Materials Chemistry and Physics最新文献

{"title":"Magnetodielectric, electrical, and physicochemical evaluations of rare earth La3+doped spinel nano ferrites for microwave absorption applications","authors":"Muzamil Ahmed Warsi ,&nbsp;Muhammad Hashim ,&nbsp;Muhammad Imran Arshad ,&nbsp;Sagr Alamri ,&nbsp;Abdullah Almohammedi ,&nbsp;Majid Niaz Akhtar","doi":"10.1016/j.matchemphys.2025.130889","DOIUrl":"10.1016/j.matchemphys.2025.130889","url":null,"abstract":"<div><div>Electromagnetic (EM) pollution represents a significant challenge to human health, driven by the proliferation of high-frequency electromagnetic waves generated by electronic devices. Developing advanced materials with exceptional electromagnetic wave absorption, superior shielding capabilities, and efficient energy dissipation mechanisms remains a critical research frontier in materials science and electromagnetic interference management. Magnetic nanoparticles display exceptional and distinctive magnetic properties due to their elevated surface-to-volume ratio and diverse crystal structures. The characteristics of these nanoparticles are substantially affected by their synthesis method. Spinel ferrite made of Ni₀.₃Mn₀.₂Cd₀.₂₅Co₀.₂₅Fe2-xLa_xO₄ (x = 0.0, 0.01, 0.03, 0.05, 0.07) was prepared using the sol-gel auto-ignition method. X-ray diffraction (XRD) research provided comprehensive structural characterization, confirming the successful formation of the spinel crystal structure. The study demonstrated the formation of secondary crystalline phases upon the gradual increase in La concentration. This showed how the material's structure changed over time with dopant concentration. The crystallite size ranged from 48.28 to 58.07 nm. Advanced spectroscopic and analytical techniques such as FTIR, UV–Vis, XRD, and VSM were employed to evaluate the material's structural and physical properties. The FTIR analysis identified two significant bands between 572.76 and 598.75 cm⁻¹ and 443.97 and 462.38 cm⁻¹. These bands correspond to vibrations at the A and B sites, respectively. The optical band gap diminished from 3.41 eV to 2.96 eV with the augmentation of La³⁺ concentration. Dielectric experiments conducted with an LCR meter demonstrated frequency-dependent characteristics, wherein the dielectric constant, dielectric loss, and tangent loss were reduced, but AC conductivity increased with frequency. M_s diminished from 87.32 emu/g to 53.84 emu/g, Mᵣ declined from 38.41 emu/g to 4.68 emu/g, and Hc first fell from 737 Oe to 171 Oe, thereafter experiencing a minor increase to 226 Oe with more La³⁺ doping. The narrow hysteresis loops validated the materials' soft magnetic characteristics. The lowest reflection loss of −37.89 dB was achieved at 0.48 GHz for x = 0.03. At higher doping concentrations of x = 0.05 and x = 0.07, the reflection loss values are-28.25 dB and −28.17 dB, respectively. The La³⁺-substituted Ni–Mn–Cd–Co nanocrystalline ferrites have properties that can be changed, making them good choices for use in electronics, magnetic systems, and other microwave high-frequency applications.</div></div>","PeriodicalId":18227,"journal":{"name":"Materials Chemistry and Physics","volume":"341 ","pages":"Article 130889"},"PeriodicalIF":4.3,"publicationDate":"2025-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143874995","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":"Granulated activated carbon oxidation, a comparison between wet-chemistry and plasma approaches in dry and wet forms","authors":"Nathalie de la Torre-Miranda,&nbsp;Pierre Eloy,&nbsp;Eric M. Gaigneaux,&nbsp;Sophie Hermans","doi":"10.1016/j.matchemphys.2025.130878","DOIUrl":"10.1016/j.matchemphys.2025.130878","url":null,"abstract":"<div><div>Activated carbon oxidation was explored by comparing two approaches: wet-chemistry (employing HNO₃ or H₂O₂ solutions) and glidarc plasma exposure, working with different reactor configuration modes and gases. The oxidized samples were characterized by XPS, FTIR, N₂-physisorption, SEM, Boehm titrations and compared in terms of oxidation efficiency, created functionalities and morphological changes. Excellent oxidation is accomplished by exposing activated carbon in solid form directly to the plasma plume and the oxidized material shows characteristics similar to HNO₃ oxidized carbon: high oxidation degree with abundance of carboxylic acids. In contrast, if the carbon is exposed to plasma while being in water suspension, the oxidation degree is lower and the main created functions are phenols, with equivalent characteristics to H₂O₂ oxidized carbon. Additionally, it was demonstrated that the carbon's oxidation degree and type of oxygen functionalities seem little influenced by the type of gas used for plasma generation, though the presence/absence of water could enhance/diminish the nitrates or O–H containing species present in the oxidized carbons. Plasma oxidation has advantageously a lower impact on the carbon's textural properties than HNO₃ oxidation, while obtaining high oxidation efficiency, and the introduced oxygen functions seem stable for at least 6 weeks after plasma exposure.</div></div>","PeriodicalId":18227,"journal":{"name":"Materials Chemistry and Physics","volume":"341 ","pages":"Article 130878"},"PeriodicalIF":4.3,"publicationDate":"2025-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143855573","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":"Bio-derived ionic liquids for iron surface protection: A multiscale investigation of cholinium lignin-based inhibitors","authors":"Hassane Lgaz ,&nbsp;Mouslim Messali ,&nbsp;Han-seung Lee ,&nbsp;Murad M.A. Abualrejal","doi":"10.1016/j.matchemphys.2025.130894","DOIUrl":"10.1016/j.matchemphys.2025.130894","url":null,"abstract":"<div><div>Cholinium lignin-based ionic liquids have emerged as attractive candidates for eco-friendly corrosion inhibition in corrosive environments, owing to their biocompatibility and rich functionality. In this work, a synergistic suite of computational techniques; ranging from density functional theory (DFT) and conductor-like screening model (COSMO-RS) to molecular dynamics (MD) and self-consistent charge density functional tight-binding (SCC-DFTB); was employed to unravel the anticorrosive behavior of Trimethyl-β-hydroxyethyl-ammonium gallate (CH-GAL), syringate (CH-SYR), and vanillate (CH-VAN) on Fe(110). DFT calculations showed that CH-SYR possessed a slightly narrower HOMO–LUMO gap (3.49 eV) and higher electron affinity than the other two, pointing to enhanced reactivity and stronger metal–inhibitor orbital overlap. COSMO-RS reveals the anion's pronounced hydrogen-bond acceptor profile, promoting robust solvation and competitive adsorption at the metal–solution interface. MD simulations confirmed stable interfacial arrangements, with the anionic moiety generally lying parallel to the iron surface to maximize contact. SCC-DFTB evaluations corroborate these observations, attributing the most exothermic adsorption energy (−3.834 eV) to CH-SYR's multi-site Fe–O coordination, followed by CH-GAL (−3.029 eV) and CH-VAN (−2.247 eV). Together, these results underscore the promise of tailoring both the lignin anion and cholinium cation to optimize electron donation, surface coverage, and solvation effects, thereby paving the way for the design of next-generation, bio-derived corrosion inhibitors with minimal environmental impact.</div></div>","PeriodicalId":18227,"journal":{"name":"Materials Chemistry and Physics","volume":"341 ","pages":"Article 130894"},"PeriodicalIF":4.3,"publicationDate":"2025-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143865232","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":"One-step synthesis of TiO2@MWCNT by plasma reactor for wastewater purification","authors":"M. El-khatib ,&nbsp;Awatif Rashed Z. Almotairy ,&nbsp;Bassma H. Elwakil ,&nbsp;Seham Sater Alhelaify ,&nbsp;Eman Fayad ,&nbsp;Keshav Raj Paudel ,&nbsp;Hanadi A. Katouah ,&nbsp;Ahmed M. Eldrieny","doi":"10.1016/j.matchemphys.2025.130892","DOIUrl":"10.1016/j.matchemphys.2025.130892","url":null,"abstract":"<div><div>The contamination of water resources by the textile dyeing industry, organic waste, and agricultural residue has become a significant global environmental crisis, highlighting the urgent issue of water pollution. On the other hand, electrical discharge machining (EDM) is a prevalent method to synthesize Titanium alloy (an important alloy with exceptional physicochemical and thermo-mechanical characteristics). Hence, in the present study, EDM was used to synthesize titanium-based carbon nanocomposite TiO₂@MWCNT as a remediation tool for wastewater treatment. Transmission electron microscope (TEM), X-ray diffraction (XRD), stability via zeta potential, Ultra-violet (UV) and Fourier Transform Infrared (FTIR) analysis, polycrystalline and elemental identification, and optical characteristics were used to study the geometry and architecture phase of the prepared nanocomposite. According to the TEM images, all nanoparticles were hexagonal with less than 20 nm, the crystallite size was less than 2 nm and surrounded by graphene nanosheets. FTIR peaks recorded in the range of 461–501 and 542 cm⁻¹ confirmed the formation of Ti–C vibrational mode, and the zeta potential was −25 mV, indicating the nanoparticles' high stability. MB dye was examined by UV spectroscopy, and a high absorbance peak at 660 nm was found. Dye remediation studies revealed that the greatest percentage of dye elimination (79 %) was achieved by raising the contact duration between the prepared TiO₂@MWCNT and the wastewater to 90 min. Furthermore, the proportion of dye elimination increased quickly (up to 1 g/100 mL), fitting with the Langmuir adsorption isotherm model. TiO₂@MWCNT nano adsorbents exhibited good adsorptive activity even after 5 adsorption and desorption cycles. Moreover, TiO₂@MWCNT's antibacterial activity was found to be concentration-dependent with bactericidal effect through bacterial cell lysis and deformation. In conclusion, the prepared TiO₂@MWCNT can be used as an effective, stable, and reusable tool for wastewater treatment.</div></div>","PeriodicalId":18227,"journal":{"name":"Materials Chemistry and Physics","volume":"341 ","pages":"Article 130892"},"PeriodicalIF":4.3,"publicationDate":"2025-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143850651","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":"Investigations on low-melting glasses in ZnO–CuO–Bi2O3–B2O3 system for sealing vacuum glasses","authors":"Yifeng He ,&nbsp;Chaoyuan Li ,&nbsp;Xiuying Li,&nbsp;Lawrence Cooper,&nbsp;Zhuohao Xiao","doi":"10.1016/j.matchemphys.2025.130868","DOIUrl":"10.1016/j.matchemphys.2025.130868","url":null,"abstract":"<div><div>The dependence of glass forming ability, structure and properties on the composition of lead-free low-melting glassy solders in the ZnO–CuO–Bi₂O₃–B₂O₃ system was studied in the present paper. X-ray diffractometer (XRD), dilatometer, differential thermal analyzer (DTA) and infrared spectrometer (IR) were used to study the glass-forming ability, thermal properties and structure. The leaching rate method was used to evaluate chemical durability. An experiment utilizing pellet heating on plate glass substrates was conducted to assess the wettability and sealing temperatures(T_s) of solders. The sealing strength of glassy solder was investigated by using the crossover method. Glassy solders with the content of Bi₂O₃ in the range of 60.8–80.8 wt% were prepared by the conventional melting and air quenching technique. They maintain a vitreous state even when heated at temperatures around T_s for as long as 0.5 h except for solders with more than 20 mol% CuO. It is favourable to prepare glassy solders that can be used as edge sealing materials for tempered vacuum glass by using compositions with the contents of B₂O₃≤25 mol%, CuO≤ 20 mol% and Bi₂O₃ in the range of 35∼40 mol% because their comprehensive properties are excellent and meets the requirements for vacuum glass sealing. The water resistance and thermal expansion coefficients of these solders closely match that of plate glass. Their sealing temperatures are below 400 °C and they can adhere very well onto plate glass after sealing.</div></div>","PeriodicalId":18227,"journal":{"name":"Materials Chemistry and Physics","volume":"340 ","pages":"Article 130868"},"PeriodicalIF":4.3,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143834502","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":"The influence of preparation method on the efficiency of clay-carbon composites for detection of 4- aminoantipyrine","authors":"Gordana Stevanović ,&nbsp;Zorica Mojović ,&nbsp;Danica Bajuk Bogdanović ,&nbsp;Tanja Barudžija ,&nbsp;Nataša Jović-Jovičić ,&nbsp;Predrag Banković ,&nbsp;Marija Ajduković","doi":"10.1016/j.matchemphys.2025.130881","DOIUrl":"10.1016/j.matchemphys.2025.130881","url":null,"abstract":"<div><div>Smectite-rich bentonite clay was used to synthesize a chitosan-smectite nanocomposite. The resulting nanocomposite underwent two carbonation procedures: air-limitation pyrolysis and hydrothermal treatment. The obtained clay-carbon composites were characterized using XRD analysis, FT-IR, and Raman spectroscopy. The point of zero charge was determined for both composites. Electrochemical characterization was performed via cyclic voltammetry and electrochemical impedance spectroscopy. The electrochemical activity of carbon paste electrodes modified with the clay-carbon composites was evaluated for 4-aminoantipyrine (4-AAP) detection in Britton-Robinson buffer (pH 3–9) using cyclic voltammetry. The sensor based on the hydrothermally synthesized composite was further tested by square wave voltammetry, achieving a sensitivity of 0.0125 μA/μM and a detection limit (LOD) of 0.4 μM. The sensor demonstrated satisfactory performance when tested in real urine samples.</div></div>","PeriodicalId":18227,"journal":{"name":"Materials Chemistry and Physics","volume":"340 ","pages":"Article 130881"},"PeriodicalIF":4.3,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143834503","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":"Factors influencing austenite stability during Inter-critical annealing and effect on mechanical properties of low-density medium Mn steels","authors":"Kishan Bharti,&nbsp;Nitin Kumar Sharma","doi":"10.1016/j.matchemphys.2025.130877","DOIUrl":"10.1016/j.matchemphys.2025.130877","url":null,"abstract":"<div><div>Addition of lightweight elements to medium-Mn steels has been seen as a potential method to reduce the density of advanced high strength steels (AHSS). Reduction in density of steels, especially in the automotive sector, leads to weight reduction of automobile and hence contributes towards improved fuel efficiency and lower emission of harmful gases. Present work investigates the addition of 3 % Al, with and without 1 % Si, to Fe–8Mn-0.2C medium-Mn steel system aiming to not only obtain an improved combination of strength and ductility, but also investigate the austenite stability. Hot-rolled steels were subjected to intercritical annealing (IA) followed by water quenching. Presence of Al and/or Si helped in broadening the IA window, thus allowing flexibility for selection of IA temperature. Uniaxial tensile test results show that the Si-free steel after IA performed better in terms of obtaining a product of strength and elongation (PSE) value of 61 GPa% as compared to PSE value of 41 GPa% for Si-containing steel. Microstructural characterization using electron backscatter diffraction (EBSD) and X-ray diffraction (XRD) revealed the presence of <span><math><mrow><mi>α</mi></mrow></math></span>-ferrite and austenite with negligible amount of martensite in both steels. However, the fraction of retained austenite was found to be significantly higher in Si-free steel (45 %) as compared to the Si-containing steel (19 %). Superior mechanical performance of Si-free steel is attributed to its higher retained austenite fraction and relatively slower TRIP effect. The role of IA temperature in determining the stability of austenite against transformation to martensite during cooling was investigated with the help of thermodynamic equilibrium predictions assisted with Koistinen-Marburger model for retained austenite calculations. Results indicate that additional factors related to local microstructural heterogeneity such as partitioning of elements and grain size differences may have contributed to the higher than expected austenite stability. Further, mechanical response of the obtained microstructural constituents is discussed in terms of the mechanical stability of retained austenite. Analysis related to the transformation kinetics of retained austenite revealed a lower value of mechanical stability parameter for Si-free steel, thus explaining the slower TRIP effect.</div></div>","PeriodicalId":18227,"journal":{"name":"Materials Chemistry and Physics","volume":"341 ","pages":"Article 130877"},"PeriodicalIF":4.3,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143838706","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":"Gold nanoparticles modified Cu2O/ZnO nanorod arrays synthesized with anodic aluminum oxide template for high performance non-enzymatic glucose sensor","authors":"Hsi-Chao Chen ,&nbsp;Ying-Sheng Lin ,&nbsp;Ming-Hsien Yen ,&nbsp;Jia-Yu Lin","doi":"10.1016/j.matchemphys.2025.130886","DOIUrl":"10.1016/j.matchemphys.2025.130886","url":null,"abstract":"<div><div>In this study, gold nanoparticles (Au NPs) modified cuprous oxide (Cu₂O) on zinc oxide nanorod arrays (ZnO NRAs) prepared by anodic aluminum oxide (AAO) template was used as heterogeneous sensing electrodes. Among them, the ZnO NRAs can increase the sensing contact area, and the localized surface plasmon resonance (LSPR) of Au NPs can gain sensing current and stability. First of all, the experiment was conducted to grow array-shaped holes on the evaporated aluminum film through anodizing treatment. To prepare a fully formed alumina template with the time needed of the 2nd anodization was 3, 4, and 5 min, respectively. Secondly, the technique of electroplating was employed to grow ZnO nanorods in array holes for 10 and 20 min, respectively, to prepare a transparent ZnO NRAs. Thirdly, Cu₂O films were electrodeposited on the surface of ZnO NRAs for 60, 90, and 120 s, respectively, considering the pH value from 8, 9, 10 to 11. Finally, chemically synthesized Au NPs were used and dispersed uniformly through Nafion and dropwise coated on Cu₂O/ZnO NRA/ITO to form a heterogeneous sensing electrode. The sensing electrodes were analyzed by the electrochemical measurement of its redox reaction characteristics, and the best sensitivity, linearity and fitting superiority were determined. It was found that there were two linear sections of high and low concentration. These experimental results indicate that the LSPR of Au NPs could increase the sensing slope from 25.10 to 29.52 μAmg⁻¹dL. The high and low concentration sensitivity increased from 958.41 &amp; 320.03 to 973.97 &amp; 437.26 μAmM⁻¹cm⁻². Regarding the anti-interference test, the non-organic glucose sensing response reached the highest level, and the stability remained above 92 % after two weeks.</div></div>","PeriodicalId":18227,"journal":{"name":"Materials Chemistry and Physics","volume":"341 ","pages":"Article 130886"},"PeriodicalIF":4.3,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143838708","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":"Oxidation behaviour of microwave hybrid heating processed CoCrNiTiMo high entropy alloy cladding","authors":"Purushottam Mishra,&nbsp;S.B. Mishra","doi":"10.1016/j.matchemphys.2025.130883","DOIUrl":"10.1016/j.matchemphys.2025.130883","url":null,"abstract":"<div><div>CoCrNiTiMo high entropy alloy (HEA) cladding is developed over SA213 T91 steel substrate through a microwave hybrid heating process. The mechanical and microstructural properties of CoCrNiTiMo HEA cladding are analysed. The average thickness of the fabricated clad is 826.43 μm. The cyclic oxidation tests of the cladded and uncladded samples are conducted for 30 cycles of 1 h of heating at 800 °C and 20 min of cooling at room temperature. After completing 30 cycles of oxidation tests, the uncladded specimen exhibited a weight gain of 13.19 mg/cm², whereas the HEA-cladded counterpart showed a comparatively lower weight gain of 8.70 mg/cm². This substantial difference indicates that the HEA cladding reduced the oxidation rate by approximately 34 % compared to the uncladded sample. The XRD analysis revealed the formation of Ni, Co, Cr - rich FCC phase and Cr, Mo, Ti - rich BCC phase in the cladded sample. A continuous TiO₂ layer is also observed on the oxidised cladding specimen surface. The cladded sample showed better oxidation resistance than uncladded T91 steel due to the formation of the protective NiO, NiCr₂O₄, CoCr₂O₄, and Ni₃TiO₅ oxides and spinel.</div></div>","PeriodicalId":18227,"journal":{"name":"Materials Chemistry and Physics","volume":"341 ","pages":"Article 130883"},"PeriodicalIF":4.3,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143850655","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":"Role of H2O for forming O-containing groups during the secondary oxidation stage of graphite","authors":"Zhang Xiyue ,&nbsp;Sun Hongjuan ,&nbsp;Peng Tongjiang ,&nbsp;Liu Bo ,&nbsp;Tang Xv","doi":"10.1016/j.matchemphys.2025.130871","DOIUrl":"10.1016/j.matchemphys.2025.130871","url":null,"abstract":"<div><div>To investigate the impact of H₂O on the formation of O-containing functional groups during the secondary oxidation stage in the oxidation process of graphite, graphite oxide (GO) with varying types and quantities of O-containing functional groups is prepared by precisely controlling the reaction temperature. In the initial oxidation stage, Mn₂O₇ serves as the primary oxidizing agent. However, the diffusion of Mn₂O₇ between graphite layers is hindered by its significant volume, thereby complicating the oxidation of carbon atoms within the graphite layers. The initial oxidation stage primarily involves the intercalation of graphite, during which carbon atoms located at the edges of the atomic layers or surface defects undergo oxidation, resulting in the formation of carboxyl, carbonyl and other O-containing functional groups. The secondary oxidation stage is characterized by the introduction of a large number of O-containing functional groups in the GO. The introduction of H₂O transforms the main oxidizing substance into MnO₄⁺, which facilitates its penetration into the graphite layer and rapidly diffuse, thereby enabling the oxidation of carbon atoms within the graphite layers to form hydroxyl, epoxy and other O-containing functional groups. By controlling the reaction time and temperature during the secondary oxidation stage, it is possible to alter both type and content of O-containing functional groups in GO. Prolonging the reaction time or increasing the reaction temperature can reduce hydroxyl content while increasing epoxy and carbonyl groups in GO, consequently leading to an increase in structural defects as well as a decrease in cation exchange capacity. The results provide an experimental and theoretical foundation for customizing GO with specific functionalities at the chemical structure level.</div></div>","PeriodicalId":18227,"journal":{"name":"Materials Chemistry and Physics","volume":"340 ","pages":"Article 130871"},"PeriodicalIF":4.3,"publicationDate":"2025-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143834504","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}