Patrycja Koscielniak , Maria Sawicka , Ilya Sterin , Kamil Marcisz , Klaudia Kaniewska , Marcin Karbarz , Evgeny Katz , Oleh Smutok
{"title":"Cystamine-crosslinked and nanozyme decorated polyacrylic acid-based composite microgel of dual functionality: delivery and controlled doxorubicin release","authors":"Patrycja Koscielniak , Maria Sawicka , Ilya Sterin , Kamil Marcisz , Klaudia Kaniewska , Marcin Karbarz , Evgeny Katz , Oleh Smutok","doi":"10.1016/j.apsadv.2025.100773","DOIUrl":"10.1016/j.apsadv.2025.100773","url":null,"abstract":"<div><div>Developing new and improving existing systems for controlled drug release is one of the top tasks of biomaterials science nowadays. The current work aims to develop an efficiently controlled doxorubicin release system based on composite hydrogel formed by polyacrylic acid p(AA) cross-linked by <em>N,N</em>’-<em>bis</em>(acryloyl)cystamine (BAC). The formed p(AA-BAC) microgel provides a dual function as a pH-sensitive doxorubicin holding carrier as well as an immobilization matrix for covalent bonding of gold nanoparticles (AuNPs) via sulfur groups of cystamine derivative cross-linker. The immobilized AuNPs are characterized by nanozyme (glucose oxidase-like) activity able to generate the local pH decrease via gluconic acid production in the presence of glucose as a trigger. The resulting local pH decrease provides protonation of carboxylic groups of the p(AA-BAC) matrix resulting in diminished electrostatic attraction between the carrier and the positively charged payload, thus causing its release from the microgels. The structural and morphological characterization of the proposed p(AA-BAC)-AuNPs composite microgel was performed by SEM, AFM, TEM, FTIR, and other techniques. The kinetics of the triggered release of the self-fluorescent doxorubicin was tested by fluorimetry combined with confocal fluorescent analysis. It was demonstrated that the proposed composite p(AA-BAC)-AuNPs microgel could be used as a promising smart release system for releasing a positively charged payload in response to a locally elevated glucose level.</div></div>","PeriodicalId":34303,"journal":{"name":"Applied Surface Science Advances","volume":"27 ","pages":"Article 100773"},"PeriodicalIF":7.5,"publicationDate":"2025-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144090161","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Luisa Roxana Mandoc , Amalia Maria Soare , Giorgian Cosmin Ungureanu , Violeta-Carolina Niculescu , Mirela Irina Petreanu , Radu Dorin Andrei , Athanasios Tiliakos
{"title":"Optimal LiFePO4 ratios and loadings for LFP-type cathodes with Single-Ion Conducting Polymer Electrolyte (SICPE) membranes based on PBDT/LiFSI/MPPIFSI for lithium-ion batteries+","authors":"Luisa Roxana Mandoc , Amalia Maria Soare , Giorgian Cosmin Ungureanu , Violeta-Carolina Niculescu , Mirela Irina Petreanu , Radu Dorin Andrei , Athanasios Tiliakos","doi":"10.1016/j.apsadv.2025.100772","DOIUrl":"10.1016/j.apsadv.2025.100772","url":null,"abstract":"<div><div>LiFePO<sub>4</sub> composite cathodes based on LFP, carbon black, and PVDF were prepared with different mass percentages and loadings of the active material, and integrated in CR2032 cells using a Single-Ion Conducting Polymer Electrolyte (SICPE) membrane, alternatively known as Solid Molecular Ionic Composite Electrolyte (SMICE), based on a PBDT/LiFSI/MPPIFSI Molecular Ionic Composite (MIC). The assembled Li-ion battery cells were subjected to a series of tests to gauge their performance. The LFP|SMICE cathodes with a compositional ratio of 60 % and a loading of 1.1 mg cm<sup>–2</sup> in active material displayed the optimal performance, reaching 126 mAh g<sup>–1</sup> at the C/10 current rate, and 93 mAh g<sup>–1</sup> at the 1C current rate, presenting a capacity retention of 90.77 % by the end of the 555th cycle. Our work highlights the potential of combining LFP-type cathodes with single-ion conducting polymer electrolytes to increase the stability and performance of lithium-ion batteries while mitigating the safety issues associated with non-solid electrolytes, and determines the loadings and compositional ratios of LFP in the composite cathodes that present the optimal results in conjunction with SMICE.</div></div>","PeriodicalId":34303,"journal":{"name":"Applied Surface Science Advances","volume":"27 ","pages":"Article 100772"},"PeriodicalIF":7.5,"publicationDate":"2025-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144090162","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Tetiana Loskutova , Michael Scheffler , Vitalii Ivanov , Manja Krueger , Nadiia Kharchenko , Volodymyr Taran , Michal Hatala , Myroslav Karpets , Yaroslav Stelmakh , Georg Hasemann
{"title":"Influence of diffusion siliconizing and boron–siliconizing in chlorine-containing environments on the structure, composition, and protective properties of TZM molybdenum alloy","authors":"Tetiana Loskutova , Michael Scheffler , Vitalii Ivanov , Manja Krueger , Nadiia Kharchenko , Volodymyr Taran , Michal Hatala , Myroslav Karpets , Yaroslav Stelmakh , Georg Hasemann","doi":"10.1016/j.apsadv.2025.100769","DOIUrl":"10.1016/j.apsadv.2025.100769","url":null,"abstract":"<div><div>Theoretical calculations of the physicochemical conditions of molybdenum-based alloys' siliconizing and boron–siliconizing processes were carried out. Based on the obtained data, the phase composition and its quantitative ratio in the coatings were predicted. The theoretical calculations were experimentally confirmed. The coatings' microstructure, phase, and chemical composition obtained by siliconizing and boron–siliconizing TZM molybdenum alloy in a chlorine medium were studied. The thickness and microhardness of protective coatings are determined. The heat resistance of the obtained coatings in an air atmosphere at 800⁰C for 48 hours was investigated. A recommendation for further use is provided.</div></div>","PeriodicalId":34303,"journal":{"name":"Applied Surface Science Advances","volume":"27 ","pages":"Article 100769"},"PeriodicalIF":7.5,"publicationDate":"2025-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143947050","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Remy Viennet, Virginie Moutarlier, Nicolas Rouge, Jean-Yves Hihn
{"title":"Etching titanium with 70 % H2SO4: Effects on morphology, composition, and corrosion resistance of anodic films","authors":"Remy Viennet, Virginie Moutarlier, Nicolas Rouge, Jean-Yves Hihn","doi":"10.1016/j.apsadv.2025.100767","DOIUrl":"10.1016/j.apsadv.2025.100767","url":null,"abstract":"<div><div>Efficient surface preparation is crucial for enhancing the corrosion resistance of titanium before anodizing. This study explores the use of concentrated sulfuric acid (70 % H₂SO₄) for titanium surface preparation under various temperatures (20 °C and 50 °C) and immersion times (15 and 30 min). Surface modifications in morphology and composition are analyzed using SEM, GDOES, XRD, and XPS techniques. Mild etching conditions (low temperatures and short durations) have been proven to be insufficient for removing surface contaminants, such as titanium carbide. On the contrary, harsher conditions (extended immersion times or/and higher temperatures) effectively eliminate impurities but result in hydrogenation of the titanium surface. In this case, a titanium hydride layer (TiH<sub>2</sub>) appears on the surface, modifying its morphology and roughness. On this occasion, the combination of XRD and GDOES techniques proves to be effective in revealing the presence of hydrides. Moreover, hydrogenation significantly increases with immersion time and temperature. Eventually, the impact of etching conditions on anodic film corrosion properties is also evaluated by EIS measurements. The study highlights that performances of anodic films are strongly influenced by the etching parameters. Indeed, titanium hydride layers can adversely affect corrosion resistance of anodic films. Therefore, to ensure optimal results, etching conditions must strike a balance between thorough cleaning and minimizing hydrogenation, thereby preserving the corrosion resistance of anodic films.</div></div>","PeriodicalId":34303,"journal":{"name":"Applied Surface Science Advances","volume":"27 ","pages":"Article 100767"},"PeriodicalIF":7.5,"publicationDate":"2025-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143937735","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Coating-by-design: design a high-temperature oxidation and corrosion resistant Zr-doped MCrAlY coating fabricated by magnetron sputtering","authors":"Shen Tao , Hui Peng , Anqin Zhang , Hongbo Guo","doi":"10.1016/j.apsadv.2025.100766","DOIUrl":"10.1016/j.apsadv.2025.100766","url":null,"abstract":"<div><div>Here, we propose a rapid coating design and verification approach via magnetron sputtering, which is first applied to Zr-doped MCrAlY coatings. By utilising the compositional gradient of the as-deposited coatings, ten candidates with varying Zr contents were evaluated. Among them, the coating with 0.15 wt.% Zr exhibited the best oxidation and corrosion resistance. Results show that moderate Zr doping promotes the θ-Al<sub>2</sub>O<sub>3</sub> to α-Al<sub>2</sub>O<sub>3</sub> transformation and delays the β to γ/γ′ phase transition, leading to the formation of a dense and smooth oxide scale. However, EBSD analysis reveals that increasing Zr content coarsens the grain size, and excessive Zr accelerates Al depletion and promotes spinel formation. During oxidation, a semicoherent γ/γ′ to α-Al<sub>2</sub>O<sub>3</sub> interface is formed, whereas in corrosion-tested samples, the β-NiAl to α-Al<sub>2</sub>O<sub>3</sub> interface becomes incoherent, weakening interfacial bonding. Nevertheless, Zr diffusion from the coating into the thermally grown oxide (TGO) forms Zr-rich bands, which significantly inhibit Al outward diffusion. Thermo-Calc simulations indicate that the volume fraction of β-NiAl at 1100 °C (low Al content β-NiAl) is much higher than at 900 °C (high Al content β-NiAl), and that Zr has little effect on the overall phase distribution. Coatings prepared via arc ion plating further confirm that Zr-doped coatings outperform Zr-free ones in cyclic oxidation and corrosion resistance.</div></div>","PeriodicalId":34303,"journal":{"name":"Applied Surface Science Advances","volume":"27 ","pages":"Article 100766"},"PeriodicalIF":7.5,"publicationDate":"2025-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143931712","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Regina Maria Chiechio , Antonino Scandurra , Riccardo Reitano , Paolo Musumeci , Maria Grazia Grimaldi , Annalinda Contino , Giuseppe Maccarrone , Valerie Marchi , Ludovica Maugeri , Salvatore Petralia , Francesco Ruffino
{"title":"Quantum fluorescent gold nanoclusters for PCR-free ultrasensitive DNA detection","authors":"Regina Maria Chiechio , Antonino Scandurra , Riccardo Reitano , Paolo Musumeci , Maria Grazia Grimaldi , Annalinda Contino , Giuseppe Maccarrone , Valerie Marchi , Ludovica Maugeri , Salvatore Petralia , Francesco Ruffino","doi":"10.1016/j.apsadv.2025.100762","DOIUrl":"10.1016/j.apsadv.2025.100762","url":null,"abstract":"<div><div>Gold nanoclusters (AuNCs) have emerged as promising tools for biomedical and environmental applications due to their photoluminescence, biocompatibility, and molecule-like electronic structure. This study presents a novel AuNC-based sensor platform, characterized by eco-friendly synthesis, label-free functionality, and ultrasensitivity for biomolecular detection. AuNCs were synthesized using a green chemistry approach without toxic solvents, yielding strong optical properties with an absorbance peak at 400 nm and emission at 600 nm. Functionalization with thiolated single-stranded DNA (ssDNA) enabled fluorescence-based detection of specific DNA sequences with a limit of detection in the attomolar range. The sensor demonstrated high specificity, distinguishing target DNA from non-specific sequences in both buffer solutions and complex biological matrices, including blood. The modular design allows adaptation to detect various biomolecules by incorporating specific aptamers. This versatile, cost-effective platform combines eco-friendly synthesis, high sensitivity, and specificity, offering significant potential for advanced diagnostics and environmental monitoring in real-world settings.</div></div>","PeriodicalId":34303,"journal":{"name":"Applied Surface Science Advances","volume":"27 ","pages":""},"PeriodicalIF":7.5,"publicationDate":"2025-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143927639","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Haujin Salih , Maximilian Cieluch , Philipp L. Maack , Norbert Kazamer , Florian Wirkert , Ulrich Rost , Cemal Esen , Michael Brodmann
{"title":"Femtosecond laser-induced surface structuring of porous nickel substituting anodic catalyst layers for alkaline oxygen evolution reaction","authors":"Haujin Salih , Maximilian Cieluch , Philipp L. Maack , Norbert Kazamer , Florian Wirkert , Ulrich Rost , Cemal Esen , Michael Brodmann","doi":"10.1016/j.apsadv.2025.100756","DOIUrl":"10.1016/j.apsadv.2025.100756","url":null,"abstract":"<div><div>Femtosecond laser-induced nano structuring offers a novel approach to enhance the performance of porous transport layers (PTLs) in anion-exchange membrane water electrolysis. By applying ultrashort laser pulses to nickel felts, distinct surface morphologies were generated, including high-spatial-frequency laser-induced periodic surface structures (HSFL-LIPSS), irregular ablated surfaces, and hybrid structures. Surface area analysis revealed increases of up to 4-fold for LIPSS, 6-fold for hybrid structures (LIPSS+Ablation), and 9-fold for ablated surfaces compared to untreated fibers. Electrochemical testing showed reduced overpotentials for laser-treated samples, comparable to state-of-the-art electrodes despite the absence of catalyst layers. Overpotentials could be reduced by up to 6.5 % at 10 mA cm<sup>−2</sup> and by up to 9.6 % at 100 mA cm<sup>−2</sup> compared to the unprocessed felt. Notably, ablated structures, with the highest surface areas, exhibited microcavities that may entrap oxygen bubbles, limiting active site and reaction rates. The LIPSS structures demonstrated the lowest activation losses and highest current density (1.32 A cm⁻² at 2.0 V) due to their periodic morphology and enhanced electrolyte flow, representing a 17 % improvement at 2.0 V compared to the untreated felts. Moreover, Tafel slopes down to 66 mV dec<sup>−1</sup> denote a performant kinetic while oxidation charge measurements revealed pronounced peaks for laser-treated samples, with ablated surfaces achieving the highest charge of 16.76 ± 1.64 C cm⁻². Chronopotentiometry revealed the LIPSS structures showing the highest resistance to degradation among the structured samples.</div><div>These findings suggest femtosecond laser nano structuring as a promising method to improve PTL performance. Further application of catalyst layers could amplify the electrochemical efficiency of these advanced materials.</div></div>","PeriodicalId":34303,"journal":{"name":"Applied Surface Science Advances","volume":"27 ","pages":"Article 100756"},"PeriodicalIF":7.5,"publicationDate":"2025-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143922087","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Attila Forgács , Madalina Ranga , Andreea Ranga , László István Orosz , Geo Paul , Leonardo Marchese , Dániel Pércsi , Adél Len , Zoltán Dudás , Gergő Vecsei , Attila Csík , István Fábián , József Kalmár
{"title":"Pristine and cross-linked gelatin aerogels of pH-responsive hydration and swelling","authors":"Attila Forgács , Madalina Ranga , Andreea Ranga , László István Orosz , Geo Paul , Leonardo Marchese , Dániel Pércsi , Adél Len , Zoltán Dudás , Gergő Vecsei , Attila Csík , István Fábián , József Kalmár","doi":"10.1016/j.apsadv.2025.100765","DOIUrl":"10.1016/j.apsadv.2025.100765","url":null,"abstract":"<div><div>Protein aerogels, derived from natural sources such as plants and animals, are sustainable and biocompatible advanced materials with significant potential for applications in the environmental, food, and pharmaceutical industries. In this study, food-grade gelatin was used to produce highly porous aerogels. Gelatin was employed either in its native form or chemically cross-linked with glutaraldehyde (GTA). Hydrogels were synthesized through a simple sol-gel process, transferred to methanol, and then dried using supercritical CO<sub>2</sub> to obtain mesoporous aerogels. The chemical structure of the aerogels was characterized using solid-state nuclear magnetic resonance (ssNMR) and infrared (IR) spectroscopy methods. Their nanoscale morphologies were explored by scanning electron microscopy (SEM), N<sub>2</sub>-sorption porosimetry, and small-angle neutron scattering (SANS). The macroscopic water uptake and swelling of the gelatin aerogels were investigated at different pH values, while the corresponding nanoscale hydration and wetting mechanisms were explored using NMR relaxometry. Lastly, the drug loratadine was impregnated into the pure gelatin aerogel to assess its potential for drug delivery applications. The rate and mechanism of in vitro drug release exhibit a strong correlation with the pH-dependent swelling and dissolution of the aerogel. These findings suggest that pure gelatin aerogels are promising candidates for pH-sensitive oral drug delivery systems.</div></div>","PeriodicalId":34303,"journal":{"name":"Applied Surface Science Advances","volume":"27 ","pages":"Article 100765"},"PeriodicalIF":7.5,"publicationDate":"2025-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143922088","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yeongjun Yoon , Yunseo Choi , Yonggyun Bae , Jongsup Hong , Kyeounghak Kim
{"title":"Ni-based alloy catalysts for cost-effective hydrogen production from ammonia decomposition","authors":"Yeongjun Yoon , Yunseo Choi , Yonggyun Bae , Jongsup Hong , Kyeounghak Kim","doi":"10.1016/j.apsadv.2025.100759","DOIUrl":"10.1016/j.apsadv.2025.100759","url":null,"abstract":"<div><div>Due to its high hydrogen storage capacity and established infrastructure, ammonia (NH<sub>3</sub>) decomposition has been extensively investigated as a clean hydrogen production process. However, hydrogen production via ammonia decomposition faces various challenges. Although ruthenium (Ru) catalysts exhibit the highest activity for ammonia decomposition, their scarcity and high cost hinder commercial application. Consequently, nickel (Ni) catalysts have emerged as a potential alternative, owing to their cost-effectiveness and high activity. To further optimize Ni catalysts, developing Ni-based alloy catalysts with other metals is a promising solution. Herein, density functional theory (DFT) calculations are performed to elucidate the catalytic activity of 3d transition metals (Ni, Co, Cu, and Fe) and their promising alloys. The key reaction steps of overall ammonia decomposition are NH<sub>x</sub>‒H bond scission (NH<sub>x</sub>*→NH<sub>x-1</sub>*+H*) and N + N recombination (N*+N*→N<sub>2</sub>*). In particular, nitrogen adsorption energy (E<sub>ad</sub>(N)) serves as a descriptor for predicting the activation energies of key elementary steps, revealing a volcano-like relationship between experimental catalytic activity and DFT-calculated E<sub>ad</sub>(N). Additionally, we discover a strong correlation between d-band filling (f<sub>d</sub>) and E<sub>ad</sub>(N), establishing f<sub>d</sub> as an effective descriptor that not only predicts E<sub>ad</sub>(N) but also the catalytic activity of NH<sub>3</sub> decomposition. Our descriptor-based design principle identifies Ni<sub>0.64</sub>Fe<sub>0.36</sub> as a potentially effective and cost-efficient candidate for hydrogen production from ammonia, with experimental data demonstrating its superior performance compared to pure Ni. These findings offer valuable insights into the development of efficient, economically viable transition metal-based catalysts for hydrogen production through ammonia decomposition.</div></div>","PeriodicalId":34303,"journal":{"name":"Applied Surface Science Advances","volume":"27 ","pages":"Article 100759"},"PeriodicalIF":7.5,"publicationDate":"2025-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143921815","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Temperature-induced evolutions in critical point optical transitions in HfS2 investigated by spectroscopic ellipsometry","authors":"Qihang Zhang , Honggang Gu , Zhengfeng Guo , Shiyuan Liu","doi":"10.1016/j.apsadv.2025.100763","DOIUrl":"10.1016/j.apsadv.2025.100763","url":null,"abstract":"<div><div>A thorough understanding of the temperature-dependent optical properties and underlying physical mechanisms of a novel material is critical for the optimization of related optoelectronic devices. In this study, we comprehensively investigate the optical properties of the transition metal dichalcogenide HfS<sub>2</sub> over a broadband energy range of 0.75–5.91 eV with the temperatures changing from 100 K to 600 K by using the spectroscopic ellipsometry, critical point analysis, and first-principles calculations. The temperature-dependent dielectric functions are determined, and seven critical points (A–G) and their associated optical transitions are quantitatively revealed. We found that the central energies of these critical points exhibit temperature-induced blueshifts, consistent with the Varshni equation and Bose-Einstein model. The behavior of the critical points is significantly different as affected by thermal expansion and electron-phonon interactions of varying degrees. Due to the temperature-induced reversible phase transition of HfS<sub>2</sub>, critical points C and E exhibit dramatically increasing broadening and ultimately disappear. The locations of these optical transitions in the Brillouin zone and the involved carriers are further identified through energy band structure and projected density of states by combining the critical points analysis and first-principles calculations.</div></div>","PeriodicalId":34303,"journal":{"name":"Applied Surface Science Advances","volume":"27 ","pages":"Article 100763"},"PeriodicalIF":7.5,"publicationDate":"2025-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143922089","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}