Pub Date : 2024-06-17DOI: 10.1557/s43578-024-01368-8
Julia I. Salas, Sk Shamim Hasan Abir, Diego de Leon, Ignacio Serrato, Horacio Vasquez, Karen Lozano, M. Jasim Uddin
Triboelectric nanogenerators (TENGs) have received considerable attention as flexible and stretchable systems capable of harvesting energy and converting mechanical into electrical energy. This paper reports on Forcespinning-synthesized poly(vinylidene fluoride) (PVDF) and thermoplastic polyurethane (TPU) nanofiber (NF) membranes based TENG. To improve the TENG, the TPU NFs were decorated with multi-walled carbon nanotubes (MWCNT) functionalized with fluoride, amide, and carboxylic groups. The NF demonstrated a stronger interaction with the carboxylic-functionalized MWCNT (c-MWCNT). Furthermore, the c-MWCNT functionalized TPU/PVDF TENGs were evaluated by applying compressive force (30 psi) utilizing a pneumatic cylinder. The maximum alternating voltage, and current outputs were 158 V and 170 µA respectively. The TENG charging capacity for the samples dipped for 12 h in the c-MWCNT showed an ability to charge a 1 µF capacitor up to 3.03 V in 25 s of hand tapping, suggesting that the fabricated TENG has the capability to function as a self-charging flexible energy harvester.
Graphical abstract
三电纳米发电机（TENGs）作为能够收集能量并将机械能转化为电能的柔性可伸缩系统，已受到广泛关注。本文报告了基于 Forcespinning 合成的聚（偏二氟乙烯）（PVDF）和热塑性聚氨酯（TPU）纳米纤维（NF）膜的三电纳米发电机。为了改进 TENG，用氟化物、酰胺和羧基官能化的多壁碳纳米管（MWCNT）装饰了热塑性聚氨酯（TPU）纳米纤维膜。NF 与羧基官能化的多壁碳纳米管（c-MWCNT）的相互作用更强。此外，利用气缸施加压缩力（30 psi）对 c-MWCNT 功能化 TPU/PVDF TENG 进行了评估。最大交流电压和电流输出分别为 158 V 和 170 µA。在 c-MWCNT 中浸泡 12 小时的样品的 TENG 充电能力显示，在 25 秒的手动敲击时间内，1 µF 电容器的充电电压可达 3.03 V，这表明所制造的 TENG 具有作为自充电柔性能量收集器的能力。
{"title":"Energy harvesting with thermoplastic polyurethane nanofiber mat integrated with functionalized multiwalled carbon nanotubes","authors":"Julia I. Salas, Sk Shamim Hasan Abir, Diego de Leon, Ignacio Serrato, Horacio Vasquez, Karen Lozano, M. Jasim Uddin","doi":"10.1557/s43578-024-01368-8","DOIUrl":"https://doi.org/10.1557/s43578-024-01368-8","url":null,"abstract":"<p>Triboelectric nanogenerators (TENGs) have received considerable attention as flexible and stretchable systems capable of harvesting energy and converting mechanical into electrical energy. This paper reports on Forcespinning-synthesized poly(vinylidene fluoride) (PVDF) and thermoplastic polyurethane (TPU) nanofiber (NF) membranes based TENG. To improve the TENG, the TPU NFs were decorated with multi-walled carbon nanotubes (MWCNT) functionalized with fluoride, amide, and carboxylic groups. The NF demonstrated a stronger interaction with the carboxylic-functionalized MWCNT (c-MWCNT). Furthermore, the c-MWCNT functionalized TPU/PVDF TENGs were evaluated by applying compressive force (30 psi) utilizing a pneumatic cylinder. The maximum alternating voltage, and current outputs were 158 V and 170 <i>µ</i>A respectively. The TENG charging capacity for the samples dipped for 12 h in the c-MWCNT showed an ability to charge a 1 µF capacitor up to 3.03 V in 25 s of hand tapping, suggesting that the fabricated TENG has the capability to function as a self-charging flexible energy harvester.</p><h3 data-test=\"abstract-sub-heading\">Graphical abstract</h3>\u0000","PeriodicalId":16306,"journal":{"name":"Journal of Materials Research","volume":"159 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141512265","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A novel Cu/Ti3C2TX laminated composite foil was prepared using a combination of electroplating and electrophoretic deposition. The results indicate that the average thermal expansion coefficient of the Cu/ Ti3C2TX composite foil decreased by 11.26% compared to that of pure copper. Due to the high electron mobility of Ti3C2TX and the favorable Cu/ Ti3C2TX interface, the electrical conductivity of the Cu/ Ti3C2TX composite foil exceeded that of pure copper by 8.7%, reaching 6.2147 × 107 S·m−1, and its thermal conductivity increased from 381.5 W/m·K to 423.5 W/m·K. The study revealed that a thinner, looser Ti3C2TX layer with fewer layers is more favorable for copper penetration and filling, enabling a continuous network-like structure and resulting in significantly improved thermal and electrical properties of the composite copper foil. These findings position the Cu/Ti3C2TX foil as a promising candidate for electronic encapsulation and super-conductivity.
{"title":"Electrochemical deposition of super-conductive Cu/MXene laminated composite foils with low thermal expansion coefficient","authors":"Chenyu Gao, Jikun Deng, Jiaxing He, Zechuan Wang, Yuanyuan Sheng, Junwu Liu, Honghai Zhong, Guoqing Tong, Yang Jiang","doi":"10.1557/s43578-024-01367-9","DOIUrl":"https://doi.org/10.1557/s43578-024-01367-9","url":null,"abstract":"<p>A novel Cu/Ti<sub>3</sub>C<sub>2</sub>T<sub>X</sub> laminated composite foil was prepared using a combination of electroplating and electrophoretic deposition. The results indicate that the average thermal expansion coefficient of the Cu/ Ti<sub>3</sub>C<sub>2</sub>T<sub>X</sub> composite foil decreased by 11.26% compared to that of pure copper. Due to the high electron mobility of Ti<sub>3</sub>C<sub>2</sub>T<sub>X</sub> and the favorable Cu/ Ti<sub>3</sub>C<sub>2</sub>T<sub>X</sub> interface, the electrical conductivity of the Cu/ Ti<sub>3</sub>C<sub>2</sub>T<sub>X</sub> composite foil exceeded that of pure copper by 8.7%, reaching 6.2147 × 10<sup>7</sup> S·m<sup>−1</sup>, and its thermal conductivity increased from 381.5 W/m·K to 423.5 W/m·K. The study revealed that a thinner, looser Ti<sub>3</sub>C<sub>2</sub>T<sub>X</sub> layer with fewer layers is more favorable for copper penetration and filling, enabling a continuous network-like structure and resulting in significantly improved thermal and electrical properties of the composite copper foil. These findings position the Cu/Ti<sub>3</sub>C<sub>2</sub>T<sub>X</sub> foil as a promising candidate for electronic encapsulation and super-conductivity.</p><h3 data-test=\"abstract-sub-heading\">Graphical Abstract</h3>\u0000","PeriodicalId":16306,"journal":{"name":"Journal of Materials Research","volume":"28 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141512264","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-06-17DOI: 10.1557/s43578-024-01366-w
Ece Bayrak, Mehrdad Forough, Zeynep Tutumlu, Osman Eroğul
A single-step strategy was proposed for the in situ synthesis of silver nanoparticles (AgNps) to prepare polycaprolactone scaffolds with antibacterial activity for decubitus ulcers. AgNps were synthesized, by chemical reduction method, on the surface of electrospun polycaprolactone scaffolds that had been treated with argon plasma. Different AgNO3:NaBH4 molar ratios (1:1–1:6) and PVP concentrations (1–3–5–10%) were investigated. For further studies, AgNO3:NaBH4 molar ratio of 1:3 and a 3% PVP were selected, resulting AgNps with a diameter of 91.54 ± 7.62 nm. Silver release behavior of the scaffolds exhibited a burst release within the first 12 h, followed by a plateau within 2 weeks. The synthesized AgNps demonstrated a potent antibacterial effect against Escherichia coli and Staphylococcus aureus strains, reducing viability down to 15%. PCL scaffolds with AgNps showed increased inhibition zones, 13.33 ± 2.17 mm to 14.94 ± 2.37 mm for E. coli and 14.76 ± 0.24 mm to 16.24 ± 1.45 mm for S. aureus. As a result, this single-step approach can be used as an alternative antibacterial dressing for wound injuries.
{"title":"In situ synthesis of silver nanoparticles as a facile strategy to prepare PCL scaffolds with antibacterial activity for a potential treatment for decubitus ulcers","authors":"Ece Bayrak, Mehrdad Forough, Zeynep Tutumlu, Osman Eroğul","doi":"10.1557/s43578-024-01366-w","DOIUrl":"https://doi.org/10.1557/s43578-024-01366-w","url":null,"abstract":"<p>A single-step strategy was proposed for the in situ synthesis of silver nanoparticles (AgNps) to prepare polycaprolactone scaffolds with antibacterial activity for decubitus ulcers. AgNps were synthesized, by chemical reduction method, on the surface of electrospun polycaprolactone scaffolds that had been treated with argon plasma. Different AgNO<sub>3</sub>:NaBH<sub>4</sub> molar ratios (1:1–1:6) and PVP concentrations (1–3–5–10%) were investigated. For further studies, AgNO<sub>3</sub>:NaBH<sub>4</sub> molar ratio of 1:3 and a 3% PVP were selected, resulting AgNps with a diameter of 91.54 ± 7.62 nm. Silver release behavior of the scaffolds exhibited a burst release within the first 12 h, followed by a plateau within 2 weeks. The synthesized AgNps demonstrated a potent antibacterial effect against <i>Escherichia coli</i> and <i>Staphylococcus aureus</i> strains, reducing viability down to 15%. PCL scaffolds with AgNps showed increased inhibition zones, 13.33 ± 2.17 mm to 14.94 ± 2.37 mm for <i>E. coli</i> and 14.76 ± 0.24 mm to 16.24 ± 1.45 mm for <i>S. aureus</i>. As a result, this single-step approach can be used as an alternative antibacterial dressing for wound injuries.</p><h3 data-test=\"abstract-sub-heading\">Graphical abstract</h3>\u0000","PeriodicalId":16306,"journal":{"name":"Journal of Materials Research","volume":"7 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141530351","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A visible light-induced rGO-Bi2S3/CuO S-scheme heterojunction photocatalyst is explored for the production of methanol and formic acid through photocatalytic CO2 reduction. In this work, the effect of CuO loading on rGO-Bi2S3 nano-hollow flower composite are investigated to improve the yield and selectivity of methanol production. The synthesised rGO-Bi2S3/CuO nanocomposite, being a highly efficient and robust photocatalyst, exhibits the maximum methanol yield of 423.52 μmol gcat.−1 h−1 along with formic acid. CuO loading on rGO-Bi2S3 is responsible for achieving the maximum photocatalytic activity of the rGO-Bi2S3/CuO photocatalyst, the narrowest band gap, the lowest recombination rate of electron–hole pairs, and the increased specific surface area for CO2 capture among all the related photocatalysts, rGO-Bi2S3, pristine Bi2S3, and Bi2S3/CuO nanocomposite. The selectivity of methanol is improved to 98.6% by the rGO-Bi2S3/CuO heterojunction photocatalyst. The absorption edge (652.4 nm) of the rGO-Bi2S3/CuO photocatalyst clearly exhibits outstanding visible light absorption and enhanced photo carrier transportation power.
{"title":"Enhanced yield of methanol using rGO-Bi2S3/CuO heterojunction photocatalyst for CO2 reduction","authors":"Arindam Mandal, Guruprasad Bhattacharya, Kajari Kargupta","doi":"10.1557/s43578-024-01352-2","DOIUrl":"https://doi.org/10.1557/s43578-024-01352-2","url":null,"abstract":"<p>A visible light-induced rGO-Bi<sub>2</sub>S<sub>3</sub>/CuO S-scheme heterojunction photocatalyst is explored for the production of methanol and formic acid through photocatalytic CO<sub>2</sub> reduction. In this work, the effect of CuO loading on rGO-Bi<sub>2</sub>S<sub>3</sub> nano-hollow flower composite are investigated to improve the yield and selectivity of methanol production. The synthesised rGO-Bi<sub>2</sub>S<sub>3</sub>/CuO nanocomposite, being a highly efficient and robust photocatalyst, exhibits the maximum methanol yield of 423.52 μmol g<sub>cat.</sub><sup>−1</sup> h<sup>−1</sup> along with formic acid. CuO loading on rGO-Bi<sub>2</sub>S<sub>3</sub> is responsible for achieving the maximum photocatalytic activity of the rGO-Bi<sub>2</sub>S<sub>3</sub>/CuO photocatalyst, the narrowest band gap, the lowest recombination rate of electron–hole pairs, and the increased specific surface area for CO<sub>2</sub> capture among all the related photocatalysts, rGO-Bi<sub>2</sub>S<sub>3</sub>, pristine Bi<sub>2</sub>S<sub>3</sub>, and Bi<sub>2</sub>S<sub>3</sub>/CuO nanocomposite. The selectivity of methanol is improved to 98.6% by the rGO-Bi<sub>2</sub>S<sub>3</sub>/CuO heterojunction photocatalyst. The absorption edge (652.4 nm) of the rGO-Bi<sub>2</sub>S<sub>3</sub>/CuO photocatalyst clearly exhibits outstanding visible light absorption and enhanced photo carrier transportation power.</p><h3 data-test=\"abstract-sub-heading\">Graphical Abstract</h3>\u0000","PeriodicalId":16306,"journal":{"name":"Journal of Materials Research","volume":"23 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140933739","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-10DOI: 10.1557/s43578-024-01354-0
Manpreet Kaur Ubhi, Manpreet Kaur, Jaspreet Kaur Grewal, Aderbal C. Oliveira, Vijayendra Kumar Garg, Virender K. Sharma
{"title":"Correction: Insight into photocatalytic behavior of magnesium ferrite–bentonite nanocomposite for the degradation of organic contaminants","authors":"Manpreet Kaur Ubhi, Manpreet Kaur, Jaspreet Kaur Grewal, Aderbal C. Oliveira, Vijayendra Kumar Garg, Virender K. Sharma","doi":"10.1557/s43578-024-01354-0","DOIUrl":"https://doi.org/10.1557/s43578-024-01354-0","url":null,"abstract":"","PeriodicalId":16306,"journal":{"name":"Journal of Materials Research","volume":"157 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140933645","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-06DOI: 10.1557/s43578-024-01338-0
V. Panagopoulos, E. Devlin, Y. Sanakis, V. Psycharis, M. Pissas
We examined the crystal and magnetic properties of the polymorphic LiFeO(_2) compound using Mössbauer spectra (MS), X-ray diffraction data (XRD), and magnetic measurements. X-ray diffraction analysis of (alpha)-LiFeO(_2) and (beta ')-LiFeO(_2) phases reveals that short-range ordering observed in the (alpha)-LiFeO(_2) phase is potentially linked to the (beta ')-LiFeO(_2) phase nanoregions. Low-temperature MS of the (alpha)-LiFeO(_2) phase reveal a complicated disordered magnetic state below 90 K. Rietveld analysis of the XRD data of the (gamma)-LiFeO(_2) phase reveals a defect microstructure. These defects produce a complicated distribution of the hyperfine magnetic field estimated from MS. While it is not possible to produce the (beta ')-LiFeO(_2) phase in pure form, extended annealing of the (alpha)-LiFeO(_2) phase at 400 (^circ)C yields a nanocomposite material comprising nanoregions of both (beta ')-LiFeO(_2) and (gamma)-LiFeO(_2) phases.
Graphical abstract
我们使用莫斯鲍尔光谱（MS）、X 射线衍射数据（XRD）和磁性测量方法研究了多晶态 LiFeO(_2) 化合物的晶体和磁性。对（α）-LiFeO（_2）和（β）-LiFeO（_2）相的 X 射线衍射分析表明，在（α）-LiFeO（_2）相中观察到的短程有序化可能与（β）-LiFeO（_2）相纳米区域有关。对（α）-LiFeO（_2）相的 XRD 数据进行的里特维尔德分析揭示了一种有缺陷的微观结构。这些缺陷产生了由 MS 估算的超频磁场的复杂分布。虽然不可能生产出纯的（beta）-LiFeO（_2）相、α）-LiFeO（_2）相在400℃下的扩展退火产生了一种纳米复合材料，这种材料由（β）-LiFeO（_2）相和（gamma）-LiFeO（_2）相的纳米区域组成。图形摘要
{"title":"Short-range nanoregions and nanosized defects in LiFeO $$_2$$ compound deduced from Mössbauer spectroscopy and Rietveld analysis","authors":"V. Panagopoulos, E. Devlin, Y. Sanakis, V. Psycharis, M. Pissas","doi":"10.1557/s43578-024-01338-0","DOIUrl":"https://doi.org/10.1557/s43578-024-01338-0","url":null,"abstract":"<p>We examined the crystal and magnetic properties of the polymorphic LiFeO<span>(_2)</span> compound using Mössbauer spectra (MS), X-ray diffraction data (XRD), and magnetic measurements. X-ray diffraction analysis of <span>(alpha)</span>-LiFeO<span>(_2)</span> and <span>(beta ')</span>-LiFeO<span>(_2)</span> phases reveals that short-range ordering observed in the <span>(alpha)</span>-LiFeO<span>(_2)</span> phase is potentially linked to the <span>(beta ')</span>-LiFeO<span>(_2)</span> phase nanoregions. Low-temperature MS of the <span>(alpha)</span>-LiFeO<span>(_2)</span> phase reveal a complicated disordered magnetic state below 90 K. Rietveld analysis of the XRD data of the <span>(gamma)</span>-LiFeO<span>(_2)</span> phase reveals a defect microstructure. These defects produce a complicated distribution of the hyperfine magnetic field estimated from MS. While it is not possible to produce the <span>(beta ')</span>-LiFeO<span>(_2)</span> phase in pure form, extended annealing of the <span>(alpha)</span>-LiFeO<span>(_2)</span> phase at 400 <span>(^circ)</span>C yields a nanocomposite material comprising nanoregions of both <span>(beta ')</span>-LiFeO<span>(_2)</span> and <span>(gamma)</span>-LiFeO<span>(_2)</span> phases.</p><h3 data-test=\"abstract-sub-heading\">Graphical abstract</h3>\u0000","PeriodicalId":16306,"journal":{"name":"Journal of Materials Research","volume":"2015 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140933545","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-06DOI: 10.1557/s43578-024-01348-y
Hariprasad Gopalan, Jing Rao, Piyush Patil, Chanwon Jung, Se-Ho Kim, Silas Goodrich, Marcel Wetegrove, Angela Kruth, Christina Scheu, Gerhard Dehm, Maria Jazmin Duarte
Amorphous alumina coatings, intended as hydrogen barriers, were successfully deposited on Fe-8 wt% Cr substrates by plasma ion-assisted deposition technique. The amorphous structure of the coatings was confirmed by transmission electron microscopy and X-ray diffraction. The interfacial and mechanical properties of the coating-substrate system were evaluated using an in-house custom-designed backside electrochemical hydrogen charging method. In this approach, the substrate side faces the electrolyte (hydrogen entry side) and the mechanical behavior was tested on the coating side (hydrogen exit side). A Kelvin-probe-based measurement was performed to determine the hydrogen diffusivity in these amorphous alumina coatings at room temperature using a similar backside charging approach. Chemical and microstructural characterizations, in combination with scratch and hardness testing, show that interfacial hydrogen accumulation is strongly responsible for drastic changes in the scratch morphology of the coating and its adhesion to the substrate. Scratch testing promises to be a quick and easy technique to fingerprint changes at the coating/substrate interface upon hydrogen exposure.
Graphical abstract
通过等离子体离子辅助沉积技术，成功地在含铁 8 wt% 的铬基底上沉积了用作氢屏障的非晶氧化铝涂层。透射电子显微镜和 X 射线衍射证实了涂层的非晶结构。利用内部定制的背面电化学氢充电方法，对涂层-基底系统的界面和机械性能进行了评估。在这种方法中，基底面朝向电解质（氢进入面），而机械性能则在涂层面（氢排出面）进行测试。采用类似的背面充氢方法，进行了基于开尔文探针的测量，以确定室温下这些非晶氧化铝涂层中的氢扩散率。结合划痕和硬度测试进行的化学和微观结构表征表明，界面氢积累是涂层划痕形态及其与基体附着力发生剧烈变化的主要原因。划痕测试有望成为一种快速、简便的技术，用于确定氢暴露时涂层/基底界面的变化。
{"title":"Influence of electrochemical hydrogen charging on the mechanical, diffusional, and interfacial properties of an amorphous alumina coating on Fe-8 wt% Cr alloy","authors":"Hariprasad Gopalan, Jing Rao, Piyush Patil, Chanwon Jung, Se-Ho Kim, Silas Goodrich, Marcel Wetegrove, Angela Kruth, Christina Scheu, Gerhard Dehm, Maria Jazmin Duarte","doi":"10.1557/s43578-024-01348-y","DOIUrl":"https://doi.org/10.1557/s43578-024-01348-y","url":null,"abstract":"<p>Amorphous alumina coatings, intended as hydrogen barriers, were successfully deposited on Fe-8 wt% Cr substrates by plasma ion-assisted deposition technique. The amorphous structure of the coatings was confirmed by transmission electron microscopy and X-ray diffraction. The interfacial and mechanical properties of the coating-substrate system were evaluated using an in-house custom-designed backside electrochemical hydrogen charging method. In this approach, the substrate side faces the electrolyte (hydrogen entry side) and the mechanical behavior was tested on the coating side (hydrogen exit side). A Kelvin-probe-based measurement was performed to determine the hydrogen diffusivity in these amorphous alumina coatings at room temperature using a similar backside charging approach. Chemical and microstructural characterizations, in combination with scratch and hardness testing, show that interfacial hydrogen accumulation is strongly responsible for drastic changes in the scratch morphology of the coating and its adhesion to the substrate. Scratch testing promises to be a quick and easy technique to fingerprint changes at the coating/substrate interface upon hydrogen exposure.</p><h3 data-test=\"abstract-sub-heading\">Graphical abstract</h3>\u0000","PeriodicalId":16306,"journal":{"name":"Journal of Materials Research","volume":"49 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140933742","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-02DOI: 10.1557/s43578-024-01351-3
Naved Siraj, S. A. R. Hashmi, Sarika Verma
This study focuses on the modification of halloysite nanotubes (diameter 30–70 nm and length 1–3 µ) using concentrated sulphuric acid to create modified HNTs (mHNTs) and investigates their impact on the properties of PEEK material. Co-rotating twin screw extrusion is employed to incorporate various loadings of mHNTs into the PEEK matrix. The experimental results demonstrate a significant increase in hardness, impact strength, elongation at break, tensile and flexural strengths, and tensile modulus with increasing mHNT concentration. The mHNTs function as bridging tools and reinforcing agents within the polar-nonpolar hybrid system, facilitating compatibility between the blend partners. The composites exhibit improved dynamic thermal and mechanical properties compared to the pure PEEK. The composite materials are further characterized using techniques such as TGA, FESEM, DSC, DMA and FTIR. The enhanced effects observed in the developed composites are attributed to improved interfacial adhesion and favorable interactions between the PEEK matrix and the mHNTs.
{"title":"Influence of modified halloysite nanotube on the properties of poly(ether ether ketone)","authors":"Naved Siraj, S. A. R. Hashmi, Sarika Verma","doi":"10.1557/s43578-024-01351-3","DOIUrl":"https://doi.org/10.1557/s43578-024-01351-3","url":null,"abstract":"<p>This study focuses on the modification of halloysite nanotubes (diameter 30–70 nm and length 1–3 µ) using concentrated sulphuric acid to create modified HNTs (mHNTs) and investigates their impact on the properties of PEEK material. Co-rotating twin screw extrusion is employed to incorporate various loadings of mHNTs into the PEEK matrix. The experimental results demonstrate a significant increase in hardness, impact strength, elongation at break, tensile and flexural strengths, and tensile modulus with increasing mHNT concentration. The mHNTs function as bridging tools and reinforcing agents within the polar-nonpolar hybrid system, facilitating compatibility between the blend partners. The composites exhibit improved dynamic thermal and mechanical properties compared to the pure PEEK. The composite materials are further characterized using techniques such as TGA, FESEM, DSC, DMA and FTIR. The enhanced effects observed in the developed composites are attributed to improved interfacial adhesion and favorable interactions between the PEEK matrix and the mHNTs.</p><h3 data-test=\"abstract-sub-heading\">Graphical abstract</h3>\u0000","PeriodicalId":16306,"journal":{"name":"Journal of Materials Research","volume":"254 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140933745","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-04-30DOI: 10.1557/s43578-024-01346-0
Khemraj Deshmukh, Arindam Bit
The degradation of scaffolds is a critical aspect in tissue engineering and regenerative medicine. Various factors that influence the degradation of scaffold are viscosity, density, hydrophilicity, temperature, cells and degradation environment. In present study, the degradation of scaffold were evaluated in presence of perfused media, Red blood cells (RBC), and cryogenic conditions. Different properties such as density, viscosity and contact angle of bio-ink used for fabrication of scaffold were also evaluated and their correlation to desired environment conditions were also evaluated. A poly electrolyte complex scaffolds (chitosan: alginate, chitosan: gelatine), and explicit scaffolds were considered for degradation study. Explicit scaffold and PEC scaffolds were fabricated form chitosan, alginate and gelatine at mixing ratio of 20:80, 50:50, and 80:20 concentration by solvent casting and etching method. The scaffold degradation studies in perfused media were performed at flow rate of 0.5 ml/min, 1 ml/min and 2 ml/min. The parameters related to degradation of scaffold such as weight and pH of discharge media were also evaluated. Results indicated that degradation of chitosan: alginate at 20:80 concentration had shown maximum degradation in presence of RBCs. Similarly, degradation pattern was equal to linear patten for all the scaffolds except 20:80 and 50:50 concentration of chitosan-alginate in cryogenic conditions. Result of scaffolds degradation in perfused media had shown that scaffolds were degraded maximal at a flow rate of 1 ml/min as compare to other flow rates. Contact angle measurement had proved that all PEC scaffold belongs to the category of hydrophilic family. The scaffold fabricated from higher concentration of chitosan had revealed slower degradation as compare to others configuration. The acceleration of scaffold degradation was tiggered by enzymatic and cellular activities in the presence of RBCs. Perfused media had caused scaffold degradation due to presence of mechanical shear stress.
{"title":"Evaluating the effect of cryopreservation, cell migration and perfused media on degradation of porous scaffold","authors":"Khemraj Deshmukh, Arindam Bit","doi":"10.1557/s43578-024-01346-0","DOIUrl":"https://doi.org/10.1557/s43578-024-01346-0","url":null,"abstract":"<p>The degradation of scaffolds is a critical aspect in tissue engineering and regenerative medicine. Various factors that influence the degradation of scaffold are viscosity, density, hydrophilicity, temperature, cells and degradation environment. In present study, the degradation of scaffold were evaluated in presence of perfused media, Red blood cells (RBC), and cryogenic conditions. Different properties such as density, viscosity and contact angle of bio-ink used for fabrication of scaffold were also evaluated and their correlation to desired environment conditions were also evaluated. A poly electrolyte complex scaffolds (chitosan: alginate, chitosan: gelatine), and explicit scaffolds were considered for degradation study. Explicit scaffold and PEC scaffolds were fabricated form chitosan, alginate and gelatine at mixing ratio of 20:80, 50:50, and 80:20 concentration by solvent casting and etching method. The scaffold degradation studies in perfused media were performed at flow rate of 0.5 ml/min, 1 ml/min and 2 ml/min. The parameters related to degradation of scaffold such as weight and pH of discharge media were also evaluated. Results indicated that degradation of chitosan: alginate at 20:80 concentration had shown maximum degradation in presence of RBCs. Similarly, degradation pattern was equal to linear patten for all the scaffolds except 20:80 and 50:50 concentration of chitosan-alginate in cryogenic conditions. Result of scaffolds degradation in perfused media had shown that scaffolds were degraded maximal at a flow rate of 1 ml/min as compare to other flow rates. Contact angle measurement had proved that all PEC scaffold belongs to the category of hydrophilic family. The scaffold fabricated from higher concentration of chitosan had revealed slower degradation as compare to others configuration. The acceleration of scaffold degradation was tiggered by enzymatic and cellular activities in the presence of RBCs. Perfused media had caused scaffold degradation due to presence of mechanical shear stress.</p><h3 data-test=\"abstract-sub-heading\">Graphical abstract</h3>\u0000","PeriodicalId":16306,"journal":{"name":"Journal of Materials Research","volume":"13 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140838702","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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