Diamond and Related Materials最新文献

{"title":"Hydrazine nitridation of oxidized or non-oxidized twisted multilayer graphene","authors":"Nikita D. Mitiushev ,&nbsp;Oleg V. Kononenko ,&nbsp;Alexander V. Zotov ,&nbsp;Anatoliy A. Firsov ,&nbsp;Evgeny N. Kabachkov ,&nbsp;Victor N. Matveev ,&nbsp;Andrei N. Baranov","doi":"10.1016/j.diamond.2025.112881","DOIUrl":"10.1016/j.diamond.2025.112881","url":null,"abstract":"<div><div>Twisted multilayer graphene films were synthesized using chemical vapor deposition. The films were treated in oxygen plasma and reduced with hydrazine in the vapor phase to replace inserted oxygen groups with nitrogen ones. Some of the films were treated by hydrazine without preliminary oxidation. The processes of graphene oxidation, reduction and nitridation were characterized using scanning electron microscopy and Raman spectroscopy. Changes in the chemical composition after nitriding of synthesized or oxidized graphene were determined using x-ray photoelectron spectroscopy (XPS). Electrical transport properties of the multilayer graphene films were measured using the Hall and magnetoresistive effect. It was found that pre-oxidation of the film before nitridization makes it possible to increase the amount of graphitized nitrogen, which is a strong donor impurity, by 1.5 times. This leads to a decrease in the concentration of positively charged carriers by more than two times and an increase in the film resistance by more than three times.</div></div>","PeriodicalId":11266,"journal":{"name":"Diamond and Related Materials","volume":"159 ","pages":"Article 112881"},"PeriodicalIF":5.1,"publicationDate":"2025-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145154454","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":"Lanthanide-doped diamond: Electronic properties and magnetic analysis","authors":"Yu-Tao Yang ,&nbsp;Wen-Dan Wang ,&nbsp;Ting-Ting Tan ,&nbsp;Dong-Sheng Li ,&nbsp;Qi-Jun Liu","doi":"10.1016/j.diamond.2025.112865","DOIUrl":"10.1016/j.diamond.2025.112865","url":null,"abstract":"<div><div>Diamond exhibits unique potential for stabilization of spin ordering due to its exceptionally small lattice constant (3.57 Å), providing an ideal platform for developing high-temperature resistant and radiation-tolerant spintronic devices. However, most transition element-doped diamond systems suffer from insufficient or negligible magnetic moments. The distinctive electronic configuration of lanthanide elements endows them with exceptional magnetic properties. Therefore, incorporating lanthanide atoms into diamond could effectively regulate the magnetic exchange interactions while achieving carrier spin polarization through 4f-2p orbital hybridization. This study systematically investigates the electronic structure characteristics, magnetic moment distribution, and magnetic coupling properties of eight lanthanide-doped diamond systems (Nd, Pm, Sm, Gd, Dy, Ho, Tm, and Lu). Results reveal that the defect formation energy decreases progressively with increasing 4f electron count, showing lower values than those of transition element-doped systems (Ti/S/Se/Ni/Co), thereby confirming their superior thermodynamic stability. Charge transfer from lanthanide atoms to carbon atoms occurs during doping. Except for Lu (with fully occupied 4f orbitals), all doped systems exhibit magnetic characteristics. Notably, Nd/Sm-doped structures demonstrate metallic behavior in spin-up channels and semiconducting properties in spin-down channels, achieving 100% spin polarization at the Fermi level. Magnetic calculations confirm the magnetic stability of Nd/Sm/Pm/Gd/Dy/Ho/Tm-doped systems with total magnetic moments of 4.00μ_B, 6.00μ_B, 3.00μ_B, 7.95μ_B, 6.00μ_B, and 4.99μ_B, respectively. Spin polarization analysis indicates that Nd/Sm-doped systems exhibit superior spin injection efficiency than Pm/Gd/Dy/Ho/Tm-doped counterparts. Through comprehensive analysis of electronic structures, magnetic moment distributions, and coupling characteristics, this work elucidates the electronic properties and magnetic regulation mechanisms in lanthanide-doped diamond systems, providing theoretical guidance for designing diamond-based diluted magnetic semiconductor materials.</div></div>","PeriodicalId":11266,"journal":{"name":"Diamond and Related Materials","volume":"159 ","pages":"Article 112865"},"PeriodicalIF":5.1,"publicationDate":"2025-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145154447","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":"Effect of calcination temperatures on γ-graphyne for simultaneous electrochemical detection of dopamine, uric acid, and ascorbic acid","authors":"Pei-Wei Chen ,&nbsp;Mei-I Wu ,&nbsp;Yan-Hua Chen ,&nbsp;Min-Jun Wu ,&nbsp;Han-Wei Chang ,&nbsp;Yu-Chen Tsai","doi":"10.1016/j.diamond.2025.112872","DOIUrl":"10.1016/j.diamond.2025.112872","url":null,"abstract":"<div><div>Given the increasing public concern over health-related issues, multiplexed detection of biomarkers has become essential in biomedical diagnostics. In this study, we developed a novel electrochemical sensor based on calcined γ-graphyne (γ-GYN). The material was synthesized by first preparing γ-graphyne (γ-GY) through an ultrasonic sonochemical method and subsequently calcined at various temperatures to obtain γ-GYN. The calcination process introduces structural imperfections and open edges, transforming γ-graphyne (γ-GY) into a more defect-rich γ-GYN with enhanced electrochemical properties. This modified structure facilitates the simultaneous electrochemical detection of ascorbic acid (AA), dopamine (DA), and uric acid (UA).</div><div>The physicochemical properties of γ-GY and γ-GYN materials were systematically characterized using scanning electron microscopy (SEM), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). Electrochemical performance was evaluated through cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The γ-GYN modified electrodes demonstrated outstanding sensing performance due to their optimized structural characteristics, featuring a loosely stacked layered structure and increased exposure of active sites. The sensor enabled simultaneous detection of AA, DA, and UA with linear ranges of 200–1000, 0.6–2.0, and 10–1000 μM, respectively. The corresponding detection limits were 36.87 μM for AA, 0.09 μM for DA, and 0.85 μM for UA, with sensitivities of 0.68, 220.49, and 12.77 μA μM⁻¹ cm⁻², respectively. These findings not only confirm the excellent performance of γ-GYN-based materials but also establish γ-GYN as a promising platform for electrochemical multi-analyte detection. The integration of γ-GYN into such detection systems opens a new pathway for developing diagnostic tools that are low-cost, portable, and highly sensitive, thereby improving healthcare delivery and reducing healthcare costs associated with managing community health conditions.</div></div>","PeriodicalId":11266,"journal":{"name":"Diamond and Related Materials","volume":"159 ","pages":"Article 112872"},"PeriodicalIF":5.1,"publicationDate":"2025-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145154387","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":"Microstructure and friction-enhancing properties of electroless Ni-P/diamond composite coating with high bonding strength of diamond particles","authors":"Yu-duo Ma ,&nbsp;Tong-wang Liu ,&nbsp;Hao Yin ,&nbsp;Guo-qiang Lv ,&nbsp;Yong Yang ,&nbsp;Peng-yue Gao ,&nbsp;Sheng-li Li ,&nbsp;Peng-long Nie ,&nbsp;Tao Feng ,&nbsp;Zhen-xiao Li ,&nbsp;Ming-fei Kuang ,&nbsp;Jian-feng Wei ,&nbsp;Li Jiao ,&nbsp;Chun-yan Wang ,&nbsp;Li-qiang Zhang","doi":"10.1016/j.diamond.2025.112871","DOIUrl":"10.1016/j.diamond.2025.112871","url":null,"abstract":"<div><div>The friction-enhancing performance of Ni-P/diamond composite coating critically depends on diamond particle bonding strength and uniform distribution. Herein, a metastable Ni-P/diamond coating featuring high bond strength and uniform diamond distribution was successfully developed. The current study reveals the regulation of the bond strength and distribution density of diamond particles in Ni-P/diamond composite coating, as well as the regulation of the microstructure and properties of the composite coating. The main phases of the metastable Ni-P/diamond composite coating were amorphous, diamond and Ni. The Ni-P/diamond composite coating has diamond particles embedded in a size of 1/2–2/3 of their particle size, and the surface distribution density of diamond particles was 25 %. The static coefficient of friction of the Ni-P/diamond composite coating was 0.58. The as-prepared friction-enhancing spacer samples were run in a 560 kW engine for 500 h and no delamination of diamond particles from the Ni-P/diamond composite coating was observed.</div></div>","PeriodicalId":11266,"journal":{"name":"Diamond and Related Materials","volume":"159 ","pages":"Article 112871"},"PeriodicalIF":5.1,"publicationDate":"2025-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145154357","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":"Sustainable sulfur hosts from durian shells-derived porous carbon for enhanced cycling stability in lithium‑sulfur batteries","authors":"Sukanya Pothaya,&nbsp;Nattida Maeboonruan,&nbsp;Jaruwit Lohitkarn,&nbsp;Chatwarin Poochai,&nbsp;Yaowamarn Chuminjak,&nbsp;Chakrit Sriprachuabwonga","doi":"10.1016/j.diamond.2025.112879","DOIUrl":"10.1016/j.diamond.2025.112879","url":null,"abstract":"<div><div>This study investigates the impact of porous carbon derived from waste durian shells on the performance of electrochemical lithium‑sulfur (Li<img>S) batteries. Two different preparation methods were employed to synthesize porous carbon: a one-step KOH activation via hydrothermal carbonization (PDR<img>H) and a two-step process involving biochar activation followed by carbonization (PDR<img>B). The synthesized porous carbons were characterized using BET, SEM, TEM, XRD, Raman, and TGA to determine their chemical and physical properties. Despite similar surface areas, the two samples exhibited different pore volumes and pore size distributions. PDR-B primarily displayed mesopores (2–30 nm) after activation, whereas PDR-H showed a combination of micro/mesopores (1.5–8 nm). PDR/S composites were prepared by melt-diffusion method with a 7:3 mass ratio of sulfur to carbon. Electrochemical performance testing indicated that the PDR-H/S composite exhibited superior cycling stability, retaining 50 % of its capacity after 400 cycles at 0.2C, and delivered a higher discharge capacity of 583.7 mAhg⁻¹ at 0.1C compared to the PDR-B/S composite, which achieved 477 mAhg⁻¹.The improved long-term cycling stability of PDR-H/S is attributed to better sulfur confinement within its varied pore structure (micro/mesopores). The presence micro/mesopores in PDR-H appears to be more effective for sulfur confinement and thus leads to better battery performance. Additionally, the study highlights that, beyond surface area and pore volume, the pore size distribution plays a crucial role in determining the electrochemical performance of the PDR/S composites.</div></div>","PeriodicalId":11266,"journal":{"name":"Diamond and Related Materials","volume":"159 ","pages":"Article 112879"},"PeriodicalIF":5.1,"publicationDate":"2025-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145154386","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":"Phonon thermal transport in diamond-graphene superlattices","authors":"Zeyu Guo,&nbsp;Guanting Li,&nbsp;Mingyue Lv,&nbsp;Jing Wan","doi":"10.1016/j.diamond.2025.112880","DOIUrl":"10.1016/j.diamond.2025.112880","url":null,"abstract":"<div><div>Diamond-graphene superlattices, constructed by periodically assembling diamond and graphene domains via strong covalent bonds, have attracted increasing attention due to their potential to integrate the outstanding properties of both materials. While diamond and graphene individually exhibit ultrahigh thermal conductivity, the phonon transport characteristics of their covalently bonded superlattice structures remain poorly understood, especially regarding the role of strong <em>sp</em>²-<em>sp</em>³ interfaces. This lack of understanding hampers the rational design of carbon-based composites for efficient thermal management.</div><div>In this study, we employ non-equilibrium molecular dynamics simulations to systematically investigate phonon-mediated thermal transport in diamond-graphene superlattices. We demonstrate that the interfacial thermal conductance reaches 6.33 × 10⁹ W/m²K, a value significantly higher than most other covalently bonded heterostructures, owing to strong carbon–carbon bonding and low atomic mass. Moreover, the thermal conductivity exhibits a distinct non-monotonic dependence on periodic length, reflecting a transition from coherent to incoherent phonon transport regimes: it decreases below a coherence threshold and increases beyond it. Temperature variation from 200 to 600 K does not shift the coherence-period minimum, indicating that the coherence–incoherence crossover is robust within this temperature range.</div><div>These findings address a key knowledge gap in understanding heat conduction in covalently bonded carbon superlattices. They provide fundamental insights into the mechanisms of phonon coherence and interfacial transport, offering valuable guidance for the design of advanced thermal interface materials and next-generation nanoelectronic devices where efficient heat dissipation is essential.</div></div>","PeriodicalId":11266,"journal":{"name":"Diamond and Related Materials","volume":"159 ","pages":"Article 112880"},"PeriodicalIF":5.1,"publicationDate":"2025-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145154532","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":"High surface area activated carbon with mesoporous structure from pyrolyzed Psidium guajava L. peel: Characterization and experimental design optimization for methyl violet 2B dye removal","authors":"Marzirah Marzuki ,&nbsp;Ali H. Jawad ,&nbsp;Nur Ievana Insyirah Mohd Zazulir ,&nbsp;Raja Razuan Raja Deris ,&nbsp;Ruihong Wu ,&nbsp;Zeid A. ALOthman","doi":"10.1016/j.diamond.2025.112869","DOIUrl":"10.1016/j.diamond.2025.112869","url":null,"abstract":"<div><div>Herein, guava (<em>Psidium guajava L.</em>) peel (GP) was employed as a feedstock to produce a mesoporous and high surface area activated carbon (GP-AC) material by thermochemical pyrolysis process assisted ZnCl₂ activation. Several characterization methods such as XRD, specific surface area (BET), TGA FSEM-EDX, FTIR, and pH_pzc were employed to investigate the physicochemical properties of GP-AC. The BET result shows a high surface area of GP-AC (1267 m²/g) with a mesoporous structure and pore diameter (3.41 nm). The applicability of GP-AC as a sustainable adsorbent for methyl violet 2B (MV 2B) dye was evaluated and statistically optimized <em>via</em> Box Behnken design (BBD) and desirability function approach. The desirability ramp reveals the best MV 2B removal (97.2 %) was achieved after 17 min of the adsorption time, pH of 9.3 and GP-AC dose of 0.09 g/0.1L. According to the adsorption isotherm and kinetic investigations, the adsorption of MV 2B onto GP-AC surface was well explained by Langmuir and Freundlich isotherm models, and pseudo second order (PSO) respectively. The adsorption capacity of GP-AC adsorption for MV 2B dye was found to be 169.9 mg/g at 25 °C. The thermodynamic functions indicate a spontaneous and endothermic adsorption process for MV 2B dye by GP-AC. Various electrostatic forces, π-π attraction, and hydrogen bonding can be considered the most probable options for loading MV 2B dye onto GP-AC surface. Overall GP-AC shows preferable surface area and outstanding performance in eliminating MV 2B dye from the contaminated water.</div></div>","PeriodicalId":11266,"journal":{"name":"Diamond and Related Materials","volume":"159 ","pages":"Article 112869"},"PeriodicalIF":5.1,"publicationDate":"2025-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145154449","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":"Graphene-integrated bamboo biochar with enhanced anisotropic heat transfer for directional solar-thermal energy storage","authors":"Huanan Li ,&nbsp;Riyi Lin ,&nbsp;Liqiang Zhang ,&nbsp;Jinyu Li ,&nbsp;Chenxing Huang ,&nbsp;Xinwei Wang","doi":"10.1016/j.diamond.2025.112870","DOIUrl":"10.1016/j.diamond.2025.112870","url":null,"abstract":"<div><div>The study of anisotropic composite phase change materials (CPCMs) is crucial for enhancing the efficiency of solar energy storage and conversion. However, existing directional CPCMs exhibit limitations including complex fabrication processes, low heat transport and poor stability, constraining their development and application. In this work, a simple and mechanized method based on flattening, slicing, spraying, self-assembly and carbonization technology is developed for the preparation of lamellar carbonized bamboo skeleton materials with enhanced directional thermal transport, which realizes the directional bonding arrangement of graphene and avoids agglomeration. The skeleton material exhibits a macroscopic, mesoscopic, and microscopic pore structure and excellent radial mechanical compression properties, and the porosity reaches 76.6 % without the need for chemical reagents. An anisotropic high-efficiency photothermal lamellar carbonized bamboo-derived CPCM is successfully developed by vacuum impregnation using paraffin as phase change material (PCM), and the heat storage density is as high as 108.25 kJ·kg⁻¹. Based on this method, the longitudinal thermal conductivity and anisotropy of oriented CPCM are also synergistically improved, reaching 1.39 W·m⁻¹·K⁻¹ and 2.017, respectively. The significant anisotropy improves the directional transport and storage of solar heat and reduces heat loss. Additionally, the addition of graphene increases the light absorption of the CPCM to 98 %, resulting in a solar thermal storage efficiency of 91.25 % under 1.6 solar radiation intensities. Meanwhile, the shape-stable CPCM's excellent permeability resistance and stability promote its application in practice. The work has broad application potential in the application of medium and low temperature solar heat storage.</div></div>","PeriodicalId":11266,"journal":{"name":"Diamond and Related Materials","volume":"159 ","pages":"Article 112870"},"PeriodicalIF":5.1,"publicationDate":"2025-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145154358","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":"Designing 3D hierarchical assembled Co/CNT structures through in-situ growth of carbon nanotube arrays on coral-like Co for enhanced electromagnetic wave absorption","authors":"Yuan Shu ,&nbsp;Wei Dong ,&nbsp;Pan Duan ,&nbsp;Weibin Deng ,&nbsp;Hongyao Jia","doi":"10.1016/j.diamond.2025.112877","DOIUrl":"10.1016/j.diamond.2025.112877","url":null,"abstract":"<div><div>Material consist of carbon nanotube (CNT) and magnetic nanoparticles could enhance its electromagnetic (EM) wave absorption performance by integrating the characteristics of relevant materials, showing notable potential in EM wave loss. In this study, an innovative H₂-free, low-temperature CVD strategy is developed to rationally design 3D hierarchical assembled Co/CNT structures as high-performance EM wave absorbers, utilizing ethanol (C₂H₅OH) as carbon source and urchin-like Co(CO₃)₀.₅(OH)·₀.₁₁H₂O nanoparticles as the catalytic precursor. Significantly, in 3D hierarchical assembled Co/CNT structures, Co nanospheres-encapsulating CNTs are in-situ grown on coral-like Co in an array arrangement, which not only facilitates electron transport between the two components but also generates numerous heterointerfaces, thereby enhancing conductive loss, which greatly amplifies EM wave attenuation. Owing to the advantages of special 3D hierarchical assembled structure, abundant heterogeneous interfaces, hybrid of dielectric/magnetic components and coral-like Co-CNT array conductive network, multiple loss modes are manifested in the EM wave absorption process, involving conductive loss, dipole polarization, interface polarization, multiple scattering, magnetic loss, and good impedance matching, boosting EM wave absorption. The graphitization degree of CNTs and the crystallinity of Co are controlled by varying the CVD temperature of 3D hierarchical assembled Co/CNT structure, thereby effectively regulating the EM parameters and EM wave dissipation properties. At a synthesis temperature of 650 °C, an EM wave absorption of −31.65 dB and an effective bandwidth of 3.91 GHz are achieved with filler loading of 15 wt%. The preparation of this 3D hierarchical assembled Co/CNT structures just requires a low temperature, obviating the requirement for H₂ and nanoscale catalysts. Furthermore, it possesses a distinctive layered assembly configuration and demonstrates superior EM wave absorption performance even under low-loading conditions. Such characteristics render it applicable in the aerospace domain, including scenarios like the absorbing coatings on aircraft surfaces and the absorbents utilized for honeycomb impregnation.</div></div>","PeriodicalId":11266,"journal":{"name":"Diamond and Related Materials","volume":"159 ","pages":"Article 112877"},"PeriodicalIF":5.1,"publicationDate":"2025-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145154448","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":"Characterization of thermally heat-treated polyacrylonitrile carbon fibers","authors":"Aaron R. Ginsparg ,&nbsp;Jeremy L. Watts ,&nbsp;William G. Fahrenholtz ,&nbsp;Matthew B. Dickerson ,&nbsp;Kaitlin N. Detwiler ,&nbsp;Zachary E. Brubaker ,&nbsp;Gregory E. Hilmas","doi":"10.1016/j.diamond.2025.112875","DOIUrl":"10.1016/j.diamond.2025.112875","url":null,"abstract":"<div><div>This study investigates the graphitization process of polyacrylonitrile (PAN) carbon fibers by subjecting commercial fibers to thermal heat treatment at temperatures ranging from 1400 to 2100 °C in 100 °C increments, using either argon or nitrogen gas atmospheres. Changes in crystallinity, surface morphology, and lattice parameters were analyzed for two commercial carbon fibers using X-ray diffraction, scanning electron microscopy, and Raman spectroscopy. Results indicated minimal changes in surface morphology with increasing heat-treatment temperature; however, crystallinity significantly increased. Crystallinity changes were more strongly dependent on temperature rather than gas atmosphere or fiber type. At intermediate heat-treatment temperatures (1600–1800 °C), fibers treated in argon showed a slight preference for graphitization. The highest level of graphitization was measured at 2100 °C. Crystallite size increased as the intensity ratio of the D1 to G Raman peaks increased, reaching a peak around ~1800 °C, after which the ratio started to decrease. This behavior aligns with Ferrari's three-stage model of carbon crystallization and is consistent with both the Marie-Mering degree of graphitization and Brubaker's Integrated Absolute Differential models, all of which describe the transformation from an amorphous to a more graphitic structure. At the higher heat-treatment temperatures, the changes between atmospheres and fiber types were measured to converge to similar levels of graphitization. This study evaluates the progressive change in commercial grade carbon fibers when heat-treated.</div></div>","PeriodicalId":11266,"journal":{"name":"Diamond and Related Materials","volume":"159 ","pages":"Article 112875"},"PeriodicalIF":5.1,"publicationDate":"2025-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145154453","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}