit to the Pseudo-second-order (PSO) model. The effect of co-existing ions on fluoride adsorption capacity by P-GO decreases in the following order: PO₄³⁻ > CO₃²⁻ > SO₄²⁻ > HCO₃⁻ > NO₃⁻ > Cl⁻. The mechanism of adsorption of fluoride onto the P-GO surface includes electrostatic interactions and hydrogen bonding.

Traditional piles used for deep foundation, such as steel, concrete, and timber, are susceptible to corrosion and a reduction in structural capacity over time. This has led to the development of new materials like concrete-filled FRP piles (CFFP). CFFP is a composite pile filled with concrete and covered with a fiber-reinforced plastic (FRP) shell, providing non-corrosive reinforcement and protection to the concrete. As a result, CFFP is a highly promising candidate for implementation in various fields due to its structural advantages and necessity. Compared to traditional concrete piles, CFFP can be installed with less damage and a lower blow range due to its elastic modulus, damping ratio, and specific weight. The bearing capacity of a pile is influenced by various factors, including its stiffness, residual stress, and axial load resistance. Due to competitive pricing, glass fiber has been widely utilized, and there is a growing interest regarding carbon-fiber-reinforced concrete piles due to the excellent mechanical properties of carbon fiber. The remarkable stiffness and strength attributes of carbon fibers are evident in CFRP-confined piles, which present a notably wide range of load-bearing capacities, boasting an ultimate axial load capacity ranging from 500 to 4000 kN. Furthermore, CFFPs have been confirmed to have superior lateral load resistance compared to conventional piles, attributed to the reinforcement provided by FRP materials. Conventional piles face a challenge in that their structural characteristics deteriorate in the corrosive marine environment, with a projected lifespan of less than 20 years. In contrast, the service life of CFFPs is estimated to range from 50 to 75 years.