Pub Date : 2024-11-19DOI: 10.1016/j.jallcom.2024.177666
Sarthak Paikray, Sujata Kumari Ray, Priyanka Nayak, A.K. Sahoo, Surya Narayan Prusty, S. Dash, Sushri Sangita Nanda
Self-activated tungstates doped with lanthanide ions are an excellent class of phosphor materials, exhibiting promising luminescence efficiency as well as stability which opens up their vast arena of applications. In this work, a detailed comparative study has been carried out on Sm3+ doped Ba/CaWO4 phosphors, synthesized via solid state reaction route. The structural, morphological and photo-physical properties have been investigated through various analytical techniques. The optical band gap and the refractive index of the phosphors have been estimated through diffuse reflectance spectroscopy. A 5-fold enhancement of the emission intensity is observed in CaWO4 as compared to BaWO4 phosphors owing to high asymmetrical environment. The underlying mechanisms of photoluminescence and energy transfer process (WO42+→Sm3+) are discussed in detail. The colour tuning from orange red to pure red emission is obtained from the Commission International de l'Eclairage (CIE) diagram. Better luminescent properties with desirable quantum yield, absorption efficiency and suitable Correlated Colour Temperature (CCT) and colour purity (91%) values allow the optimised phosphors for diverse potential applications such as solid-state lighting, security ink for anti-counterfeiting, latent fingerprint detection, etc.
{"title":"Comparative Analysis of Sm3+-doped BaWO4 and CaWO4 Phosphors: Properties and Application in Latent Fingerprints and Anti-Counterfeiting","authors":"Sarthak Paikray, Sujata Kumari Ray, Priyanka Nayak, A.K. Sahoo, Surya Narayan Prusty, S. Dash, Sushri Sangita Nanda","doi":"10.1016/j.jallcom.2024.177666","DOIUrl":"https://doi.org/10.1016/j.jallcom.2024.177666","url":null,"abstract":"Self-activated tungstates doped with lanthanide ions are an excellent class of phosphor materials, exhibiting promising luminescence efficiency as well as stability which opens up their vast arena of applications. In this work, a detailed comparative study has been carried out on Sm<sup>3+</sup> doped Ba/CaWO<sub>4</sub> phosphors, synthesized via solid state reaction route. The structural, morphological and photo-physical properties have been investigated through various analytical techniques. The optical band gap and the refractive index of the phosphors have been estimated through diffuse reflectance spectroscopy. A 5-fold enhancement of the emission intensity is observed in CaWO<sub>4</sub> as compared to BaWO<sub>4</sub> phosphors owing to high asymmetrical environment. The underlying mechanisms of photoluminescence and energy transfer process (WO<sub>4</sub><sup>2+</sup>→Sm<sup>3+</sup>) are discussed in detail. The colour tuning from orange red to pure red emission is obtained from the Commission International de l'Eclairage (CIE) diagram. Better luminescent properties with desirable quantum yield, absorption efficiency and suitable Correlated Colour Temperature (CCT) and colour purity (91%) values allow the optimised phosphors for diverse potential applications such as solid-state lighting, security ink for anti-counterfeiting, latent fingerprint detection, etc.","PeriodicalId":344,"journal":{"name":"Journal of Alloys and Compounds","volume":"18 1","pages":""},"PeriodicalIF":6.2,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142673394","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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 : 2024-11-19DOI: 10.1016/j.jallcom.2024.177655
Fanglei Ding, Shihao Chen, Wenfeng Zhang, Lingjun Wei, Min Jiang, Yunfeng Zhu, Yana Liu, Jiguang Zhang, Jun Wang, Zhixin Ba
The YMg2Ni9 hydrogen storage alloy in-situ coated with Ni3S2 was successfully prepared by hydrothermal sulfurization treatment and investigated as the anode material in nickel-metal hydride (Ni-MH) batteries for the first time. Owing to the high electronic conductivity and electrocatalytic activity of Ni3S2 nanoflake coating, the electrochemical performance of the YMg2Ni9 alloy electrode is significantly enhanced. The alloy electrode treated in 0.3 M Na2S solution exhibits the highest discharge capacity of 230.8 mAh/g and superior cycling stability, maintaining a capacity retention rate of 85.1% after 100 cycles. The increase in the discharge capacity of the electrode is credited to the Ni3S2 coating on the surface of the alloy, which possesses a nanoflake structure, facilitating the surface electrochemical reaction and providing more channels for hydrogen diffusion. In addition, Ni3S2 nanoflakes wrapped around the surface of the alloy can stabilize the reaction interface between the alloy and the electrolyte and slow down the alkali erosion, thus improving the cycle life of the electrode. The present study offers beneficial information for investigating a potential anode material for Ni-MH batteries.
{"title":"Electrochemical performance of YMg2Ni9 hydrogen storage electrode alloy in-situ coated with Ni3S2","authors":"Fanglei Ding, Shihao Chen, Wenfeng Zhang, Lingjun Wei, Min Jiang, Yunfeng Zhu, Yana Liu, Jiguang Zhang, Jun Wang, Zhixin Ba","doi":"10.1016/j.jallcom.2024.177655","DOIUrl":"https://doi.org/10.1016/j.jallcom.2024.177655","url":null,"abstract":"The YMg<sub>2</sub>Ni<sub>9</sub> hydrogen storage alloy in-situ coated with Ni<sub>3</sub>S<sub>2</sub> was successfully prepared by hydrothermal sulfurization treatment and investigated as the anode material in nickel-metal hydride (Ni-MH) batteries for the first time. Owing to the high electronic conductivity and electrocatalytic activity of Ni<sub>3</sub>S<sub>2</sub> nanoflake coating, the electrochemical performance of the YMg<sub>2</sub>Ni<sub>9</sub> alloy electrode is significantly enhanced. The alloy electrode treated in 0.3<!-- --> <!-- -->M Na<sub>2</sub>S solution exhibits the highest discharge capacity of 230.8<!-- --> <!-- -->mAh/g and superior cycling stability, maintaining a capacity retention rate of 85.1% after 100 cycles. The increase in the discharge capacity of the electrode is credited to the Ni<sub>3</sub>S<sub>2</sub> coating on the surface of the alloy, which possesses a nanoflake structure, facilitating the surface electrochemical reaction and providing more channels for hydrogen diffusion. In addition, Ni<sub>3</sub>S<sub>2</sub> nanoflakes wrapped around the surface of the alloy can stabilize the reaction interface between the alloy and the electrolyte and slow down the alkali erosion, thus improving the cycle life of the electrode. The present study offers beneficial information for investigating a potential anode material for Ni-MH batteries.","PeriodicalId":344,"journal":{"name":"Journal of Alloys and Compounds","volume":"14 1","pages":""},"PeriodicalIF":6.2,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142670997","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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 : 2024-11-19DOI: 10.1016/j.jallcom.2024.177671
Maysa K.S. Araújo, Adriana S. Carvalho, Alexsandro R. Santos, Eduardo Padrón-Hernández, Eduardo H.L. Falcão
This study evaluates the impact of graphene oxide (GO) and reduced graphene oxide (rGO) on the structural characteristics and electromagnetic interference shielding effectiveness (EMI SE) of poly(vinyl alcohol) (PVA) films containing titanium dioxide (TiO₂). The composite films were prepared by solution casting, and their structural properties were analyzed through FTIR, electron microscopy, and X-ray diffraction. EMI SE was evaluated as a function of GO and rGO concentrations. Spectroscopic data indicated that TiO₂ and GO interact with PVA primarily through hydrogen bonding. The inclusion of TiO₂ increased the crystallinity of the films, although its interaction with PVA was not uniform. In composites containing GO, TiO₂ exhibited enhanced affinity for the polymer matrix due to the hydrophilic nature of both components. As a result, GO influenced the action of TiO₂ in the composite, leading to EMI SE values of 3.27 dB/mm in the X-band and 7.28 dB/mm at 9.3 GHz. The addition of rGO led to reduced interaction with TiO₂ due to a lower content of oxygen-containing groups, with the higher electrical conductivity of rGO being the most prominent effect observed. rGO demonstrated a competitive effect at 1% filler and a synergistic effect at 4% filler, with EMI SE values at 9.9 GHz increasing to 31.34 dB/mm and 55.80 dB/mm, respectively. This study shows that GO/TiO₂/PVA and rGO/TiO₂/PVA composite films exhibit promising EMI shielding properties. The different interactions between GO and rGO with TiO₂ and PVA result in distinct EMI SE mechanisms, with rGO showing superior performance. Combined with excellent mechanical flexibility and relatively low thickness, these data highlight the potential of these composite films for EMI shielding applications.
本研究评估了氧化石墨烯（GO）和还原氧化石墨烯（rGO）对含有二氧化钛（TiO₂）的聚乙烯醇（PVA）薄膜的结构特性和电磁干扰屏蔽效果（EMI SE）的影响。通过溶液浇铸制备了复合薄膜，并通过傅立叶变换红外光谱、电子显微镜和 X 射线衍射分析了其结构特性。EMI SE 作为 GO 和 rGO 浓度的函数进行了评估。光谱数据表明，TiO₂ 和 GO 主要通过氢键与 PVA 相互作用。加入 TiO₂ 增加了薄膜的结晶度，尽管它与 PVA 的相互作用并不均匀。在含有 GO 的复合材料中，由于两种成分都具有亲水性，TiO₂ 与聚合物基质的亲和力增强。因此，GO 影响了复合材料中 TiO₂ 的作用，导致 X 波段的 EMI SE 值为 3.27 dB/mm，9.3 GHz 时为 7.28 dB/mm。添加 rGO 后，由于含氧基团的含量降低，与 TiO₂ 的相互作用减弱，而 rGO 较高的导电性是观察到的最显著效果。rGO 在 1%填料时表现出竞争效应，在 4% 填料时表现出协同效应，在 9.9 GHz 时的 EMI SE 值分别增加到 31.34 dB/mm 和 55.80 dB/mm。这项研究表明，GO/TiO₂/PVA 和 rGO/TiO₂/PVA 复合薄膜具有良好的 EMI 屏蔽性能。GO 和 rGO 与 TiO₂ 和 PVA 之间不同的相互作用产生了不同的 EMI SE 机制，其中 rGO 表现出更优越的性能。结合出色的机械柔韧性和相对较低的厚度，这些数据凸显了这些复合薄膜在 EMI 屏蔽应用方面的潜力。
{"title":"Influence of graphene oxide and reduced graphene oxide on TiO2-reinforced flexible poly(vinyl alcohol) films for electromagnetic interference shielding","authors":"Maysa K.S. Araújo, Adriana S. Carvalho, Alexsandro R. Santos, Eduardo Padrón-Hernández, Eduardo H.L. Falcão","doi":"10.1016/j.jallcom.2024.177671","DOIUrl":"https://doi.org/10.1016/j.jallcom.2024.177671","url":null,"abstract":"This study evaluates the impact of graphene oxide (GO) and reduced graphene oxide (rGO) on the structural characteristics and electromagnetic interference shielding effectiveness (EMI SE) of poly(vinyl alcohol) (PVA) films containing titanium dioxide (TiO₂). The composite films were prepared by solution casting, and their structural properties were analyzed through FTIR, electron microscopy, and X-ray diffraction. EMI SE was evaluated as a function of GO and rGO concentrations. Spectroscopic data indicated that TiO₂ and GO interact with PVA primarily through hydrogen bonding. The inclusion of TiO₂ increased the crystallinity of the films, although its interaction with PVA was not uniform. In composites containing GO, TiO₂ exhibited enhanced affinity for the polymer matrix due to the hydrophilic nature of both components. As a result, GO influenced the action of TiO₂ in the composite, leading to EMI SE values of 3.27<!-- --> <!-- -->dB/mm in the X-band and 7.28<!-- --> <!-- -->dB/mm at 9.3<!-- --> <!-- -->GHz. The addition of rGO led to reduced interaction with TiO₂ due to a lower content of oxygen-containing groups, with the higher electrical conductivity of rGO being the most prominent effect observed. rGO demonstrated a competitive effect at 1% filler and a synergistic effect at 4% filler, with EMI SE values at 9.9<!-- --> <!-- -->GHz increasing to 31.34<!-- --> <!-- -->dB/mm and 55.80<!-- --> <!-- -->dB/mm, respectively. This study shows that GO/TiO₂/PVA and rGO/TiO₂/PVA composite films exhibit promising EMI shielding properties. The different interactions between GO and rGO with TiO₂ and PVA result in distinct EMI SE mechanisms, with rGO showing superior performance. Combined with excellent mechanical flexibility and relatively low thickness, these data highlight the potential of these composite films for EMI shielding applications.","PeriodicalId":344,"journal":{"name":"Journal of Alloys and Compounds","volume":"6 1","pages":""},"PeriodicalIF":6.2,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142671004","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
With the combination of carbon quantum dots (CDs) and rare earth-doped fluorescent materials, multi-mode luminescence can be achieved in fluorescent ink, thereby enhancing its anti-counterfeiting security coefficient. However, the self-quenching process in CDs currently hinders their application in the field of anti-counterfeiting. In this study, we employed simple chemical method to prepare the SiO2-encapsulated YVO4:Eu3+/CDs nanocomposites, which greatly improved the stability of the composite and achieved dual-mode solid-state luminescence. Quick response code anti-counterfeiting patterns were fabricated using screen printing technology, and dual-mode luminescence performance with red and blue emission was achieved under excitation at 254 nm and 365 nm respectively. The YVO4:Eu3+@SiO2@CDs nanocomposites showed stable dual-mode luminescent performance in both solid-state and solvent environment, demonstrating great potential in anticounterfeiting and information protection application.
碳量子点（CD）与掺稀土的荧光材料相结合，可以在荧光油墨中实现多模式发光，从而提高其防伪安全系数。然而，目前 CD 的自淬过程阻碍了其在防伪领域的应用。本研究采用简单的化学方法制备了二氧化硅封装的 YVO4:Eu3+/CDs 纳米复合材料，大大提高了复合材料的稳定性，并实现了双模固态发光。利用丝网印刷技术制作了快速响应代码防伪图案，并在 254 纳米和 365 纳米激发下分别实现了红色和蓝色发射的双模发光性能。YVO4:Eu3+@SiO2@CDs纳米复合材料在固态和溶剂环境下均表现出稳定的双模发光性能，在防伪和信息保护方面具有巨大的应用潜力。
{"title":"Dual-mode Luminescence and Anti-counterfeiting Application of YVO4: Eu3+@SiO2@CDs Nanocomposites","authors":"Jiantao Lü, Ting Fan, Jie Liang, Yayun Zhou, Tingting Deng, Ruming Jiang","doi":"10.1016/j.jallcom.2024.177664","DOIUrl":"https://doi.org/10.1016/j.jallcom.2024.177664","url":null,"abstract":"With the combination of carbon quantum dots (CDs) and rare earth-doped fluorescent materials, multi-mode luminescence can be achieved in fluorescent ink, thereby enhancing its anti-counterfeiting security coefficient. However, the self-quenching process in CDs currently hinders their application in the field of anti-counterfeiting. In this study, we employed simple chemical method to prepare the SiO<sub>2</sub>-encapsulated YVO<sub>4</sub>:Eu<sup>3+</sup>/CDs nanocomposites, which greatly improved the stability of the composite and achieved dual-mode solid-state luminescence. Quick response code anti-counterfeiting patterns were fabricated using screen printing technology, and dual-mode luminescence performance with red and blue emission was achieved under excitation at 254<!-- --> <!-- -->nm and 365<!-- --> <!-- -->nm respectively. The YVO<sub>4</sub>:Eu<sup>3+</sup>@SiO<sub>2</sub>@CDs nanocomposites showed stable dual-mode luminescent performance in both solid-state and solvent environment, demonstrating great potential in anticounterfeiting and information protection application.","PeriodicalId":344,"journal":{"name":"Journal of Alloys and Compounds","volume":"69 1","pages":""},"PeriodicalIF":6.2,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142670962","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ferrimagnets have attracted increasing attention in spintronics due to the possibility of easy manipulation by magnetic or electric fields. We report the anomalous Hall effect (AHE) and spin Hall magnetoresistance (SMR) in ferrimagnetic Mn1.77Co0.44V0.83Al0.96 (MCVA) films, which are sensitive to the disorder of the film. As the thickness of the film increases, the film gradually transitions from the disordered to the ordered state, resulting in the anomalous Hall resistivity (ρAH) changes from negative to positive. By separating their distinct the contributions to the AHE, we demonstrate that the thickness dependence originates from the competition between the skew scattering contribution and the sum of the side jump and intrinsic contributions. Moreover, under the effect of disorder, the dependence of the SMR ratio on thickness is more complex, and a critical level of disorder may lead to a sharp decrease in the SMR ratio. Our research reveals the impact of disorder on spin transport and provides a pathway for the design of ferrimagnetic Heusler alloy-based spintronic devices.
{"title":"Effect of disorder on anomalous Hall effect and spin Hall magnetoresistance in the ferrimagnetic film","authors":"Chunyue Dou, Xiaoyi Zhao, Xiaoguang Xu, Ang Li, Zhiqiang Zhu, Tanzhao Zhang, Chexin Li, Kangkang Meng, Yong Wu, Yong Jiang","doi":"10.1016/j.jallcom.2024.177674","DOIUrl":"https://doi.org/10.1016/j.jallcom.2024.177674","url":null,"abstract":"Ferrimagnets have attracted increasing attention in spintronics due to the possibility of easy manipulation by magnetic or electric fields. We report the anomalous Hall effect (AHE) and spin Hall magnetoresistance (SMR) in ferrimagnetic Mn<sub>1.77</sub>Co<sub>0.44</sub>V<sub>0.83</sub>Al<sub>0.96</sub> (MCVA) films, which are sensitive to the disorder of the film. As the thickness of the film increases, the film gradually transitions from the disordered to the ordered state, resulting in the anomalous Hall resistivity (<em>ρ</em><sub>AH</sub>) changes from negative to positive. By separating their distinct the contributions to the AHE, we demonstrate that the thickness dependence originates from the competition between the skew scattering contribution and the sum of the side jump and intrinsic contributions. Moreover, under the effect of disorder, the dependence of the SMR ratio on thickness is more complex, and a critical level of disorder may lead to a sharp decrease in the SMR ratio. Our research reveals the impact of disorder on spin transport and provides a pathway for the design of ferrimagnetic Heusler alloy-based spintronic devices.","PeriodicalId":344,"journal":{"name":"Journal of Alloys and Compounds","volume":"7 1","pages":""},"PeriodicalIF":6.2,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142673388","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We successfully prepare BiFe(1-x)PdxO3 (BFPxO) thin films (i.e. ferroelectric bismuth ferrite with Fe-site partially substituted by palladium ions) as well as BFPxO/NiO heterostructure though sol-gel method. We try to figure out the two aspects of problems in this work. On one hand, crucial roles that Pd doping plays in optoelectronic characteristics of BFPxO are elucidated. The relationships among Pd valence, lattice distortion and optoelectronic performance of BFPxO are built. We confirm that Pd doping can minimize the response time constant of BiFe(1-x)PdxO3 below 10 ms; meanwhile, the detectivity of BFPO/NiO heterostructure can reach up to ca. 109 Jones. On the other hand, open-circuit voltage decay (OCVD), a kind of transient measurement technique, is adopted to gain an insight into distinct decay stages existing in BFPxO. The abnormal transient phenomenon with ‘overlong’ relaxation time higher than 10 s is probably contributed by depolarization process of BFPxO. Consequently, we reveal hidden photoactive natures of ferroic perovskite oxides, which may derive from the synergic kinetics of polarization/depolarization associating to ferroelectric domains and particularly be triggered by the noble metal element doping.
{"title":"Decoupling the synergic kinetics of depolarization in ferroelectric Pd-doped bismuth ferrite photoactive thin films","authors":"Zhuoyue Wang, Shuai Ma, Pengkun Zhang, Fengjin Xia, Quanyu He, Wenshu Yang, Lifeng Dong","doi":"10.1016/j.jallcom.2024.177652","DOIUrl":"https://doi.org/10.1016/j.jallcom.2024.177652","url":null,"abstract":"We successfully prepare BiFe<sub>(1-<em>x</em>)</sub>Pd<sub><em>x</em></sub>O<sub>3</sub> (BFP<sub><em>x</em></sub>O) thin films (i.e. ferroelectric bismuth ferrite with Fe-site partially substituted by palladium ions) as well as BFP<sub><em>x</em></sub>O/NiO heterostructure though sol-gel method. We try to figure out the two aspects of problems in this work. On one hand, crucial roles that Pd doping plays in optoelectronic characteristics of BFP<sub><em>x</em></sub>O are elucidated. The relationships among Pd valence, lattice distortion and optoelectronic performance of BFP<sub><em>x</em></sub>O are built. We confirm that Pd doping can minimize the response time constant of BiFe<sub>(1-<em>x</em>)</sub>Pd<sub><em>x</em></sub>O<sub>3</sub> below 10 ms; meanwhile, the detectivity of BFPO/NiO heterostructure can reach up to ca. 10<sup>9</sup> Jones. On the other hand, open-circuit voltage decay (OCVD), a kind of transient measurement technique, is adopted to gain an insight into distinct decay stages existing in BFP<sub><em>x</em></sub>O. The abnormal transient phenomenon with ‘overlong’ relaxation time higher than 10<!-- --> <!-- -->s is probably contributed by depolarization process of BFP<sub><em>x</em></sub>O. Consequently, we reveal hidden photoactive natures of ferroic perovskite oxides, which may derive from the synergic kinetics of polarization/depolarization associating to ferroelectric domains and particularly be triggered by the noble metal element doping.","PeriodicalId":344,"journal":{"name":"Journal of Alloys and Compounds","volume":"173 1","pages":""},"PeriodicalIF":6.2,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142670961","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In order to improve the utilisation of sunlight and expand the photoresponsive range of the photocatalyst, a visible light responsive 2D/0D binary heterojunction: Eu-Bi12O17Cl2/Bi14W2O27, was prepared in this paper by a controlled solvent-thermal method. The enhancement of photocatalytic activity originates from the following synergistic effects, including the unique 2D/0D contact interface, the enhancement of the photoresponsive range, and the introduction of the elemental Eu which makes the light-absorbing edge towards the visible light direction. The results of characterisation and photocatalysis experiments show that the 2D/0D catalyst has good spectral absorption range and redox capacity. In the experiments conducted with a xenon lamp as a simulated sunlight, the CO yield reached 44 μmol·g-1·h-1. The mechanism of electron transfer was analysed in conjunction with Density functional theory (DFT) calculations, laying the foundation for the subsequent development of photocatalysts in this field.
{"title":"Eu-Bi12O17Cl2/Bi14W2O27 2D/0D heterojunction for efficient photocatalytic reduction of CO2 to CO","authors":"Yi-Nan Zheng, Wen-Ze Liu, Shu-Yan Wang, Li-Guo Gao","doi":"10.1016/j.jallcom.2024.177649","DOIUrl":"https://doi.org/10.1016/j.jallcom.2024.177649","url":null,"abstract":"In order to improve the utilisation of sunlight and expand the photoresponsive range of the photocatalyst, a visible light responsive 2D/0D binary heterojunction: Eu-Bi<sub>12</sub>O<sub>17</sub>Cl<sub>2</sub>/Bi<sub>14</sub>W<sub>2</sub>O<sub>27</sub>, was prepared in this paper by a controlled solvent-thermal method. The enhancement of photocatalytic activity originates from the following synergistic effects, including the unique 2D/0D contact interface, the enhancement of the photoresponsive range, and the introduction of the elemental Eu which makes the light-absorbing edge towards the visible light direction. The results of characterisation and photocatalysis experiments show that the 2D/0D catalyst has good spectral absorption range and redox capacity. In the experiments conducted with a xenon lamp as a simulated sunlight, the CO yield reached 44 μmol·g<sup>-1</sup>·h<sup>-1</sup>. The mechanism of electron transfer was analysed in conjunction with Density functional theory (DFT) calculations, laying the foundation for the subsequent development of photocatalysts in this field.","PeriodicalId":344,"journal":{"name":"Journal of Alloys and Compounds","volume":"89 1","pages":""},"PeriodicalIF":6.2,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142670998","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The rational design of cost-effective and stable heterogeneous nanocatalysts with high activities is vital yet challenged for utilization of sustainable hydrogen fuel. Herein, we report a novel surficial alkaline functional strategy for immobilization of non-noble CuCo nanoparticles (NPs) on diamine-alkalized-functionalized Ti3C2 surfaces (CuCo/PDA-Ti3C2). By virtue of coordination effect, ultrafine CuCo NPs with the size of 1.8 nm were well dispersed on Ti3C2 surface. Strikingly, the optimized CuCo/PDA-Ti3C2 nanocatalyst presents an impressive catalytic performance toward ammonia borane hydrolysis (ABH) without any additive, with a completed conversion and a high turnover frequency (TOF) value of 71.8 molH2molcat-1min-1 at mild condition. The alkaline amine groups induced a strong support-metal synergistic interaction (SMSI) to not only regulate the localized charge distribution and electron energy levels near active sites, but also optimize the surface d center and adsorption/desorption behavior, resulting in an accelerating O-H bond cleavage in water molecular. This work presents a novel and universal strategy for developing alkaline titanium carbide (MXene)-based heterogeneous nanocatalysts for hydrogen energy society.
{"title":"Alkaline titanium carbide (MXene) engineering ultrafine non-noble nanocatalysts toward remarkably boosting hydrogen evolution from ammonia borane hydrolysis","authors":"Haotian Qin, Siyuang Tang, Linlin Xu, Aosong Li, Quanjiang Lv, Jianling Dong, Luyu Liu, Xiang Ding, Xueqing Pan, Xinchun Yang, Nan Jiang, Fuzhan Song","doi":"10.1016/j.jallcom.2024.177644","DOIUrl":"https://doi.org/10.1016/j.jallcom.2024.177644","url":null,"abstract":"The rational design of cost-effective and stable heterogeneous nanocatalysts with high activities is vital yet challenged for utilization of sustainable hydrogen fuel. Herein, we report a novel surficial alkaline functional strategy for immobilization of non-noble CuCo nanoparticles (NPs) on diamine-alkalized-functionalized Ti<sub>3</sub>C<sub>2</sub> surfaces (CuCo/PDA-Ti<sub>3</sub>C<sub>2</sub>). By virtue of coordination effect, ultrafine CuCo NPs with the size of 1.8<!-- --> <!-- -->nm were well dispersed on Ti<sub>3</sub>C<sub>2</sub> surface. Strikingly, the optimized CuCo/PDA-Ti<sub>3</sub>C<sub>2</sub> nanocatalyst presents an impressive catalytic performance toward ammonia borane hydrolysis (ABH) without any additive, with a completed conversion and a high turnover frequency (TOF) value of 71.8 mol<sub>H2</sub>mol<sub>cat</sub><sup>-1</sup>min<sup>-1</sup> at mild condition. The alkaline amine groups induced a strong support-metal synergistic interaction (SMSI) to not only regulate the localized charge distribution and electron energy levels near active sites, but also optimize the surface d center and adsorption/desorption behavior, resulting in an accelerating O-H bond cleavage in water molecular. This work presents a novel and universal strategy for developing alkaline titanium carbide (MXene)-based heterogeneous nanocatalysts for hydrogen energy society.","PeriodicalId":344,"journal":{"name":"Journal of Alloys and Compounds","volume":"106 1","pages":""},"PeriodicalIF":6.2,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142671002","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Layered H-UiO-66@IL composites with both intraparticle micropores, interparticle mesopores, and multiple active sites were prepared. A key aspect of the technique was the addition of deionized water during solvothermal synthesis, which rapidly nucleated layered nanoparticles. A multifunctional, flexible, and stable polyacrylonitrile (PAN)-based membrane was successfully constructed by incorporating H-UiO-66 nanoparticles, modified by ionic liquid (1-allyl-3-butylimidazole tetrafluoroborate), into polymers with macromolecular chains under mild, controlled conditions. The resulting film exhibited excellent dielectric, ferroelectric, and mechanical properties due to the multilayer fiber design. Furthermore, the PAN matrix showed a higher content (97.41%) of planar zigzag conformations, enhancing the piezoelectric properties. The composite film demonstrated ultra-high sensitivity (10.98 V/N) and an ultra-low detection limit of 3.5 × 10⁻⁴ N. In addition, the film passed 1,800-cycle stability tests and maintained its initial output value across various environmental conditions. This flexible piezoelectric sensor shows significant potential for aiding deaf and mute individuals in sign language or breathing communication.
{"title":"A flexible wearable sensor based on improving the piezoelectric layer performance of sandwich structures with micro-/mesopores for communication with the deaf-mute","authors":"Qianbing Lin, Qisong Shi, Jun Fu, Wenjuan Zhang, Qiang Liu, Yibo Wu","doi":"10.1016/j.jallcom.2024.177646","DOIUrl":"https://doi.org/10.1016/j.jallcom.2024.177646","url":null,"abstract":"Layered H-UiO-66@IL composites with both intraparticle micropores, interparticle mesopores, and multiple active sites were prepared. A key aspect of the technique was the addition of deionized water during solvothermal synthesis, which rapidly nucleated layered nanoparticles. A multifunctional, flexible, and stable polyacrylonitrile (PAN)-based membrane was successfully constructed by incorporating H-UiO-66 nanoparticles, modified by ionic liquid (1-allyl-3-butylimidazole tetrafluoroborate), into polymers with macromolecular chains under mild, controlled conditions. The resulting film exhibited excellent dielectric, ferroelectric, and mechanical properties due to the multilayer fiber design. Furthermore, the PAN matrix showed a higher content (97.41%) of planar zigzag conformations, enhancing the piezoelectric properties. The composite film demonstrated ultra-high sensitivity (10.98<!-- --> <!-- -->V/N) and an ultra-low detection limit of 3.5 × 10⁻⁴ N. In addition, the film passed 1,800-cycle stability tests and maintained its initial output value across various environmental conditions. This flexible piezoelectric sensor shows significant potential for aiding deaf and mute individuals in sign language or breathing communication.","PeriodicalId":344,"journal":{"name":"Journal of Alloys and Compounds","volume":"22 1","pages":""},"PeriodicalIF":6.2,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142670957","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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 : 2024-11-19DOI: 10.1016/j.jallcom.2024.177626
A. García-Gómez, V. Zhukova, J.M. Blanco, A. Zhukov
In this article we study the effect of conventional and stress annealing on the magnetic properties and giant magnetoimpedance (GMI) effect of Co65.3Si12.0B10.2Cr8.5Fe3.9Mo0.1 microwires with low and positive magnetostriction coefficient and low Curie temperature. A remarkable tuning capacity of both GMI effect and hysteresis loops is observed for a broad range of annealing conditions up to 350∘C and 320 MPa. We report appearance of double-peaks magnetic field dependencies of the GMI-ratio related with the coexistence of two different contributions originated by two different magnetic domain structure for the stress-annealed microwires. The observed experimental results are discussed in terms of the internal stresses relaxation derived from the annealing procedures, the induced magnetic anisotropy and local atomic reordering. The studies of Co-rich microwires with low and positive magnetostriction coefficient and low Curie temperature are potentially suitable for development of smart composites with embedded microwires for wireless temperature monitoring.
{"title":"Effect of annealing properties on Giant Magnetoimpedance of Co-rich glass-coated microwires","authors":"A. García-Gómez, V. Zhukova, J.M. Blanco, A. Zhukov","doi":"10.1016/j.jallcom.2024.177626","DOIUrl":"https://doi.org/10.1016/j.jallcom.2024.177626","url":null,"abstract":"In this article we study the effect of conventional and stress annealing on the magnetic properties and giant magnetoimpedance (GMI) effect of Co<sub>65.3</sub>Si<sub>12.0</sub>B<sub>10.2</sub>Cr<sub>8.5</sub>Fe<sub>3.9</sub>Mo<sub>0.1</sub> microwires with low and positive magnetostriction coefficient and low Curie temperature. A remarkable tuning capacity of both GMI effect and hysteresis loops is observed for a broad range of annealing conditions up to 350<sup>∘</sup>C and 320 MPa. We report appearance of double-peaks magnetic field dependencies of the GMI-ratio related with the coexistence of two different contributions originated by two different magnetic domain structure for the stress-annealed microwires. The observed experimental results are discussed in terms of the internal stresses relaxation derived from the annealing procedures, the induced magnetic anisotropy and local atomic reordering. The studies of Co-rich microwires with low and positive magnetostriction coefficient and low Curie temperature are potentially suitable for development of smart composites with embedded microwires for wireless temperature monitoring.","PeriodicalId":344,"journal":{"name":"Journal of Alloys and Compounds","volume":"3 1","pages":""},"PeriodicalIF":6.2,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142673386","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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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