Carbon Letters最新文献

Enhanced concrete construction through carbon incorporation in nanotechnology-enabled cementitious materials can be achieved using biochar. Biochar is a carbon additive, improving concrete’s mechanical strength and durability while reducing porosity and enhancing sustainability. The objective is to leverage the unique properties of biochar, derived from carbon nanotechnology, to improve mechanical strength durability, and reduce porosity in concrete. By integrating biochar, this research aims to develop a more resilient and environmentally friendly construction material, addressing performance and sustainability challenges in modern concrete construction. However, a significant research gap exists in understanding biochar's long-term effects and optimal concentrations in cementitious matrices. This study seeks to fill this gap by systematically investigating the performance enhancements and material properties imparted by biochar in various concrete formulations. The study demonstrated that incorporating carbon-rich biochar into concrete significantly enhances its structural performance and sustainability. The life-cycle assessment (LCA) of biochar-incorporated concrete reveals significant environmental benefits, highlighting its potential for sustainable construction practices. Integrating biochar into concrete enhances the material’s durability and longevity, reducing the need for frequent repairs and replacements, thus conserving resources. The use of biochar supports sustainable waste management by utilizing agricultural and forestry residues, thereby reducing waste and conserving natural resources. Nanotechnology in concrete, through the use of biochar, improves the material’s mechanical properties, creating a denser and more durable matrix that requires less maintenance. These findings underscore the dual benefits of enhancing concrete performance while promoting environmental sustainability, making biochar-incorporated concrete a promising solution for eco-friendly construction. Optimal biochar concentration at 7% by weight improved compressive strength by 20%, reduced freeze–thaw damage by 80%, and decreased chemical degradation by up to 85%. Additionally, biochar reduced concrete porosity and water absorption, creating a denser and more durable matrix. These results highlight the dual benefits of using biochar for carbon sequestration and improving concrete's mechanical properties, supporting its use in sustainable construction practices.

LiFePO₄/C has been successfully synthesized using surfactant-assisted solid-state reaction method to investigate the effects of non-polar solvents on structural properties and electrochemical performance. Petroleum jelly, oleic acid, and sucrose were used as non-polar solvents, surfactants and carbon sources. The ratio of petroleum jelly and oleic acid were 0.5:1 (LFP A), 1:1 (LFP B), and 2:1 (LFP C). The XRD, FE-SEM, and HR-TEM results show that adding petroleum jelly in LFP C enhances crystallinity and improves the morphology of nanoplates in LiFePO₄ material. The EDS and Raman Spectroscopy tests show that the higher addition of petroleum jelly increases carbon percentage and carbon layer defects. The highest Li-ion diffusion coefficient was calculated by LFP C of 4.21 (times) 10^–15 cm².s⁻¹. Furthermore, the highest discharge test results at 0.1 C of LFP A, LFP B, and LFP C were 125 mAh.g⁻¹, 103 mAh.g⁻¹, and 144 mAh.g⁻¹, respectively. However, C-rate performance shows that the specific capacity of LFP A, LFP B, and LFP C at 5 C were 74 mAh.g⁻¹, 35 mAh.g⁻¹, and 59 mAh.g⁻¹, respectively. The cyclability test results showed that LFP A capacity retention after testing for 100 cycles was better than LFP C, and the lowest stability was obtained by LFP B. The addition of petroleum jelly improved the performance of LiFePO₄/C but resulted in excess carbon in active material which decreased battery stability and specific capacity at high C-rate. Our results suggest that non-polar solvents can be added to LiFePO₄/C synthesis to improve electrochemical performance but less carbon chains must be chosen.

In this paper, poly(glycolic acid–co-DL–lactic acid) (PGDLLA)/poly(ɛ-caprolactone) (PCL) incompatible nanocomposites were combined with multiscale modeling (MSM) in a ratio of 80/20. Since the behavior and mechanical properties of blends depend significantly on the interphase region, the compatibilizer poly(l,l-lactic acid–co-ɛ-caprolactone) (P(lLA-co-ɛ-CL)) was used to improve compatibility and graphene oxide (GO) was used to increase the interphase strength of PGDLLA matrix/PCL. This work was done by mixing solvent to achieve the optimum disperse of GO in the matrix. The investigation of interfacial phenomenon by the theoretical interfacial models is important. Under the assumption of constant modulus and elastic deformation in the zero interface region, the predictions in this region are more unreliable when the calculations of experimental mechanical properties are analyzed in detail. In this study, PGDLLA/P(lLA-co-ɛ-CL)/PCL compounds were compared with the MSM approach to predict the plastic deformation in the stress–strain behavior. In contrast to the hypothesis that a simple look at the interphase area in nanocomposites, a finite element code is proposed to evaluate the efficiency of the interphase area. Both experimental results and FEM analysis showed that Young’s modulus increases by incorporating GO into GO/PGDLLA/P(lLA-co-ɛ-CL)/PCL nanocomposites; the amount of increase for incorporating 1 phr GO is about 61%.

With the emergence of the new energy field, the demand for high-performance lithium-ion batteries (LIBs) and green energy storage devices is growing with each passing day. Carbon nanotubes (CNTs) exhibit tremendous potential in application due to superior electrical and mechanical properties, and the excellent lithium insertion properties make it possible to be LIBs anode materials. Based on the lithium insertion mechanism of CNTs, this paper systematically and categorically reviewed the design strategies of CNTs-based composites as LIBs anode materials, and summarized in detail the enhancement effect of CNTs fillers on various anode materials. More importantly, the superiorities and limitations of various anode materials for LIBs were evaluated. Finally, the research direction and current challenges of the industrial application of CNTs in LIBs were prospected.

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Heterocycles are an important class of compounds that are widely used in pharmaceuticals, agrochemicals, dyes, and materials. Multicomponent reactions (MCRs) offer efficient synthetic routes for producing these complex structures. The search for effective and sustainable catalytic processes in organic synthesis has led to the exploration of various nanomaterials as potential catalysts. To this end, carbon nanotubes (CNTs) have recently emerged as promising heterogeneous catalysts for the MCR synthesis of heterocycles due to their unique properties, which include high surface area and reactivity, tunable surface chemistry, excellent electrical conductivity, recyclability, and exceptional thermal and chemical stability. This review provides a comprehensive analysis and overview of the use of CNTs as catalysts for synthesizing heterocycles via MCRs and their advantages.

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The optimization of pellet fuels composed of rice straw, mustard straw, and sawdust was investigated in the present study to improve their properties and utility. Response surface methodology (RSM) and an artificial neural network (ANN) integrated with a multi-objective genetic algorithm (MOGA) were applied to optimize pellet composition for enhanced heating value and minimized ash, nitrogen, and sulfur content. An optimal blend of 74.40% rice straw, 15.60% mustard straw, and 10% sawdust was identified by RSM. These proportions were closely approximated by the MOGA-ANN model within ±1%, and the results were confirmed through experimental validation. Combustion ion chromatography was also used, to analyze the biomasses and the optimized blend, revealing reduced chloride (4189 mg/kg) and sulfur (2716 mg/kg) levels. These results were validated subsequently through experimental tests, confirming the accuracy of the proposed models. A techno-economic analysis indicated that a generation cost of Rs. 10.71 per unit would be associated with a fully agro-residue-based power plant, while less than Rs. 5.28–Rs. 5.31 would be the cost of generation per unit of electricity observed with 5% biomass co-firing in thermal plants. This study demonstrates that improved fuel quality and economic feasibility for biomass power generation can be achieved through strategic biomass blending and co-firing. These findings demonstrated that the blending of various biomass can be a viable strategy for enhancing the characteristics of pellet fuels on an industrial scale.

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Developing advanced anode materials is one of the effective strategies to enhance the electrochemical performance of sodium-ion batteries (SIBs). Herein, inspired by the biological central nervous system structure, we report a facile and efficient strategy to fabricate the three-dimensional hierarchical neural network-like carbon architectures, where the glucose-derived hard carbon (HC) nanospheres are in situ assembled and embedded in carbon nanotube (CNT) network nanostructure (HC/CNT hybrid networks). The HC nanospheres with large carbon interlayer spacing help to decrease the diffusion length of sodium ions and the interconnected CNT networks enable the rapid electron transfer during charge/discharge process. Benefiting from these structure merits, the as-made HC/CNT hybrid networks can deliver a superior rate capacity of 162 mA h g⁻¹ at the current density of 5 A g⁻¹. Additionally, it exhibits excellent cycling performance with a capacity retention rate of 86.3% after 140 cycles. This work offers a promising candidate anode material for SIBs and a new prospect towards carbon-based composites design, simultaneously.

Nitrite is commonly found in various aspects of daily life, but its excessive intake poses health risks like blood oxygen transport impairment and cancer risks. Accurate detection of nitrite is crucial for preventing its potential harm and ensuring public health. In this work, Cu–Co bimetallic nanoparticles (NPs) incorporated nitrogen-doped carbon dodecahedron (Cu/Co@N–C/CNTs-X, where X denotes the carbonization temperatures) are synthesized by facile carbonization of CuO@ZIF-67 composites. Cu and Co NPs are uniformly embedded in the carbon dodecahedron decorated by carbon nanotubes (CNTs) without agglomeration. Combining the superior catalytic from Cu and Co NPs with the electrical conductivity and stability from the carbon frameworks, the Cu/Co@N–C/CNTs-600 composite as catalyst detected nitrite concentrations ranging from 1 to 5000 μM, with sensitivity values of 0.708 μA μM^–1 cm^–2, and a detection limit of 0.5 μM. Moreover, this sensor demonstrated notable selectivity, stability and reproducibility. The design of Cu/Co@N–C/CNTs-X catalysts prepared in this study can be used as an attractive alternative in the fields of food quality and environmental detection.

As increasing markets for Lithium‒ion battery (LiB), several environmental issues have attained great attention. Especially, the organic solvent N‒Methyl‒2‒Pyrrolidone (NMP), commonly used in the traditional slurry casting process for fabricating LiB electrodes, will be about to be regulated due to its toxicity and the environmental concerns. Therefore, the production of LiB electrodes by a dry process without using NMP organic solvents is of special interest nowadays. In the dry process, it is generally accepted that 1‒dimensional carbon materials like carbon nanotubes (CNT) are beneficial than conventional carbon conductor such as carbon blacks (CB). However, CB is inevitably included during the CNT production, simultaneously as an impurity. Refining CNT from CNT/CB mixture can cause another cost obviously. On the other hand, there have been limited information to study dispersion of carbon materials in electrode with respect to dispersion method and types of carbon conductor. Here, we systematically test the effect of dispersibility of carbon conductor in electrode according to dispersion method and type of carbon conductors. In addition, effect of CB amount in carbon conductor are also elucidated on manufacturing procedure, properties of electrode and their electrochemical performances.

Colorectal cancer (CRC) poses a significant global public health challenge, accounting for 10% of newly diagnosed cancer cases and causing 9.4% of cancer-related deaths. Conventional treatment methods like surgery, chemotherapy, and radiation have shown limited success despite the increasing incidence of CRC. Thus, there is an urgent need for innovative therapeutic approaches. Researchers are continually working on developing novel technologies, notably focused on the creation of safe and effective cancer nanomedicines, in their continuous effort to advance cancer treatment. Nanoparticles exist at the nanoscale. Nanoparticles at the nanoscale have distinctive properties that leverage the metabolic disparities between cancerous and normal cells. This property allows them to selectively induce substantial cytotoxicity in cancer cells while minimizing damage to healthy tissue. Carbon nanomaterials (CNMs), including graphene oxide (GO), carbon nanotubes (CNTs), and nanodiamonds (NDs), have undergone extensive investigation due to their biocompatibility, surface-to-volume ratio, thermal conductivity, rigid structural properties, and ability for post-chemical modifications. Notably, GO has emerged as a promising two-dimensional (2D) material for cancer treatment. Several groundbreaking nanoparticle-based therapies, predominantly utilizing GO, are currently undergoing clinical trials, with some already gaining regulatory clearance.