Carbon Letters最新文献

{"title":"Efficient optical sensing of nitrophenol using low-rank coal-based graphene quantum dots","authors":"Archana Shau,&nbsp;Lokesh Kumar Jangir,&nbsp;Mayadhar Barik,&nbsp;Poonam Kumari","doi":"10.1007/s42823-026-01085-8","DOIUrl":"10.1007/s42823-026-01085-8","url":null,"abstract":"<div><p>Low-rank coal is typically regarded as waste or underutilized in conventional industries as an energy source. When burned, it generates elevated levels of carbon dioxide (CO₂), sulfur dioxide (SO₂), and fine particulate matter (PM), all of which contribute to global warming and climate change. In this manuscript, we explore the utilization of low-rank coal for the synthesis of graphene quantum dots (GQDs) through a straightforward and cost-effective method. The structural characteristics of the GQDs were examined using FTIR and XPS spectroscopy, while their morphology was analyzed through TEM and HR-TEM techniques. The synthesized GQDs exhibited a notable quantum yield of approximately 0.063. Optical kinetic studies demonstrated the high stability of these GQDs. Furthermore, the GQDs were employed as optical probes for the detection of 4-nitrophenol and 2,4-dinitrophenol, with a detection limit of 1.44 and 1.89 µmol L^− 1, respectively. A plausible detection mechanism for nitrophenol using GQDs is also discussed.</p><h3>Graphical Abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":506,"journal":{"name":"Carbon Letters","volume":"36 4","pages":"1711 - 1725"},"PeriodicalIF":6.2,"publicationDate":"2026-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148458686","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A sustainable and multifunctional magnetic sulfonated tragacanth–MWCNT-COOH/ZnCuFe₂O₄ nanobiocatalyst for the efficient synthesis of bioactive polyhydroquinolines","authors":"Shefa Mirani Nezhad,&nbsp;Armin Rahmavand,&nbsp;Ehsan Nazarzadeh Zare,&nbsp;Seied Ali Pourmousavi,&nbsp;Alireza Ashrafi Fashi,&nbsp;Soran Ghadermazi,&nbsp;Saba Fakhlaee,&nbsp;Taotao Zhao","doi":"10.1007/s42823-026-01089-4","DOIUrl":"10.1007/s42823-026-01089-4","url":null,"abstract":"<div><p>The development of efficient heterogeneous catalysts plays a crucial role in facilitating sustainable and high-yield organic syntheses. In this study, a multifunctional nanocomposite based on sulfonated tragacanth, carboxylated multi-walled carbon nanotubes, and ZnCuFe₂O₄ nanoparticles (STrag/MWCNT-COOH/ZnCuFe₂O₄) was designed and synthesized. The fabrication involved a modified sol–gel synthesis of ferrite nanoparticles, chemical functionalization of tragacanth and MWCNTs, and subsequent integration into a hybrid composite. Characterization using field emission scanning electron microscopy (FESEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET), energy-dispersive X-ray spectroscopy (EDX), elemental mapping, and vibrating sample magnetometry (VSM) confirmed the formation of a well-dispersed, porous, and magnetically responsive nanocomposite. The material demonstrated excellent catalytic efficiency in the one-pot synthesis of diverse polyhydroquinolines under mild reflux conditions, providing high yields (87–95%) in short reaction times (35–70 min). The resulting polyhydroquinolines exhibited antioxidant activity (DPPH scavenging up to 79.4%) and antibacterial activity (inhibition zones of 8–14 mm). Furthermore, the nanocomposite maintained its catalytic performance over multiple reuse cycles, highlighting its potential as a versatile platform for environmentally friendly catalysis and bioactive molecule development.</p><h3>Graphical abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":506,"journal":{"name":"Carbon Letters","volume":"36 4","pages":"1767 - 1791"},"PeriodicalIF":6.2,"publicationDate":"2026-06-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148458952","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Thermal pathway engineering in epoxy molding compounds via high-loading SiO2-embedded carbon nanofibers fabricated by syringeless electrospinning","authors":"Suk Jekal,&nbsp;Yoon-Ho Ra,&nbsp;Jiwon Kim,&nbsp;Woohyeon Kim,&nbsp;Jeongsu Kim,&nbsp;Jinseo Park,&nbsp;Sae Hee Kim,&nbsp;Su Been Kim,&nbsp;Soong-Keun Hyun,&nbsp;Chang-Min Yoon","doi":"10.1007/s42823-026-01090-x","DOIUrl":"10.1007/s42823-026-01090-x","url":null,"abstract":"<div><p>In this study, carbon nanofibers (CNFs) with high SiO₂ loading are developed as thermally conductive additives for epoxy molding compounds (EMCs) used in advanced semiconductor packaging. A syringeless electrospinning strategy is employed to fabricate high-content SiO₂-embedded CNFs, while interfacial engineering of SiO₂ <i>via</i> silane treatment is introduced to control precursor-stage rheological behavior. Specifically, amine-functionalized SiO₂-embedded CNFs exhibit the highest increase in precursor viscosity due to enhanced polymer–particle interactions, allowing uniform SiO₂ embedding along the CNF backbone at an optimal loading amount of 20 wt%. When incorporated into EMC at 0.6 wt%, the additive exhibits the highest mechanical strength and thermal conductivity enhancement. The superior performance originates from the synergistic contributioon of continuous heat-dissipation pathways provided by the carbon framework and the optimized packing factor achieved by SiO₂ embedding. Infrared thermography further confirms enhanced heat transport, showing a 9.4 °C higher surface temperature compared with pristine EMC after 3 min of heating. These findings highlight that the structural evolution of CNFs with embedded inorganic fillers, combined with precursor-stage interfacial and rheological engineering, provides a new design strategy of carbonaceous material for thermally and mechanically stable EMC systems.</p></div>","PeriodicalId":506,"journal":{"name":"Carbon Letters","volume":"36 4","pages":"1793 - 1807"},"PeriodicalIF":6.2,"publicationDate":"2026-06-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148459025","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimisation lignin core-shell structures for sodium-ion batteries","authors":"Judith Miralda-Jalle,&nbsp;Mario Culebras,&nbsp;Tadhg Kennedy,&nbsp;Maurice N. Collins","doi":"10.1007/s42823-026-01087-6","DOIUrl":"10.1007/s42823-026-01087-6","url":null,"abstract":"<div><p>Sodium-ion batteries (SIBs) are a sustainable alternative to lithium systems due to the abundance and low cost of sodium. Hard carbon is the most promising SIB anode material. Here, lignin, an abundant aromatic by-product, was used as a renewable carbon precursor to fabricate core–shell nanofibers via coaxial electrospinning. The baseline sample (CS-3.00) exhibited partial shell collapse due to insufficient interfacial consolidation before stabilisation. To address this, a solvent-mediated post-spinning treatment was introduced by immersing the as-spun fibers in hexane for 5–10 min before thermal processing, influencing pore evolution during carbonisation and sodium storage behaviour. The optimised sample showed a 129% increase in specific capacity compared to the standard one.</p><h3>Graphical abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":506,"journal":{"name":"Carbon Letters","volume":"36 4","pages":"1741 - 1747"},"PeriodicalIF":6.2,"publicationDate":"2026-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s42823-026-01087-6.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148458871","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of micropore size of activated carbon fibers prepared by steam activation on toluene adsorption","authors":"Hae-Reum Shin,&nbsp;Dong-Jun Kwon,&nbsp;Man-Tae Kim","doi":"10.1007/s42823-026-01081-y","DOIUrl":"10.1007/s42823-026-01081-y","url":null,"abstract":"<div><p>Activated carbon fibers (ACFs) are highly effective adsorbents for gas separation, water purification, and hazardous gas removal owing to their substantial specific surface area and adjustable pore structure. This study investigated how the pore size of ACFs influenced the adsorption of toluene, a volatile organic compound (VOC). To modulate the pore size, ACFs were synthesized at various steam flow rates during steam activation. All samples demonstrated adsorption efficiencies exceeding 99%, with a maximum capacity of 0.418 g/g, but micropores within the 0.65 to 0.85 nm range proved most effective. Among the samples, ACF0.8 showed the highest adsorption capacity and the longest breakthrough time. Correlation analysis revealed a positive trend between toluene uptake and total ultramicropore volume (R² = 0.84), whereas the 0.65–0.85 nm pore range exhibited a significantly closer association with adsorption capacity (R² = 0.98). These results indicate that controlling the steam flow is a viable strategy for optimizing micropore characteristics, offering practical design guidelines for the development of high-performance ACF-based VOC adsorbents.</p></div>","PeriodicalId":506,"journal":{"name":"Carbon Letters","volume":"36 4","pages":"1655 - 1665"},"PeriodicalIF":6.2,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148458734","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tuning interfacial charge dynamics in 2D SnO2–MWCNT composite photoanodes for dye-sensitized solar cells","authors":"Rohan B. Ambade,&nbsp;Sambhaji S. Bhande,&nbsp;Yahya Zweiri,&nbsp;Rajaram S. Mane,&nbsp;Swapnil B. Ambade","doi":"10.1007/s42823-026-01080-z","DOIUrl":"10.1007/s42823-026-01080-z","url":null,"abstract":"<div><p>This paper presents a low-temperature, facile, and cost-effective wet chemical synthesis of two-dimensional (2D) tin oxide (SnO₂)–multi-walled carbon nanotube (MWCNT) composites for efficient dye-sensitized solar cells (DSSCs). Incorporating varying concentrations of MWCNTs into 2D SnO₂ nanosheets significantly enhanced the overall photovoltaic performance by improving charge separation and suppressing electron–hole recombination. The 2D SnO₂–MWCNT composites exhibited remarkable photoluminescence quenching and increased UV-vis absorbance, indicating efficient photoinduced charge transfer. The optimized 2D SnO₂–MWCNT composite photoanode achieved a power conversion efficiency (PCE) of 3.84%, which was ~ 3.5 times higher than that of the pristine SnO₂ nanosheets (1.83%). This PCE improvement was attributed to an increase in the short-circuit current density (<i>J</i>_<i>sc</i>) and the fill factor (<i>FF</i>). Additionally, electrochemical impedance spectroscopy (EIS) measurements confirmed the reduced charge transport resistance, increased electron diffusion length, enhanced charge collection efficiency, and enhanced electron mobility of the 2D SnO₂–MWCNT composites. This improved photovoltaic performance is primarily attributed to the incorporation of MWCNTs, which provide efficient electron-conducting pathways that mitigate recombination. These results highlight the potential of 2D SnO₂–MWCNT composites as efficient photoanodes for DSSCs, providing valuable insights into the interfacial charge dynamics of next-generation optoelectronic devices.</p></div>","PeriodicalId":506,"journal":{"name":"Carbon Letters","volume":"36 4","pages":"1643 - 1654"},"PeriodicalIF":6.2,"publicationDate":"2026-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s42823-026-01080-z.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148458852","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Machine learning prediction of CO₂ solubility in deep eutectic solvent-MDEA mixtures","authors":"Amir Hossein Sheikhshoaei,&nbsp;Ali Sanati","doi":"10.1007/s42823-026-01082-x","DOIUrl":"10.1007/s42823-026-01082-x","url":null,"abstract":"<div><p>This study introduces machine learning (ML) models to predict CO₂ solubility in mixtures of a deep eutectic solvent (tetrabutylammonium bromide: ethylene glycol, 1:4 molar ratio) and methyldiethanolamine (MDEA). To ensure robust extrapolation capabilities and prevent potential data leakage, a rigorous grouped validation strategy, known as “Leave-One-Composition-Out,” was implemented, replacing conventional random data splitting. Four ML algorithms, Gradient Boosting (GBoost), Gaussian Process Regression (GPR), AdaBoost-SVR, and Multilayer Perceptron (MLP), were evaluated using temperature, pressure, and MDEA weight% as input features. Results revealed that the GPR model outperformed all others across all statistical metrics, achieving an <span>({R}^{2})</span> value of 0.996 and a mean absolute error (MAE) of 0.2839%. Furthermore, SHAP (SHapley Additive exPlanations) analysis identified pressure as the most significant driving factor for CO₂ solubility, while temperature exhibited an inverse correlation. Crucially, this perfect alignment with fundamental principles clearly demonstrates that the model successfully learned the underlying thermodynamic relationships rather than merely memorizing numerical data. Finally, leverage validation confirmed that 99.16% of the data points safely reside within the model’s valid applicability domain. This work establishes the developed GPR framework as a highly reliable and physically consistent approach for predicting CO₂ solubility and optimizing complex multi-component capture systems.</p></div>","PeriodicalId":506,"journal":{"name":"Carbon Letters","volume":"36 4","pages":"1667 - 1679"},"PeriodicalIF":6.2,"publicationDate":"2026-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148458667","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dual-function phosphoric acid strategy for synthesis of 3D cage-structured mesoporous carbons with tunable pore/window architectures toward high-performance lithium–sulfur batteries","authors":"Sun Hyu Kim,&nbsp;Je Yeon Kim,&nbsp;Hyung Ik Lee,&nbsp;Yongwoo Lee,&nbsp;Hye Ran Kim,&nbsp;Kyoung Mun Kim,&nbsp;Seok Kim,&nbsp;Yongju Jung","doi":"10.1007/s42823-026-01083-w","DOIUrl":"10.1007/s42823-026-01083-w","url":null,"abstract":"<div><p>A new synthesis route for three-dimensional cage-type mesoporous carbon was developed using phosphoric acid (H₃PO₄) as a dual-function catalyst. H₃PO₄ promoted dehydration of sucrose as an acid catalyst and enabled systematic tuning of both cage size and inter-cage window size by forming a polyphosphoric acid layer at the silica–carbon interface. By increasing the H₃PO₄/sucrose molar ratio, uniform mesopore diameters expanded from 13.1 to 16.6 nm and window sizes from 7.3 to 9.8 nm at a pyrolysis temperature of 900 °C. In lithium-sulfur (Li–S) batteries, enlarged windows significantly improved lithium polysulfides (LiPSs) transport and rate capability. Notably, a well-preserved, template-replicated mesoporous framework was achieved even at an exceptionally low carbonization temperature of 400 °C, whereas sulfuric-acid-derived samples exhibited poorly developed porosity and structural collapse under identical conditions. The cage-type mesoporous carbon synthesized at 400 °C retained abundant oxygen- and phosphorus-containing polar functional groups, as confirmed by elemental analysis and XPS, leading to markedly enhanced LiPSs adsorption. Accordingly, the highly functionalized mesoporous carbon delivered superior cycling stability, maintaining 82.3% of its initial capacity after 300 cycles. Post-mortem XPS analysis further confirmed strong chemical interactions between LiPSs and surface functional groups. Importantly, H₃PO₄ played a dual role as an acid catalyst and pore-structure modifier by forming a polyphosphoric acid layer at the silica–carbon interface. This layer stabilized the carbon precursor via strong polar–polar interactions, effectively suppressing pore collapse and mesopore merging. Such interfacial stabilization can provide a general strategy for the low-temperature fabrication of structurally robust mesoporous carbons.</p></div>","PeriodicalId":506,"journal":{"name":"Carbon Letters","volume":"36 4","pages":"1681 - 1693"},"PeriodicalIF":6.2,"publicationDate":"2026-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148459000","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cashew Nut Shell–derived activated carbon/MWCNTs composite electrodes for enhanced Supercapacitor performance","authors":"Nivetha Rajendran,&nbsp;Velmathi Guruviah","doi":"10.1007/s42823-026-01078-7","DOIUrl":"10.1007/s42823-026-01078-7","url":null,"abstract":"<div><p>Supercapacitors (SCs) are one of the sophisticated energy storage devices because of their high capacitance, power density, and extended cycle life. In contrast to conventional batteries, Supercapacitors store energy electrostatically, allowing millions of operation cycles. Activated carbons (AC) made from biomass can be designed to have a hierarchical pore structure and a high specific surface area. These parameters create enormous sites for ion adsorption for SCs to store energy. In the present work, the Activated carbon was made from the Cashew Nut Shell (CNS) through chemical activation (KOH) process, and the composites (MWCNTs) with various concentrations (0wt%, 1wt%, 3wt%, 5wt%, 10wt%) were merged with the AC for making supercapacitor electrodes. From the above, the sample CM–2 (3wt% of MWCNTs + AC) exhibits a high specific surface area (1160.4 m²/g), which shows a high specific capacity of 82.5 F/g at a current of 1 mA in a two–electrode system. Moreover, it displays a maximum specific energy density of 27.8Wh kg^–1 at a specific power density of 808.4 W kg^–1. Furthermore, the fabricated coin cell for the sample CM–2 exhibited a capacitance retention of 95.58% even after the 10,000 charge–discharge cycles. Thus, the optimal wt% of MWCNTs with the AC is considered as a suitable and effective electrode for the Supercapacitor applications.</p></div>","PeriodicalId":506,"journal":{"name":"Carbon Letters","volume":"36 4","pages":"1615 - 1628"},"PeriodicalIF":6.2,"publicationDate":"2026-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148458841","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comprehensive review: challenges, strategies, and prospects of brazing fillers for joining carbon-carbon composites with self and other materials","authors":"V. Vignesh,&nbsp;Sudheer Reddy Beyanagari,&nbsp;R. Vaira Vignesh,&nbsp;M. Govindaraju","doi":"10.1007/s42823-026-01076-9","DOIUrl":"10.1007/s42823-026-01076-9","url":null,"abstract":"<div><p>Carbon-Carbon (C_f-C) composites are widely used in aerospace and nuclear applications due to their low density, excellent thermal stability, and superior mechanical properties. However, joining C_f-C to metals, ceramics, or itself remains challenging due to poor wettability and a large coefficient of thermal expansion (CTE) mismatch, leading to residual stresses, interfacial reactions, and joint degradation. Brazing has emerged as a promising solution with the use of active filler alloys. This review compares different filler systems based on wettability and performance. Al, Ag, and Cu-based fillers provide moderate joint strength (~ 20–50 MPa) but are suitable for lower-temperature applications. In contrast, Ni and Ti-based fillers provide higher strength (~ 50–70 MPa) and improved thermal performance (up to ~ 900 °C), although residual stresses and interfacial brittleness remain key challenges. In addition, recent approaches, such as particle-reinforced fillers and interlayer coatings, have shown potential in reducing residual stresses and improving joint reliability. This review highlights the relationships between filler composition, microstructure, wettability, and mechanical performance, and outlines current limitations and future directions for developing advanced brazing fillers for C_f-C composite joining.</p><h3>Graphical Abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":506,"journal":{"name":"Carbon Letters","volume":"36 4","pages":"1583 - 1614"},"PeriodicalIF":6.2,"publicationDate":"2026-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148459165","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}