M.F. Hardman , M.Y. Lai , C.M. Breeding, S.C. Eaton-Magaña, V.A. Schwartz
{"title":"A statistical evaluation of the spectroscopic features in natural diamonds with the 480 nm absorption band","authors":"M.F. Hardman , M.Y. Lai , C.M. Breeding, S.C. Eaton-Magaña, V.A. Schwartz","doi":"10.1016/j.diamond.2025.112277","DOIUrl":"10.1016/j.diamond.2025.112277","url":null,"abstract":"<div><div>Natural diamonds referred to as “480 nm band diamonds” in the <em>gem</em> trade are colored by a broad absorption band centered at ∼480 nm in the visible range. A subset, known as “chameleon diamonds,” have green ± gray colors and a reversible color change from greenish to orange/yellow when heated above ∼120 °C, or when left in the dark for an extended period. The atomic defect(s) responsible for the 480 nm absorption band and chameleonism are debated. To evaluate the body color and spectroscopic data for more than one hundred 480 nm band diamonds with or without color change property, we apply principal component analysis. Photoluminescence spectra evaluated in this study were acquired using 455 and 785 nm laser excitations at liquid nitrogen temperatures (77 K). Several features – including a peak at 475.7 nm – occur more frequently and with greater intensities in chameleon than non-chameleon 480 nm band diamonds. Chameleon diamonds have stronger 793.5 nm peak (Ni-V-N) but weaker 882.9/884.6 nm doublets (Ni<img>V), documenting a distinct difference in the form of nickel-related defects in the diamond lattice. For these spectroscopic features there is progressive variation between those with or without visible chameleonism rather than discrete separation, suggesting that the defect(s) responsible for chameleonism may be present in low concentrations even in “non-chameleon” 480 nm band diamonds. Statistical analysis of spectroscopic features can be a robust tool to evaluate the presence of defects possibly associated with chameleonism in 480 nm band diamonds, even when a color change cannot be identified visually.</div></div>","PeriodicalId":11266,"journal":{"name":"Diamond and Related Materials","volume":"155 ","pages":"Article 112277"},"PeriodicalIF":4.3,"publicationDate":"2025-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143783221","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":"Efficient fabrication of NiFe2O4/gCN composite as an excellent electroactive catalyst for HER in alkaline media","authors":"Meshal Fatima , Imen Safra , Tahani Rahil Aldhafeeri , Syed Kashif Ali , Abhinav Kumar","doi":"10.1016/j.diamond.2025.112286","DOIUrl":"10.1016/j.diamond.2025.112286","url":null,"abstract":"<div><div>Nowadays, water splitting is the most well-known sustainable energy source and an essential need. It is now a major initiative to design an effective, high-performing and long-lasting electrocatalyst to increase water-splitting efficiency. A non-toxic, economical and sustainable composite material, NiFe<sub>2</sub>O<sub>4</sub>/gCN was fabricated via a hydrothermal process to improve water-splitting efficiency. The structural, surface area and morphological properties were analyzed using multiple analytical approaches like X-ray diffraction (XRD), Brunauer Emmett Teller's (BET) and Scanning electron microscopy (SEM). A 3-electrode setup in 1.0 M KOH was also employed to determine electrochemical characteristics of NiFe<sub>2</sub>O<sub>4</sub>/gCN nanocomposite, which showed much low overpotential (η) (−173 mV) at current density (j) (10 mA/cm<sup>2</sup>). The composite material has higher HER performance with a larger electrochemical surface area of 257.5 cm<sup>2</sup>, a low charge transfer resistance (R<sub>ct</sub>) of 1.03 Ω and remarkable durability for 50 h. A substantially lower Tafel value (61 mV/dec) was discovered following closer inspection, indicating that the NiFe<sub>2</sub>O<sub>4</sub>/gCN nanocomposite had higher electrocatalytic efficiency and faster reaction kinetics. Because of its enormous surface area, the nanohybrid mentioned above (NiFe<sub>2</sub>O<sub>4</sub>/gCN) holds considerable potential for water electrolysis and other electrochemical reactions. Consequently, the generated nanocomposite appears to be an excellent electroactive catalyst for HER and energy conversion applications.</div></div>","PeriodicalId":11266,"journal":{"name":"Diamond and Related Materials","volume":"155 ","pages":"Article 112286"},"PeriodicalIF":4.3,"publicationDate":"2025-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143825976","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":"Density distribution analysis of near-interface traps in Al2O3/diamond MOS structure","authors":"Xueqia Zhang, Xufang Zhang, Mingkun Li, Jing Zhang","doi":"10.1016/j.diamond.2025.112275","DOIUrl":"10.1016/j.diamond.2025.112275","url":null,"abstract":"<div><div>Inversion-type p-channel diamond MOSFETs have been developed and normally-off characteristics have been realized. However, they still suffer from low channel mobility, despite water vapor annealing significantly reducing the interface state density at the Al<sub>2</sub>O<sub>3</sub>/diamond MOS interface. We have also observed notable frequency dispersion of capacitance under accumulation conditions, which is mainly attributed to near-interface traps (NITs). In this work, we focused on characterizing NITs in Al<sub>2</sub>O<sub>3</sub>/diamond structures at 300 K, 350 K, and 400 K, using a distributed circuit model. Various possible distributions for NITs were considered, including box-shaped, linearly-decaying, exponentially-decaying, and uniform distributions, to fit the capacitance–frequency (<em>C–f</em>) characteristics at these temperatures. Based on error comparisons from the fitting results, the uniform distribution exhibited the smallest fitting errors for <em>C–f</em>. The NIT density and other related parameters were extracted based on the best-fitting results, with possible physical origins discussed. This work lays the groundwork for further passivation of NITs, which is critical for improving device performance.</div></div>","PeriodicalId":11266,"journal":{"name":"Diamond and Related Materials","volume":"155 ","pages":"Article 112275"},"PeriodicalIF":4.3,"publicationDate":"2025-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143777043","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}
Rui Zhang, Duoyu Zhou, Kenan Yi, Songsong Xu, Lina Su, Jianhua Liu, Li Li, Fengyang Yu
{"title":"One-step carbonization-activation synthesis of pomelo peel derived N, O-doped porous carbon for enhanced supercapacitve performance","authors":"Rui Zhang, Duoyu Zhou, Kenan Yi, Songsong Xu, Lina Su, Jianhua Liu, Li Li, Fengyang Yu","doi":"10.1016/j.diamond.2025.112276","DOIUrl":"10.1016/j.diamond.2025.112276","url":null,"abstract":"<div><div>Biomass-derived porous carbon has gained significant interest as ideal electrode material for supercapacitor owing to eco-sustainability, cost-effectiveness, and unique inherent microstructure. Herein, N, O co-doped porous carbons have been successfully obtained by single-step carbonization-activation method using waste pomelo peel as carbon source and KHCO<sub>3</sub>/CO(NH<sub>2</sub>)<sub>2</sub> as activators. In the synthesis process, KHCO<sub>3</sub> as a pore-forming agent plays an important role, and CO(NH<sub>2</sub>)<sub>2</sub> is used to assist the pore-forming process as well as N doping. Benefiting from high specific surface area (1378.5 m<sup>2</sup>·g<sup>−1</sup>), predominant microporous structure and O, N co-doping, the best N, O co-doped porous carbon (denoted as PKNAC) exhibits high specific capacitance (364.5 F·g<sup>−1</sup>, 1 A·g<sup>−1</sup>), favorable rate performance (retaining 63.86 %, 50 A·g<sup>−1</sup>) and good cycling durability (97.32 % retention, 20,000 cycles). Notably, the assembled quasi-flexible symmetrical supercapacitor in PVA/KOH gel electrolyte achieves the energy density of 13.7 Wh·kg<sup>−1</sup> at a power density of 350 W·kg<sup>−1</sup>. This work offers a convenient approach to prepare heteroatom-doped porous carbons from biomass waste for high-performance energy storage.</div></div>","PeriodicalId":11266,"journal":{"name":"Diamond and Related Materials","volume":"155 ","pages":"Article 112276"},"PeriodicalIF":4.3,"publicationDate":"2025-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143785168","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":"Preparation, regulatory mechanism, and full-spectrum fluorescence synthesis of ginkgo-derived trichromatic carbon dots","authors":"Changge Sun, Yuxiang Guo, Dongxu Mao, Yubao Li, Tian Li, Ren’ai Li, Qi Wang","doi":"10.1016/j.diamond.2025.112272","DOIUrl":"10.1016/j.diamond.2025.112272","url":null,"abstract":"<div><div>Biomass is a sustainable and eco-friendly resource with great potential as a precursor for synthesizing high-value carbon dots (CDs). This research synthesized full-spectrum fluorescence CDs using a microwave method with ginkgo leaves. The blue, green, and red fluorescent CDs have the following color coordinates according to the International Commission on Illumination (CIE): (0.18, 0.19), (0.32, 0.47), and (0.48, 0.29), respectively, with corresponding fluorescence quantum yields (QY) of 13.07, 6.09, and 6.72 %. The trichromatic CDs were comprehensively characterized to explore their properties and reveal the regulatory mechanisms responsible for the differences in their fluorescence behavior. Further investigations demonstrated that precise tuning of the mixing ratios of the trichromatic CDs enabled the realization of a full-spectrum fluorescence display ranging from blue to red. Additionally, the trichromatic CDs were effectively used in fluorescent inks and polyvinyl alcohol fluorescent films, achieving a novel fluorescent anti-counterfeiting effect. In conclusion, this work offers a green synthesis method for turning biomass into trichromatic CDs, addressing the complex challenge of fluorescent color modulation in CDs and providing valuable insights into potential applications and the full-spectrum fluorescence display of CDs.</div></div>","PeriodicalId":11266,"journal":{"name":"Diamond and Related Materials","volume":"155 ","pages":"Article 112272"},"PeriodicalIF":4.3,"publicationDate":"2025-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143777041","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}
Liyuan Xu , Zhijun Shi , Deng Pan , Hao Jiang , Dianlong Wang , Qingxiang Yang , Zbigniew Brytan , Xiaolei Xing , Yefei Zhou
{"title":"Response mechanism of interfacial spacing driven load induced tribological behavior and charge density evolution for C/Cu fretting","authors":"Liyuan Xu , Zhijun Shi , Deng Pan , Hao Jiang , Dianlong Wang , Qingxiang Yang , Zbigniew Brytan , Xiaolei Xing , Yefei Zhou","doi":"10.1016/j.diamond.2025.112274","DOIUrl":"10.1016/j.diamond.2025.112274","url":null,"abstract":"<div><div>Fretting is a major failure mode in electronic connectors within micro-electro-mechanical systems (MEMS). Understanding the friction-induced changes in interfacial electronic properties and their link to the structural evolution of diamond‑copper composites is crucial for controlling fretting in practical applications. This study examines the charge density evolution Δρ at the C(111)/Cu(111) interface and its intrinsic correlation with fretting performance under varying loads and interatomic spacings across different fretting directions. Synchronized variations in Δρ and potential energy difference ΔE are observed. Under constant fretting directions, the correlation coefficient <span><math><msub><mi>k</mi><msub><mi>F</mi><mi>N</mi></msub></msub></math></span> for ΔE and Δρ, and interatomic spacing Δz increase with load. When load varies, <span><math><msub><mi>k</mi><msub><mi>F</mi><mi>N</mi></msub></msub></math></span> shows an inverse trend relative to Δz under identical atomic spacing conditions, while their variation rates align. These findings provide an electron-level understanding of fretting mechanisms, offering a theoretical basis for designing durable, high-performance microelectronic devices.</div></div>","PeriodicalId":11266,"journal":{"name":"Diamond and Related Materials","volume":"155 ","pages":"Article 112274"},"PeriodicalIF":4.3,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143777044","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}
Jai Shree Bhardwaj , Anterdipan Singh , Pratima Agarwal
{"title":"Work function tuning of directly grown multi-layer graphene on silicon by PECVD and fabrication of Ag/ITO/Gr/n-Si/Ag solar cell","authors":"Jai Shree Bhardwaj , Anterdipan Singh , Pratima Agarwal","doi":"10.1016/j.diamond.2025.112271","DOIUrl":"10.1016/j.diamond.2025.112271","url":null,"abstract":"<div><div>Production of large-area, high-quality pristine graphene directly on silicon substrate from Chemical Vapor Deposition (CVD) method without metallic catalyst is highly desirable for its application in various semiconductor devices. In this work, we report synthesis of large area Graphene sheets by Plasma Enhanced Chemical Vapor Deposition (PECVD) with tunable work function based on the deposition conditions. To confirm the quality of Graphene, Raman, and XPS studies have been performed. The uniformity and surface morphology of the films has been confirmed and analyzed by FESEM. Surface roughness analysis is done by AFM. The work function has been measured through surface potential mapping by KPFM. We have observed the work function variation from 4.25 eV to 4.54 eV by varying the gas flow rates of methane and hydrogen. Later, Graphene prepared under optimized conditions were used to fabricate Ag/ITO/Gr/n-Si/Ag solar cell having efficiency of 1 %, current density of 25.52 mA/cm<sup>2</sup>, V<sub>oc</sub> of 0.13 V and FF of 0.29.</div></div>","PeriodicalId":11266,"journal":{"name":"Diamond and Related Materials","volume":"155 ","pages":"Article 112271"},"PeriodicalIF":4.3,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143777047","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 Ag-doped NiFe₂O₄ nanostructures for high-performance supercapacitor application","authors":"Sunirmal Saha , Krutika L. Routray , Anita Parida","doi":"10.1016/j.diamond.2025.112264","DOIUrl":"10.1016/j.diamond.2025.112264","url":null,"abstract":"<div><div>Silver‑nickel ferrite-doped GnPs (Ag-NiFe₂O₄-GnPs) were developed as a high-performance electrode material for supercapacitor applications. Field emission scanning electron microscopy (FESEM) analysis confirmed that Ag-NiFe₂O₄ nanoparticles were uniformly dispersed on the GnPs surface through functional groups, creating a synergistic effect that enhanced electrochemical properties. The incorporation of Ag-NiFe₂O₄ significantly improved the specific capacitance and charge storage capacity of the composite material. The maximum specific capacitance achieved was 913 F/g, with the ternary Ag-NiFe₂O₄ -GnPs composite outperforming pristine NiFe₂O₄ and Ag-NiFe₂O₄ at a scan rate of 10 mV/s. The electrochemical performance was influenced by key factors such as the GnPs content, electrode configuration, electrolyte type, and operating temperature. At the highest scan rate of 100 mV/s, shown in Fig. 5, the C<sub>sp</sub> values decreased to 319 F/g, 230 F/g, and 185 F/g for graphene-doped Ag-NFO, Ag-doped NFO, and NFO, respectively. These findings highlight the potential of Ag-NiFe₂O₄ - GnPs composites to replace conventional electrode materials in supercapacitors, paving the way for sustainable and high-performance energy storage systems.</div></div>","PeriodicalId":11266,"journal":{"name":"Diamond and Related Materials","volume":"155 ","pages":"Article 112264"},"PeriodicalIF":4.3,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143791367","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}
Veronica Siwalima , Joseph Y.N. Philip , Joel Nobert
{"title":"Synthesis of N-doped multi-walled carbon nanotubes derived from plastic waste for adsorption of Pb2+ ions in aqueous solutions","authors":"Veronica Siwalima , Joseph Y.N. Philip , Joel Nobert","doi":"10.1016/j.diamond.2025.112266","DOIUrl":"10.1016/j.diamond.2025.112266","url":null,"abstract":"<div><div>In this research multi-walled carbon nanotubes (MWCNTs) and nitrogen-doped multi-walled carbon nanotubes (N-MWCNTs) adsorbents were synthesized using polypropylene plastic as the carbon precursor, with melamine serving as the nitrogen source. A two-stage chemical vapour deposition (CCVD) method was employed for the pyrolysis of polypropylene, utilizing a nickel catalyst supported by CaCO<sub>3</sub>. Results showed that the nitrogen is successfully doped on N-MWCNTs as the surface is composed of nitrogen-containing groups, leading to the decrease in the carbon nanotube's outer diameter from 22.9 nm to 21.2 nm, an increase in crystallinity index from 81.40 to 83.19, an increase in specific surface area from 46.6 m<sup>2</sup> g<sup>−1</sup> to 76 m<sup>2</sup> g<sup>−1</sup>, and an increase in pore volume from 0.09 cm<sup>3</sup> g<sup>−1</sup> to 0.18 cm<sup>3</sup> g<sup>−1</sup>, enhancing their potential for adsorption applications. MWCNTs and N-MWCNTs were applied in the removal of Pb<sup>2+</sup> ions from wastewater and the highest removal efficiency was 88.1 % in N-MWCNTs compared to 80 % in MWCNTS. The optimum conditions of pH 5, an initial concentration of 1 mg L<sup>−1</sup>, and an adsorbent dose of 0.005 g were used. Langmuir isotherm provided a better fit for the adsorption data with maximum monolayer coverage (q<sub>o</sub>) of 7.52 mg g<sup>−1</sup> for MWCNTs and 8.91 mg g<sup>−1</sup> for N-MWCNTs. The adsorption process followed pseudo-second-order kinetics, indicating that chemical adsorption, involving electron exchange or sharing, is the dominant mechanism for MWCNTs and N-MWCNTs.</div></div>","PeriodicalId":11266,"journal":{"name":"Diamond and Related Materials","volume":"155 ","pages":"Article 112266"},"PeriodicalIF":4.3,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143777046","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":"Outside Front Cover - Journal name, Cover image, Volume issue details, ISSN, Cover Date, Elsevier Logo and Society Logo if required","authors":"","doi":"10.1016/S0925-9635(25)00365-6","DOIUrl":"10.1016/S0925-9635(25)00365-6","url":null,"abstract":"","PeriodicalId":11266,"journal":{"name":"Diamond and Related Materials","volume":"154 ","pages":"Article 112308"},"PeriodicalIF":4.3,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143839549","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}