Journal of Science: Advanced Materials and Devices最新文献

{"title":"Gas phase alloyed crystalline S–Se dielectrics with high ionic mobility","authors":"Pradyumna Kumar Chand ,&nbsp;Radha Raman ,&nbsp;Zhi-Long Yen ,&nbsp;Ian Daniell Santos ,&nbsp;Wei-Ssu Liao ,&nbsp;Ya-Ping Hsieh ,&nbsp;Mario Hofmann","doi":"10.1016/j.jsamd.2024.100763","DOIUrl":"https://doi.org/10.1016/j.jsamd.2024.100763","url":null,"abstract":"<div><p>The advancement of future electronic devices necessitates dielectric materials with enhanced compositional complexity and improved capabilities. We here demonstrate a gas-phase alloying approach that yields ultrathin and crystalline dielectrics with attractive properties for the integration into electronics. A surface-selective deposition process was shown to produce sulfur (S) and selenium (Se) alloys with large-scale uniformity. Through combination of experimental diffraction analysis and materials modeling, we establish the crystallinity of the alloy with a modified lattice structure compared to the host materials. The resulting lattice arrangement endows the alloy dielectric with high ionic mobility as validated by electrochemical impedance spectroscopy. Leveraging this innovative feature, we fabricate memristive devices exhibiting promising performance characteristics. Our findings demonstrate the feasibility of utilizing gas-phase alloying to engineer dielectrics with superior properties and functionality for future device integration.</p></div>","PeriodicalId":17219,"journal":{"name":"Journal of Science: Advanced Materials and Devices","volume":"9 3","pages":"Article 100763"},"PeriodicalIF":6.7,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2468217924000947/pdfft?md5=2e2390255e9e259672a7b80db97bfb4f&pid=1-s2.0-S2468217924000947-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141594079","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Construction of broad-spectrum photocatalyst films through interface engineering: Orchestrating Bi nanoparticles in TiO2/BiVO4 Z-scheme heterojunctions","authors":"Yuan-Chang Liang,&nbsp;Chih-Chen Kuo","doi":"10.1016/j.jsamd.2024.100764","DOIUrl":"https://doi.org/10.1016/j.jsamd.2024.100764","url":null,"abstract":"<div><p>We successfully synthesized three-layered photocatalysts by modifying Bi nanoparticles on TiO₂/BiVO₄ bilayer composite films through a sol-gel process and sputtering. When exposed to ambient air, the surface of the prepared Bi nanoparticles oxidizes to form an amorphous ultra-thin Bi₂O₃ out layer. Under light exposure, this layer is reduced to metallic Bi, thanks to the band alignment between the Bi nanoparticles and TiO₂/BiVO₄ Z-scheme composite. The addition of Bi nanoparticles in the composite films improves visible-light absorption by the surface plasmon resonance (SPR), which contributes to the hot electron and enhances the photocatalytic characteristics. By constructing effective TiO₂/BiVO₄ Z-scheme heterostructures to facilitate photoinduced electron-hole pair separation and prevent recombination, Bi nanoparticles can efficiently capture photons and enhance the photocatalytic efficiency of semiconductors through the SPR effect. Optimizing the content of Bi nanoparticles decorated on the TiO₂/BiVO₄ Z-scheme composite film is a promising approach for designing a highly efficient photocatalyst, as evidenced by the performance of photoelectrochemical properties and RhB photodegradation ability.</p></div>","PeriodicalId":17219,"journal":{"name":"Journal of Science: Advanced Materials and Devices","volume":"9 3","pages":"Article 100764"},"PeriodicalIF":6.7,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2468217924000959/pdfft?md5=5d214488e862e1028e43ad2d8c623a45&pid=1-s2.0-S2468217924000959-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141606008","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Partially oxidized polyvinyl alcohol + functionalized water soluble multiwalled carbon nanotubes: A new conductive nanocomposite material with promising implications for neuroregeneration","authors":"Elena Stocco ,&nbsp;Silvia Barbon ,&nbsp;Ludovica Ceroni ,&nbsp;Marta Confalonieri ,&nbsp;Giada Pulzato ,&nbsp;Samuel Pressi ,&nbsp;Alice D'Osualdo ,&nbsp;Marta Contran ,&nbsp;Rafael Boscolo-Berto ,&nbsp;Cesare Tiengo ,&nbsp;Silvia Todros ,&nbsp;Piero G. Pavan ,&nbsp;Veronica Macchi ,&nbsp;Raffaele De Caro ,&nbsp;Laura Calvillo ,&nbsp;Enzo Menna ,&nbsp;Andrea Porzionato","doi":"10.1016/j.jsamd.2024.100762","DOIUrl":"10.1016/j.jsamd.2024.100762","url":null,"abstract":"<div><p>Carbon nanotubes (CNT) are promising electroconductive nano-scale materials for neuroregeneration. Herein, we report on a new electroconductive composite scaffold made of the polymer 1% oxidized polyvinyl alcohol (OxPVA) combined with functionalized water soluble multiwalled CNT (OxPVA + MWCNT-S) (diazotization reaction). Preliminarily, MWCNT-S were characterized to evaluate the reaction outcome, the degree of functionalization and the dispersibility in water. Thereafter, OxPVA + MWCNT-S nanocomposite membranes were fabricated and analyzed for physicochemical properties (Raman spectroscopy, thermal decomposition, calorimetric properties, electroconductivity), macroscopic appearance and ultrastructure, mechanical behavior, <em>in vitro</em> cytotoxicity and <em>in vivo</em> biocompatibility. In parallel, OxPVA + MWCNT-S membranes with a linear pattern were also developed and analyzed for interaction with SH-SY5Y cells. Compared to OxPVA, the presence of MWCNT-S (only 0.016 wt%) significantly increased polymer conductivity and imparted a certain porosity without altering mechanical behaviour, as corroborated by uniaxial tensile tests. Neither cytotoxicity nor local signs of inflammation were detected <em>in vitro</em> and after subcutaneous implantation (14 and 42 days), proving composite material biocompatibility. OxPVA + MWCNT-S nanocomposite revealed as promising for future electroconductive conduits free from toxic effects amenable to CNT agglomeration within the polymer. Ideally, nerve lesions with wide gaps, may be effectively supported by those “active” devices, overcoming limitations of the available ones. Despite preliminary data, the presence of a linear pattern confirmed to have a beneficial effect over the scaffold/cells interaction.</p></div>","PeriodicalId":17219,"journal":{"name":"Journal of Science: Advanced Materials and Devices","volume":"9 3","pages":"Article 100762"},"PeriodicalIF":6.7,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2468217924000935/pdfft?md5=2199d2409ff7b8da052c7fe640acc250&pid=1-s2.0-S2468217924000935-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141549683","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Micrometric thermal electronic nose able to detect and quantify individual gases in a mixture","authors":"Matteo Tonezzer ,&nbsp;Michele Ricci ,&nbsp;Nguyen X. Thai ,&nbsp;Hugo Nguyen ,&nbsp;Nguyen V. Duy ,&nbsp;Nguyen D. Hoa","doi":"10.1016/j.jsamd.2024.100760","DOIUrl":"https://doi.org/10.1016/j.jsamd.2024.100760","url":null,"abstract":"<div><p>Recent urbanization and environmental problems urge for networks of sensors that can monitor air quality. Small, inexpensive, and smart sensors are one of the key components enabling the realization of such networks. Chemoresistive sensors are the ideal candidate, but they greatly lack selectivity, and for this reason, they are usually combined in arrays to create electronic noses, whose dimensions, however, make them not miniaturizable and cannot be integrated into portable devices. To overcome this inconvenience, we present a thermal electronic nose consisting of identical resistive sensors working at different temperatures so that the whole device is simple to make and tiny. The device contains two sensor arrays based on tin oxide nanowires decorated with Ag and Pt nanoparticles, respectively. The five sensors in each array are identical, but their response is differentiated by different temperatures locally generated by an on-chip integrated heater. This innovative approach allows the tiny array of five sensors together with the integrated heater to occupy only approximately 50 × 200 μm² and consume only 120 μW. The tiny and portable device can estimate the concentration of H₂ and NH₃ in a mixture with a root mean square error of 6.1 ppm and 13.3 ppm, respectively, and it still works well after two months. The performance analysis of the double partial least squares regression used for concentration estimation also allows for feedback on which sensors are the most sensitive to which gas so that the electronic nose can be engineered for specific applications using the most suitable sensors. The size of the thermal electronic nose allows it to be integrated into portable and wearable devices, and its performance makes it suitable for any gas detection application. For example, a smartphone with an integrated sensor could carry out breath analysis and act as medical pre-screening or be used to evaluate the freshness of agri-food products in a rapid and non-invasive way.</p></div>","PeriodicalId":17219,"journal":{"name":"Journal of Science: Advanced Materials and Devices","volume":"9 3","pages":"Article 100760"},"PeriodicalIF":6.7,"publicationDate":"2024-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2468217924000911/pdfft?md5=1dc070a65bdc12edc6a81917ef96cf82&pid=1-s2.0-S2468217924000911-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141594080","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"CPP10-targeted photoactivatable MOF nanosystem for combined photodynamic Therapy−Chemotherapy of cancer","authors":"Jiahui Kong,&nbsp;Mengru Cai,&nbsp;Rongyue Zhu,&nbsp;Yongqiang Zhang,&nbsp;Yuji Du,&nbsp;Xiaohong Jing,&nbsp;Yufei Sun,&nbsp;Rongrong Chang,&nbsp;Changhai Qu,&nbsp;Xiaoxv Dong,&nbsp;Jian Ni,&nbsp;Xingbin Yin","doi":"10.1016/j.jsamd.2024.100761","DOIUrl":"https://doi.org/10.1016/j.jsamd.2024.100761","url":null,"abstract":"<div><p>The annual prevalence of gastric cancer has increased in recent years. Curcumin (CUR) has shown great potential in the treatment of gastric cancer; however, its low bioavailability and poor efficacy hinder its widespread clinical application. Additionally, CUR has been found to be excellent photosensitizer in photodynamic therapy. In this study, the Fe-based metal-organic framework (MOF) Fe Tetrakis (4-carboxyphenyl) porphyrin (Fe-TCPP，FT) was used as a photosensitizer and mononuclear agent. The natural anti-tumor active ingredient CUR was loaded as both a chemotherapeutic agent and photosensitizer to form the nanoparticles CUR@FT (CF). Finally, a cell-penetrating peptide (CPP10) was modified on the surface of the nanoparticles to construct a drug delivery system (named CPP10-PEG@CUR@FT, CCF) that could actively target tumor cells while exerting a synergistic therapeutic effect of chemotherapy and photodynamic therapy. This can improve the efficacy of CUR as a chemotherapeutic drug or photosensitizer, and the high drug load and pH sensitivity of FT nanoparticles provide an excellent carrier for the efficient delivery of CUR. The polyethene glycol (PEG)-conjugated CPP10 (PEG-CPP10) coating allows nanoparticles to specifically target gastric cancer cells, significantly improving the absorption of nanoparticles in vivo and in vitro and improving biosafety. We evaluated the thermal stability, drug loading capacity, and safety of FT as a drug delivery vehicle. We also assessed the in vitro photodynamic performance and toxicity of various nanoparticles and the targeting and biocompatibility of CPP10-PEG@CUR@FT. CPP10-PEG@CUR@FT could specifically target tumor cells, and its effect on killing gastric cancer cells (MKN45) under light was much stronger than that of free CUR. Its toxicity and side effects to other organs and tissues are low, offering good biosafety. The experimental results showed that FT and CUR exerted synergistic effects on photodynamic therapy and chemotherapy. In summary, our novel CUR-loaded targeted nano drug delivery system offers significant advantages by combining photodynamic therapy and chemotherapy for tumor treatment. This approach introduces a new concept for integrating chemotherapy, photodynamic therapy and targeted drug delivery, potentially providing a new strategy for the clinical treatment of gastric cancer.</p></div>","PeriodicalId":17219,"journal":{"name":"Journal of Science: Advanced Materials and Devices","volume":"9 3","pages":"Article 100761"},"PeriodicalIF":6.7,"publicationDate":"2024-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2468217924000923/pdfft?md5=5270e2b1be4d104451eb0ca533fc1b29&pid=1-s2.0-S2468217924000923-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141539218","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ultrasound assisted green synthesis of silver nanoparticles stabilized by chitosan polymers: Investigation of its therapeutic application in diarrhea","authors":"Lin Wang ,&nbsp;Lei Qiao ,&nbsp;Yuzhi Liu ,&nbsp;Fengyue Li ,&nbsp;Attalla F. El-kott ,&nbsp;Mohammed A. AlShehri ,&nbsp;Kareem Morsy","doi":"10.1016/j.jsamd.2024.100759","DOIUrl":"https://doi.org/10.1016/j.jsamd.2024.100759","url":null,"abstract":"<div><p>The current investigation aims to study the bio route preparation of chitosan capped-silver nanoparticles using aqueous flower extract of the <em>Achillea ptarmica</em> plant. The biosynthesized silver nanoparticles/chitosan (Ag NPs@CHI) were characterized by various spectroscopic techniques. The creation of Ag nanoparticles over the chitosan was initially determined by the presence of a single broad peak at 545 nm that was recorded by the UV–Vis spectrum. The presence of poly-dispersity, spherical shape and nanosizes in the Ag NPs@CHI were verified by the TEM and SEM pictures. The purity and crystalline nature of the prepared Ag NPs@CHI were confirmed by XRD analysis. <em>In vivo</em>, Ag NPs@CHI decreased the inflammatory cells presence in the colon and ileum, lowered the levels of IL-17A, IL-1β, IL-6, and TNF-α, raised the levels of IL-10 and IL-4 in colon tissues, enhanced acetate and propionate production. The findings revealed that Ag NPs@CHI have the potential to boost intestinal structure restoration, decrease levels of inflammatory cytokines and enhance short-chain fatty acid (SCFA) levels. Our research demonstrated that Ag NPs@CHI can safeguard the intestinal barrier by upregulating the expression of Claudin-1 and Occludin. Furthermore, silver nanoparticles suppressed the MAPK signaling pathway to ameliorate the inflammatory condition. Following the completion of clinical trials, these novel nanoparticles could serve as a promising new treatment for diarrhea in humans.</p></div>","PeriodicalId":17219,"journal":{"name":"Journal of Science: Advanced Materials and Devices","volume":"9 3","pages":"Article 100759"},"PeriodicalIF":6.7,"publicationDate":"2024-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S246821792400090X/pdfft?md5=e19e0390d66f04094da6eca0a255b71a&pid=1-s2.0-S246821792400090X-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141594078","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhancement of the microwave absorption properties of the SrFe12O19@Fe3O4@rGO composite material","authors":"Tran Thi Viet Nga ,&nbsp;Nguyen Thi Lan ,&nbsp;To Thanh Loan ,&nbsp;Tran Quang Dat","doi":"10.1016/j.jsamd.2024.100758","DOIUrl":"https://doi.org/10.1016/j.jsamd.2024.100758","url":null,"abstract":"<div><p>In this work, graphene oxide (GO) was prepared via the Hummers’ method, whereas SrFe₁₂O₁₉, SrFe₁₂O₁₉@Fe₃O₄, and SrFe₁₂O₁₉@Fe₃O₄@rGO were fabricated using the hydrothermal techniques. The samples' phase structure, surface morphology, magnetic properties, and electromagnetic wave absorption characteristics were studied and compared. Findings show that the Fe₃O₄ particles adhered to the surface of the SrFe₁₂O₁₉ hexagonal plates, and the combination of SrFe₁₂O₁₉@Fe₃O₄ foam flakes and two-dimensional graphene rGO could enhance the absorption electromagnetic wave performance. The composite SrFe₁₂O₁₉@Fe₃O₄@rGO sample exhibited an ideal impedance matching within the frequency <em>f</em> range of 11 GHz–12.4 GHz. The minimum reflection loss reached −62.3 dB at 12.2 GHz with a thickness of 2 mm. With a thickness of 2 mm, the effective absorption bandwidth obtained the value of −20 dB, covering a range of 9.3 GHz. The composite SrFe₁₂O₁₉@Fe₃O₄@rGO sample, which shows the highest performance both in reflectivity and bandwidth, can find potential application in microwave absorptions.</p></div>","PeriodicalId":17219,"journal":{"name":"Journal of Science: Advanced Materials and Devices","volume":"9 3","pages":"Article 100758"},"PeriodicalIF":6.7,"publicationDate":"2024-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2468217924000893/pdfft?md5=9721a26c61f0f94c1bab48ffca17ccf3&pid=1-s2.0-S2468217924000893-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141486008","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Silver nanoparticles stabilized by chitosan-polyvinyl alcohol polymers mediated by Pistacia extract for treatment of functional dyspepsia and gastric cancer","authors":"Cui Jin ,&nbsp;Zhongxin Zhang ,&nbsp;Xiaopei Li","doi":"10.1016/j.jsamd.2024.100757","DOIUrl":"10.1016/j.jsamd.2024.100757","url":null,"abstract":"<div><p>The impact of the nanoparticles on the dyspepsia mice gut microbiota is evaluated through the utilization of the 16S rRNA technique. Various methods were employed to characterize the NPs. In the textile, culinary, paper, leather, and printing sectors, synthetic dyes are frequently employed as coloring agents. Because these dye molecules are harmful to both the environment and living things, it is difficult to remove them sustainably. Here, we have produced nanoparticles embedded in chitosan-polyvinyl alcohol hydrogel (CS-PVA) by using bark's <em>Pistacia</em> under ultrasonic irradiation. The reduction of Ag ⁺ ions into Ag⁰ NPs was detected by a visual change in the colors. UV–Vis analysis indicated that the characteristic SPR band appeared near ∼440–450 nm. UV/Vis, EDX-elemental mapping, SEM, TEM, ICP-OES, and XRD analysis were applied to characterize the Ag NPs/CS-PVA nanocomposite. The recent study focused on the cellular and molecular aspects. The MTT assay was conducted for 48 h to evaluate the anti-human gastric cancer and cytotoxicity efficacies of the treated cells with nanocomposite. The assessment was performed on normal (HUVEC) and gastric cancer cells, namely MKN45 and NCI–N87. The IC₅₀ values of nanocomposite against MKN45 and NCI–N87 were 180 and 151 μg/mL, respectively. The dose-dependent reduction in malignant gastric cell viability was observed in the nanocomposite presence. Furthermore, the nanocomposite induced cell apoptosis by 40–50%, leading to an increase in the expression of pro-apoptotic markers (Bax and cleaved caspase-8) and a decrease in the expression of the anti-apoptotic marker, Bcl-2. Furthermore, the nanocomposite showed inhibitory effects on colony formation. Our results indicate that the nanocomposite can increase p53 expression and decrease the expression of STAT3 in treated cells. This indicates that p53 and STAT3 play crucial roles in the biological effects induced by the extract in human gastric carcinoma cells. The data from the gut microbiome suggested that nanocomposites have the ability to control the rebalancing of homeostasis and microbiome composition by decreasing the levels of harmful bacteria, and at the same time, increasing the levels of beneficial bacteria. Following the introduction of nanocomposite, there was an observed rise in the levels of gastrointestinal hormones in the serum, including gastrin and motilin, while the levels of vasoactive intestinal peptide decreased. The application of nanocomposite led to an improvement in gastrointestinal movement, encompassing a rise in the rate of transit through the small intestine and the rate of gastric emptying. These findings offer that the Ag NPs/CS-PVA nanocomposite could be a promising anticancer treatment for functional dyspepsia and gastric cancer.</p></div>","PeriodicalId":17219,"journal":{"name":"Journal of Science: Advanced Materials and Devices","volume":"9 3","pages":"Article 100757"},"PeriodicalIF":6.7,"publicationDate":"2024-06-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2468217924000881/pdfft?md5=537d74af50bbd63b42139b5301429750&pid=1-s2.0-S2468217924000881-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141415104","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Adsorption of dimethylaluminum isopropoxide (DMAI) on the Al2O3 surface: A machine-learning potential study","authors":"Miso Kim,&nbsp;Sehee Kim,&nbsp;Bonggeun Shong","doi":"10.1016/j.jsamd.2024.100754","DOIUrl":"10.1016/j.jsamd.2024.100754","url":null,"abstract":"<div><p>Dimethylaluminum isopropoxide (DMAI) is attracting attention as an alternative precursor for atomic layer deposition (ALD) of aluminum oxide (Al₂O₃). However, the surface chemical reaction mechanisms of DMAI during ALD regarding its dimeric structure under vacuum deposition process conditions has yet to be clear. In this work, the adsorption mechanism of dimeric and monomeric DMAI on a fully hydroxylated Al₂O₃ surface is studied using machine-learning potential (MLP) calculations. The initial adsorption of DMAI appears facile and would result in the coexistence of both methyl and isopropoxy ligands on the surface. The reactivity of DMAI is smaller than that of TMA, owing to the propensity of DMAI to adopt a dimeric form. Especially when the substrate is partially covered by other adsorbate species, the large molecular size and low reactivity of dimeric DMAI considerably hinder its reactivity toward surface adsorption. Current results are in good correspondence with the previous experimental results, where lower growth per cycle (GPC) and higher selectivity in area-selective ALD (AS-ALD) could be observed by using DMAI than compared to those of TMA processes.</p></div>","PeriodicalId":17219,"journal":{"name":"Journal of Science: Advanced Materials and Devices","volume":"9 3","pages":"Article 100754"},"PeriodicalIF":8.0,"publicationDate":"2024-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2468217924000856/pdfft?md5=9cbdef6a50b4b9595b5b7045893dbb76&pid=1-s2.0-S2468217924000856-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141276431","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Giant magnetocaloric effect and hysteresis loss in MnxFe2-xP0.5Si0.5 (0.7 ≤ x ≤ 1.2) microwires at ambient temperatures","authors":"Lin Luo ,&nbsp;Hongxian Shen ,&nbsp;Lunyong Zhang ,&nbsp;Yongjiang Huang ,&nbsp;Jianfei Sun ,&nbsp;Manh-Huong Phan","doi":"10.1016/j.jsamd.2024.100756","DOIUrl":"https://doi.org/10.1016/j.jsamd.2024.100756","url":null,"abstract":"<div><p>Magnetocaloric microwires are very promising for energy-efficient magnetic refrigeration in micro electromechanical systems (MEMS) and nano electromechanical systems (NEMS). Creating microwires that exhibit large magnetocaloric effects around room temperature represents an important but challenging task. Here, we report a tunable giant magnetocaloric effect around room temperature in Mn_<em>x</em>Fe_2-<em>x</em>P_0.5Si_0.5 (0.7≤<em>x</em> ≤ 1.2) microwires by utilizing a melt-extraction technique paired with thermal treatment and chemical engineering. The isothermal magnetic entropy change (Δ<em>S</em>_iso) and Curie temperature (<em>T</em>_C) can be tuned by adjusting the Mn/Fe ratio. The <em>T</em>_C varies from 351 to 190 K as <em>x</em> increases from 0.8 to 1.2. Among the compositions investigated, the <em>x</em> = 0.9 sample shows the largest value of Δ<em>S</em>_iso = 18.3 J kg⁻¹ K⁻¹ for a field change of 5 T around 300 K. After subtracting magnetic hysteresis loss, a large refrigerant capacity of ∼284.6 J kg⁻¹ is achieved. Our study paves a new pathway for the design of novel magnetocaloric microwires for active magnetic refrigeration at ambient temperatures.</p></div>","PeriodicalId":17219,"journal":{"name":"Journal of Science: Advanced Materials and Devices","volume":"9 3","pages":"Article 100756"},"PeriodicalIF":6.7,"publicationDate":"2024-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S246821792400087X/pdfft?md5=0b40fbf7b09e0267de44b2140750f617&pid=1-s2.0-S246821792400087X-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141486007","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}