Carbon Letters最新文献

LTO is a commercial anode material that contributes to delivered energy and cycle stability. With affordability and high energy density, graphite faces limited cycle time and inferior stability. Here, we discussed the LTO challenges and compared the Ti-based anode from the original structure to the LTO-MXene composites, which are promising alternative anodes. Spinel lithium titanate (LTO) possesses high working voltage, stability, safety, and negligible volume change, while it suffers from low electronic conductivity that limits rate performance at large current densities. 2D Mxenes have recently drawn attention to various applications due to high conductivity, large surface area, flexibility, and polar surface benefits. We critically reviewed the synthesis approaches, morphology views, and electrochemical behavior of LTO-MXene as new anode materials in lithium-ion batteries (LIBs). There are few reports on LTO-MXene anodes in LIBs. They provide a synergistic action of LTO and MXene, enhancing the accessibility of electrolytes and reducing the distance, benefiting fast diffusion. This review paper sheds light on how the synthesis approaches can directly affect LIB configurations' durability and energy density and lead researchers to develop features of LTO anodes with promising engagement.

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Industrialization and increasing consumerism have driven up energy demand and fossil fuel consumption, significantly contributing to global climate change and environmental pollution. While renewable energy sources are sustainable, their intermittent nature necessitates the development of efficient energy storage devices to ensure uninterrupted power supply and optimal energy utilization. Electrochemical energy storage devices are promising for sustainable energy. Traditionally, carbon electrode materials for these devices come from non-renewable sources. However, using biomass and biomass–coal blends can help substitute fossil fuels, reducing environmental impact. Recent advancements in carbon materials have achieved specific surface areas of over 2500 m²/g, resulting in supercapacitor capacitances of 250–350 F/g and cycling stability exceeding 10,000 cycles with < 5% capacity loss. In lithium-ion batteries, biomass-based anodes deliver 400–600 mA h/g, outperforming graphite. Doped carbon materials enhance charge-transfer efficiency by 20–30%, while CO₂ emissions from production are reduced by 40–60%. With 50–70% lower costs than fossil-based alternatives, biomass-derived carbons present a viable pathway for scalable, eco-friendly energy storage solutions, accelerating the transition toward sustainable energy systems. Overall, this work highlights the influence of carbon materials on the electrochemical properties and hydrogen storage capacity of biomass-based carbon materials. This also underscores their potential application in energy storage.

Electrochemical reduction of carbon dioxide is a crucial energy conversion protocol involving two significant processes: converting CO₂, a greenhouse gas, into value-added products and reducing fossil fuel usage to produce fuels or chemical products. Moreover, the production of CO from the carbon dioxide reduction reaction is highly substantial since it is a two-proton/electron reaction, and it also finds potential applications in chemical, metallurgical, and pharmaceutical industries. Among the various classes of electrocatalytic materials, single-atom catalysts have attracted great attention because of their high atom utilization. Here, we survey the recent research trends involved in the preparation of single atom-based electrocatalysts for the generation of carbon monoxide from the electroreduction of carbon dioxide.

The synthesis of functional carbon materials with controllable morphology and structure using a simple, effective, and green process starting from biomass has been an attractive and challenging topic in recent years. After decades of technological development, high value-added biomass-derived carbon nanomaterials with different morphologies and structures prepared by low-temperature hydrothermal carbonization (HTC) have been gradually developed into a huge system covering different series in different dimensions, and are widely used in the fields of adsorption, electrochemical energy storage, and catalysis. However, due to a vague understanding of the fundamental structure–performance correlation and the absence of customized material design strategies, the diverse needs in practical applications cannot be well met. Herein, we reviewed the mechanism, modifications, and applications of the low-temperature HTC method for biomass. The synthesis mechanisms, structural designs strategies, and related applications of biomass-derived hydrochar are highlighted and summarized in different dimensions, including six major categories: zero-dimensional spherical structure, one-dimensional fibrous and tubular structure, two-dimensional lamellar structure, three-dimensional hierarchical porous structure, and special-shaped asymmetric structure. Then a sustainability assessment is conducted on the hydrothermal carbonization process. Finally, the controllable preparation of biomass-derived hydrochar is summarized and prospected for the application requirements in different fields.

Microalgae, such as Chlorella vulgaris and Scenedesmus obliquus, are highly efficient at capturing carbon dioxide through photosynthesis, converting it into valuable biomass. This biomass can be further processed into carbon materials with applications in various fields, including water treatment. The reinforcement learning (RL) method was used to dynamically optimize environmental conditions for microalgae growth, improving the efficiency of biodiesel production. The contributions of this study include demonstrating the effectiveness of RL in optimizing biological systems, highlighting the potential of microalgae-derived materials in various industrial applications, and showcasing the integration of renewable energy technologies to enhance sustainability. The study demonstrated that Chlorella vulgaris and Scenedesmus obliquus, cultivated under controlled conditions, significantly improved absorption rates by 50% and 80%, respectively, showcasing their potential in residential heating systems. Post-cultivation, the extracted lipids were effectively utilized for biodiesel production. The RL models achieved high predictive accuracy, with R² values of 0.98 for temperature and 0.95 for oxygen levels, confirming their effectiveness in system regulation. The development of activated carbon from microalgae biomass also highlighted its utility in removing heavy metals and dyes from water, proving its efficacy and stability, thus enhancing the sustainability of environmental management. This study underscores the successful integration of advanced machine learning with biological processes to optimize microalgae cultivation and develop practical byproducts for ecological applications.

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Due to the sturdy photoluminescence and absorption, CQDs emerged as a suitable candidate for optical sensing probe. The present study deals with the synthesis of blue-fluorescent Carbon Quantum Dot (TAA-CQD) using tannic acid and glycine as novel precursors. The TAA-CQD were synthesised hydrothermally with the high production yield and QY to be 86.12 and 21%, respectively, and an average particle size of 1.9 nm. The TAA-CQD aqueous solution displays excitation-dependent fluorescence emission in the excited range from 420 to 650 nm. The CIE co-ordinates in a highly blue region at (0.14, 0.19) confirmed the synthesised TAA-CQD were blue in fluorescent. Fluorescence of TAA-CQD was stable under all pH range, resisted the high ionic strengths condition and stable over 8 months. Furthermore, the fluorescent TAA-CQD was capable in detecting a tetracycline-classed antibiotic Doxycycline (DXY) along with remarkable selectivity and sensitivity. The measures limit of detection (LOD) was very low 2.42 mM in comparison to other methods. Moreover, the applicability of the proposed work has been fruitfully employed on the pharmaceutical waste. Thus, our designed TAA-CQD based fluorescence sensing system hold great promise for the advanced sensing materials in the detection of DXY and we believe that our approach will be promising and viable in a clinical applications.

The accurate detection of vital biomarkers such as Ascorbic Acid (AA), Uric Acid (UA) and Nitrite (NO₂⁻) is crucial for human health surveillance. However, existing methods often struggle with concurrent detection and quantification of multiple species, highlighting the need for a more effective solution. To address this challenge, this study aimed to develop a multifunctional electrochemical sensor capable of parallel detection of AA, UA and NO₂⁻ using a synergistic combination of Graphene Oxide (GO) and Cadmium Sulfide (CdS) materials. Notably, the fabricated CdS@GO/Glassy Carbon Electrode (GCE) exhibited exceptional electrochemical activity, as evidenced by Differential Pulse Voltammetry (DPV) analysis. The sensor demonstrated remarkable sensitivity (8.13, 10.12, and 9.05 μA·μM⁻¹·cm⁻²) and ultra-low detection limits (0.034, 0.062, and 0.084 µM) for AA, UA and NO₂⁻, respectively. Furthermore, it successfully identified single molecules of each analyte in aqueous and biologic fluid samples, with recovery values comparable to those obtained using High-Performance Liquid Chromatography (HPLC) standard addition methods. The significance of this study lies in developing a novel CdS@GO/GCE sensor that enables concurrent detection and quantification of multiple vital biomarkers, offering a promising tool for human health monitoring and diagnosis.

Mesoporous carbon microspheres (CMs) have recently received much attention by virtue of their large pore size; open framework structure, high surface area, and idiosyncratic spherical nature, which contribute to chemical stability and electrical and thermal conductivity. The inherent difficulties of these materials can be reduced by surface modification techniques, resulting in a new system with ameliorated properties. Like other carbonaceous materials, CMs also have the upper hand in controlling composites’ physicochemical and morphological behaviours because of their carefully controlled size, thickness, surface properties, etc. We can explore the possibilities of these properties by fabricating supercapacitors, sensors, batteries, separation membranes, etc. The key focus of our review is to summarise the various synthetic protocols adopted for composite preparation, the difficulties, and the advantages of the method. In addition, we have tried to incorporate multiple applications and future perspectives of CM-based composites.

The development of hydrogen energy is crucial for achieving global dual-carbon strategic goals, namely "carbon peak" and "carbon neutrality." Photocatalytic water splitting, powered by solar energy, presents a promising approach to hydrogen production. Advancing this technology requires the development of photocatalysts that are cost-effective, highly active, and stable. As a non-metallic semiconductor, g-C₃N₄ stands out for its potential in sustainable energy and environmental remediation technologies, garnering considerable interest for its efficiency in harnessing light-driven reactions. Although g-C₃N₄ exhibits promising characteristics, its practical application is significantly hindered by the rapid recombination of photogenerated charge carriers and its limited light absorption range. This review highlights various strategies employed to improve the photocatalytic hydrogen production efficiency of g-C₃N₄, including heteroatom doping, microstructure control, co-catalyst modification, defect engineering, and heterojunction construction. These strategies enhance active site density, light absorption capacity, and photogenerated charge separation in g-C₃N₄, thereby boosting electron migration rates and improving photocatalytic hydrogen production. Additionally, we explore the potential of integrating cutting-edge AI technology with advanced instrumentation for the prediction, design, preparation, and in-situ characterization of g-C₃N₄-based photocatalytic systems. This review aims to offer key insights into the design, development, and practical application of innovative, high-performance carbon-based catalysts.

To further increase the mechanical properties of polyacrylonitrile-based carbon fibers, a multiple stretching technique was applied. Carbon fibers were multiple stretched at 2200 °C and characterizations such as SEM, Raman, XRD, and TEM were used to investigate the evolution of microstructure of carbon fibers. It was found that the grooves on the surface of carbon fibers along the fiber axis direction became more obvious and the cross-section of fibers were twisted from nearly circular to elliptical after multiple stretching. Growth and slippage of graphite microcrystals along the fiber axis direction resulted decrease in disordered structure and defects in the carbon fibers and increase in the degree of graphitization. The multiple stretching effectively enhanced the length-to-width ratio of microcrystals. An increase of 75 GPa in tensile modulus and a retention rate of 0.95 in tensile strength were realized for carbon fibers multiple stretched at 2200 °C.