IF 3.8 2区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Vacuum

Pub Date : 2024-11-13 DOI: 10.1016/j.vacuum.2024.113830

Junqiang Ren , Xinyue Zhang , Qing Gao , Qi Wang , Junchen Li , Hongtao Xue , Xuefeng Lu , Fuling Tang

Interstitial oxygen significantly affects the mechanical properties of α-Titanium (α-Ti) by modifying dislocation slip and deformation twinning mechanisms. This study utilizes molecular dynamics simulations to investigate the influence of interstitial oxygen atoms on the tensile mechanical properties and deformation mechanisms of nano polycrystalline α-Ti, taking into account two distinct average grain sizes and varying gradients of oxygen content. The pinning effect of interstitial oxygen atoms on grain boundary relaxation dislocations is critical for stabilizing the nano-polycrystalline grain boundaries (GBs), with this effect becoming increasingly pronounced as the oxygen content rises. Additionally, the simulation results indicate that oxygen atoms at the twin boundary enhance the stability of the {10

\overline{1}

2} twin boundary while exerting minimal influence on the migration of the {10

\overline{1}

1} twin boundary. The deformation associated with {10

\overline{1}

1} twinning leads to a crystallographic orientation transformation of the entire grain, which contrasts with the conventional grain rotation mechanism typically observed in nanocrystals. During plastic deformation, the primary dislocation slip mechanism is identified as the Shockley partial dislocation

\frac{1}{3}

<

\overline{1}

100>, whereas the basal plane perfect dislocation

\frac{1}{3}

<11

\overline{2}

0> easily dissociates into two Shockley partial dislocations due to the pinning effect of oxygen atoms. As a result, the dislocation density of the Shockley partial dislocation

\frac{1}{3}

<

\overline{1}

100> is the highest.

间隙氧通过改变位错滑移和变形孪生机制，对α-钛（α-Ti）的机械性能产生了重大影响。本研究利用分子动力学模拟研究了间隙氧原子对纳米多晶α-钛的拉伸机械性能和变形机制的影响，同时考虑了两种不同的平均晶粒尺寸和不同的氧含量梯度。间隙氧原子对晶界弛豫位错的钉扎效应对于稳定纳米多晶晶界（GBs）至关重要，随着氧含量的增加，这种效应越来越明显。此外，模拟结果表明，孪晶边界上的氧原子增强了{10 1‾ 2}孪晶边界的稳定性，同时对{101‾ 1}孪晶边界的迁移影响极小。与{101‾1}孪晶相关的形变会导致整个晶粒的晶体学取向转变，这与纳米晶体中通常观察到的传统晶粒旋转机制截然不同。在塑性变形过程中，主要的位错滑移机制被确定为肖克利部分位错 13 <1‾100>，而基底面完美位错 13 <112‾0>由于氧原子的钉扎效应，很容易解离成两个肖克利部分位错。因此，肖克利部分位错 13 <1‾ 100> 的位错密度最高。

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引用次数: 0

Design a self-reinforcement buffer layer to assist braze SiC and Nb with Cu-xTiH2 filler alloy 设计一种自强化缓冲层，以辅助碳化硅和铌与铜-xTiH2 填充合金的钎焊

IF 3.8 2区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Vacuum

Pub Date : 2024-11-12 DOI: 10.1016/j.vacuum.2024.113829

Qiang Ma , Zhekai Zhu , Peng He , Yongwei Chen , Shujin Chen , Jun Wang

A buffer layer was designed to assist to braze SiC and Nb. The effect of brazing temperature and holding time on the microstructure and the shear strength of the joint was analyzed. The strengthening mechanism of the joint was evaluated. The results found that the SiC-Nb joint was brazed with Cu-5TiH₂, because of its good wettability on the surface of SiC. The typical microstructure of SiC-Nb joint brazed at 1060 °C for 5 min was SiC/C particles + TiC + Cu(s,s)/α-Ti + Nb(s,s)/Cu(s,s)+(Ti,Nb)₅Si₃+Ti₅Si₃/α-Ti/(Ti,Nb)Si/Nb. In addition, a buffer layer formed, which was consisted of two parts: reaction layer (α-Ti + Nb(s,s)) and infiltration layer (much C particles, little TiC and Cu(s,s)). With brazing temperature and holding time increasing, element Nb continuously diffused into brazing seam and solidified into α-Ti. With Nb content increasing, the α-Ti existed in the form of discontinuous to continuous layer, and then to particles. When Nb solidified into α-Ti continuous layer, the strength of the layer was improved and effective joining between SiC and Nb formed. In addition, the buffer layer was contributed to forming a good gradient transition of coefficient of thermal expansion (CTE), and released residual stress. So, the shear strength of the joint was increased to 52.6 MPa.

设计了一个缓冲层来辅助钎焊碳化硅和铌。分析了钎焊温度和保温时间对接头微观结构和剪切强度的影响。对接头的强化机制进行了评估。结果发现，SiC-Nb 接头采用 Cu-5TiH2 进行钎焊，因为 Cu-5TiH2 在 SiC 表面具有良好的润湿性。在 1060 °C 下钎焊 5 分钟的 SiC-Nb 接头的典型微观结构为 SiC/C 颗粒 + TiC + Cu(s,s)/α-Ti + Nb(s,s)/Cu(s,s)+(Ti,Nb)5Si3+Ti5Si3/α-Ti/(Ti,Nb)Si/Nb 。此外，还形成了缓冲层，缓冲层由两部分组成：反应层（α-Ti + Nb(s,s)）和浸润层（大量 C 粒子，少量 TiC 和 Cu(s,s)）。随着钎焊温度和保温时间的增加，Nb 元素不断扩散到钎缝中，并凝固成 α-Ti。随着铌含量的增加，α-钛以不连续层到连续层，再到颗粒的形式存在。当铌凝固成α-钛连续层时，α-钛连续层的强度得到提高，SiC 和铌之间形成了有效的连接。此外，缓冲层还有助于形成良好的热膨胀系数（CTE）梯度转变，并释放残余应力。因此，接头的剪切强度提高到了 52.6 兆帕。

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引用次数: 0

Thermodynamic modelling of a twin-stage claw vacuum pump and its gas pressurization analysis 双级爪式真空泵的热力学模型及其气体增压分析

IF 3.8 2区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Vacuum

Pub Date : 2024-11-12 DOI: 10.1016/j.vacuum.2024.113821

Yuanjie Xin , Chunji Ren , Jun Wang , Shiyang Pan , Tao Nie , Zengli Wang , Dong Cui

Multi-stage claw vacuum pumps are crucial in various industrial applications for efficiently achieving high vacuum levels compared to other positive displacement vacuum pumps. In order to elucidate the gas pressurization process of the multi-stage claw vacuum pump and clarify its structural design principles, the authors investigated a twin-stage claw vacuum pump as the main research subject, and analyzed its working characteristic. A thermodynamic model of the twin-stage claw vacuum pump describing the pressurization process was established, and the results were verified by means of experiments. Moreover, effects of the phase difference φ_Ⅰ-Ⅱ, the first-stage discharge port angle θ_d,Ⅰ and the thickness ratio B₁:B₂ on pump performance were discussed. Results show that as φ_Ⅰ-Ⅱ increases, the pump power of the first stage gradually increases, while the power of the second stage decreases and then increases. With the increase of θ_d,Ⅰ, the pump power decreases and then increases. When the suction pressure is 10 kPa, the specific power reaches its minimum value under B₁: B₂ = 2:1. As the suction pressure increases, the pump power gradually increases, and its specific power fells substantially and then levels out. These contents are of great significance for the design and optimization of multi-stage claw vacuum pumps.

与其他容积式真空泵相比，多级爪式真空泵能有效地实现高真空度，因此在各种工业应用中起着至关重要的作用。为了阐明多级爪式真空泵的气体增压过程，明确其结构设计原理，作者以双级爪式真空泵为主要研究对象，分析了其工作特性。建立了描述增压过程的双级爪式真空泵热力学模型，并通过实验对结果进行了验证。此外，还讨论了相位差φⅠ-Ⅱ、第一级出气口角度θd,Ⅰ和厚度比 B1:B2 对泵性能的影响。结果表明，随着φⅠ-Ⅱ的增大，第一级泵的功率逐渐增大，而第二级泵的功率先减小后增大。随着θd,Ⅰ的增大，泵功率先减小后增大。当吸入压力为 10 kPa 时，比功率在 B1: B2 = 2:1 条件下达到最小值。随着吸入压力的增大，泵的功率逐渐增大，比功率大幅下降，然后趋于平稳。这些内容对多级爪式真空泵的设计和优化具有重要意义。

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引用次数: 0

Preparation of Au@AuAg yolk-shell nanoparticles with porous surface and their catalytic reduction of 4-nitrophenol 具有多孔表面的 Au@AuAg 卵黄壳纳米粒子的制备及其对 4-硝基苯酚的催化还原作用

IF 3.8 2区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Vacuum

Pub Date : 2024-11-12 DOI: 10.1016/j.vacuum.2024.113828

Meng Yao, Sitong Zhao, Xiankui Lv, Junqi Tang

Yolk-shell structure nanoparticles, consisting of outer shell, inner core and cavity, are a combination of core-shell structure and hollow structure. Due to the existence of their internal gaps, yolk-shell nanostructures have more excellent optoelectronic properties than hollow nanostructures and core-shell nanostructures, and have promising applications in catalysis, energy storage, drug delivery, lithium batteries, biosensors and nanoreactors. In this paper, gold-silver bimetallic yolk-shell nanoparticles (Au@AuAg Y-SNPs) with porous surface structure were synthesized. The morphology and structure of Au@AuAg Y-SNPs were characterized by UV–vis, XRD, SEM, TEM, HRTEM, SAED, and HAADF-STEM, the results demonstrated that the nanostructures are composed of gold and silver bimetals with various shell thickness, and tunable internal voids. In addition, the catalytic activity of the Au@AuAg yolk-shell nanoparticles were investigated based on the model catalytic reaction of hydrogenation reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) with superfluous sodium borohydride. The yolk-shell nanostructure had the best catalytic activity when the ratio of Ag to Au was 1:4. The kinetic constant of the reaction, apparent rate constants (K_app) was 0.0072 s⁻¹ when 100 μL of this nanocatalyst was added. This suggests that Au@AuAg Y-SNPs have a promising application in the removal of pollutants from water bodies and environmental remediation.

卵壳结构纳米粒子由外壳、内核和空腔组成，是核壳结构和空心结构的结合体。由于其内部间隙的存在，卵黄壳纳米结构比空心纳米结构和核壳纳米结构具有更优异的光电性能，在催化、储能、药物输送、锂电池、生物传感器和纳米反应器等领域具有广阔的应用前景。本文合成了具有多孔表面结构的金银双金属卵壳纳米颗粒（Au@AuAg Y-SNPs）。通过紫外可见光、X射线衍射、扫描电镜、电子显微镜、HRTEM、SAED和HAADF-STEM对Au@AuAg Y-SNPs的形貌和结构进行了表征，结果表明该纳米结构由金银双金属组成，具有不同的壳厚度和可调的内部空隙。此外，还以过量硼氢化钠将 4-硝基苯酚（4-NP）加氢还原为 4-氨基苯酚（4-AP）的模型催化反应为基础，研究了 Au@AuAg 卵黄壳纳米粒子的催化活性。当银与金的比例为 1:4 时，蛋黄壳纳米结构的催化活性最好。当加入 100 μL 该纳米催化剂时，反应的动力学常数（表观速率常数 (Kapp) ）为 0.0072 s-1。这表明 Au@AuAg Y-SNPs 在去除水体污染物和环境修复方面具有广阔的应用前景。

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引用次数: 0

Defect engineering of anchored on F-doped BNNR surface to enhance low-frequency microwave absorption and achieve exceptional thermal conductivity properties 锚定在掺杂 F 的 BNNR 表面的缺陷工程，可增强低频微波吸收并实现优异的导热性能

IF 3.8 2区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Vacuum

Pub Date : 2024-11-10 DOI: 10.1016/j.vacuum.2024.113826

Zhen Lv , Zhongyang Duan , Ning Jiang , Ruoxuan Zheng , Di Yin , Yufeng Bai , Tingting Yang , Tai Peng

The growing demand for AI and smart computing drives the development of compact, lightweight electronic products to mitigate electromagnetic wave (EMW) pollution and thermal management issues. This necessitates materials with enhanced microwave absorption (MA) and optimal thermal conductivity (TC). Herein, we designed and synthesized fluorinated boron nitride nanorods (F-BNNRs) in a single step via plasma ball milling. Ammonium fluoride (NH₄F) served as the fluorinating agent for hexagonal boron nitride nanorods (h-BNNRs). F-BNNR3, with a NH₄F to h-BNNR ratio of 10:1 and 5.84 % fluorine (F) content, exhibits excellent MA, achieving a minimum reflection loss (RLmin) of −68.56 dB at 5.14 GHz with a thickness of 4.32 mm. It also displays a broad MA frequency range (4.6–6.1 GHz, 15.4–17.2 GHz) with significant RL < −10 dB. Additionally, a 0.09 wt% F-BNNR3 solution achieves a thermal conductivity (TC) of 0.95 W m⁻¹K⁻¹, 134 % higher than that of a 0.09 wt% h-BNNR dispersion fluid. Following a post-static treatment, F-BNNR3 attains a TC of 0.86 W m⁻¹K⁻¹, 118 % higher than that of h-BNNR. The incorporation of F into h-BNNRs significantly enhances MA and TC performance, addressing EMW pollution and thermal management challenges in advanced communication technologies utilizing nanofluids.

对人工智能和智能计算日益增长的需求推动了紧凑型轻质电子产品的发展，以减轻电磁波（EMW）污染和热管理问题。这就要求材料具有更强的微波吸收能力（MA）和最佳的热导率（TC）。在此，我们通过等离子体球磨一步法设计并合成了氟化氮化硼纳米棒（F-BNNRs）。氟化铵（NH₄F）是六方氮化硼纳米棒（h-BNNRs）的氟化剂。F-BNNR3 的 NH₄F 与 h-BNNR 的比例为 10:1，氟（F）含量为 5.84%，具有出色的 MA 性能，在 5.14 GHz 频率下，厚度为 4.32 mm 时的最小反射损耗（RLmin）为 -68.56 dB。它还显示出宽广的 MA 频率范围（4.6-6.1 GHz、15.4-17.2 GHz），RL < -10 dB。此外，0.09 wt% F-BNNR3 溶液的热导率 (TC) 达到 0.95 W m-1K-1，比 0.09 wt% h-BNNR 分散液的热导率高 134%。经过后静态处理后，F-BNNR3 的导热系数为 0.86 W m-1K-1，比 h-BNNR 高 118%。在 h-BNNR 中加入 F 可显著提高 MA 和 TC 性能，从而解决利用纳米流体的先进通信技术中的电磁波污染和热管理难题。

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引用次数: 0

Development and diagnostic study of the RF nitrogen atom source 射频氮原子源的开发和诊断研究

IF 3.8 2区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Vacuum

Pub Date : 2024-11-09 DOI: 10.1016/j.vacuum.2024.113820

Mengting Li, Xin Xu, Wubin Wu, Shixiang Peng, Weiping Chen, Zhiyi Zhai, Qing Luo, Haiping Peng, Ailin Zhang

With the development of thin film technology, particularly the increasing demand for research on group III nitride materials, the need for N ions has significantly increased. A wider and more efficient RF nitrogen atom source specifically designed for nitride film growth has been developed. To evaluate the nitrogen atom density from the RF nitrogen source, a global model of RF nitrogen gas discharge plasma was created. This model was calibrated by measuring the emission spectrum of RF nitrogen gas discharge, and the relationships between nitrogen atom density and actual working pressure, power, and discharge chamber size were determined. It was found that the nitrogen atom density increases with increasing power and initially increases with pressure before decreasing. Finally, the nitrogen atom density was determined, achieving an 18 % nitrogen atom dissociation rate and a nitrogen atom density of 5 × 10¹²/cm³ at an RF power of 400 W. This density is significantly higher than that of nitrogen ions, indicating that this is a nitrogen atom source with high purity.

随着薄膜技术的发展，特别是对 III 族氮化物材料研究的需求不断增加，对氮离子的需求也大大增加。专门为氮化物薄膜生长设计的更广泛、更高效的射频氮原子源已经开发出来。为了评估射频氮源的氮原子密度，创建了一个射频氮气放电等离子体的全局模型。通过测量射频氮气放电的发射光谱对该模型进行了校准，并确定了氮原子密度与实际工作压力、功率和放电室尺寸之间的关系。结果发现，氮原子密度随功率的增加而增加，最初随压力的增加而增加，然后再减小。最后，对氮原子密度进行了测定，在射频功率为 400 W 时，氮原子解离率为 18%，氮原子密度为 5 × 1012/cm³，明显高于氮离子的密度，表明这是一种高纯度的氮原子源。

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引用次数: 0

Influence of the growth rate during Nb film pulsed laser deposition on the sapphire R-plane 铌薄膜脉冲激光沉积过程中的生长速率对蓝宝石 R 平面的影响

IF 3.8 2区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Vacuum

Pub Date : 2024-11-09 DOI: 10.1016/j.vacuum.2024.113827

I.V. Malikov

Optimal conditions for obtaining high quality epitaxial Nb thin films on the monocrystalline sapphire R-plane by pulsed laser deposition in ultrahigh vacuum have been determined. The ratio of room temperature resistance to the residual resistance (RRR) on the substrate temperature has the maximum at about 630 °C. The RRR dependence on the growth rate has the maximum at growth rates of 3–6 nm/min. In epitaxial Nb films, there is a simultaneous increase in the value of RRR and growth misorientation of Nb(001) relatively sapphire R-plane. At the maximum value of RRR, the shapes of Nb X-ray diffraction (XRD) peaks (002) and (011) are symmetrical and close to the Gaussian distribution; at lower RRR values, the shapes of XRD peaks become asymmetrical and cannot be approximated by a single Gaussian distribution, and their shape can be described by the sum of several Gaussian functions. For all obtained films, full width at half maximum (FWHM) of Nb (002) and Nb (011) peaks are 0.2^o and 0.4^о, respectively. FWHM of Nb (002) rocking curves is 0.4^o.

确定了在超高真空中通过脉冲激光沉积在单晶蓝宝石 R 平面上获得高质量铌外延薄膜的最佳条件。室温电阻与残余电阻 (RRR) 与基底温度的比率在约 630 °C 时达到最大值。RRR 与生长速率的关系在生长速率为 3-6 nm/min 时达到最大值。在外延铌薄膜中，RRR 值和相对蓝宝石 R 面的铌(001)生长错向同时增加。在 RRR 最大值时，铌 X 射线衍射（XRD）峰 (002) 和 (011) 的形状是对称的，接近高斯分布；在 RRR 值较低时，XRD 峰的形状变得不对称，不能用单一的高斯分布来近似，其形状可以用多个高斯函数的和来描述。对于所有获得的薄膜，铌（002）和铌（011）峰的半最大全宽（FWHM）分别为 0.2o 和 0.4о。铌（002）摇摆曲线的全宽最大值为 0.4o。

引用次数: 0

Wide-temperature-range tribological properties of Cu-Ni-Al films with multiple oxidation states 具有多种氧化态的铜-镍-铝薄膜的宽温度范围摩擦学特性

IF 3.8 2区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Vacuum

Pub Date : 2024-11-09 DOI: 10.1016/j.vacuum.2024.113823

Ziluo Cheng , Xiao Wang , Xiaona Li , Zhumin Li , Yinglin Hu , Qiao Jiang , Renwei Liu , Yuandi Hou , Min Li , Rui Zheng , Chuang Dong

High-temperature (HT) apparatus suffer from galling and seizure of contact interface, for which a wear-resistant film is helpful but challenging to design. In this work, the Cu-Ni-Al films prepared by magnetron sputtering provide effective wear-resistant protection for Ni-based superalloy over room temperature (RT) to 800 °C, decreasing the coefficient of friction by 45 %, 30 %, 15 % and wear rate by 97 %, 65 %, 62 % at RT, 400 °C, 600 °C, respectively, and exhibiting especially low wear rate 1.88 × 10⁻⁵mm³N⁻¹m⁻¹ at 800 °C. Layered structure with multiple oxidation states formed during friction is the crucial, with the Cu₂O-rich layer and the CuO layer serving lubrication at RT and HT, respectively. The FCC + L1₂ structure ensures the high-temperature carrying capacity and film-substrate adhesion. AFM investigation exhibits the microscale tribological behavior is relevance with Ni + Al content. This work provides a novel strategy for the design and preparation of wide-temperature-range wear-resistant film.

高温（HT）设备的接触界面会出现咬合和咬合现象，为此需要设计一种耐磨薄膜，但这种薄膜的设计具有挑战性。在这项工作中，通过磁控溅射制备的铜-镍-铝薄膜为镍基超合金提供了有效的耐磨保护，在室温（RT）至 800 °C 的条件下，摩擦系数分别降低了 45%、30%、15%，磨损率在室温、400 °C 和 600 °C 条件下分别降低了 97%、65%、62%，尤其是在 800 °C 条件下，磨损率低至 1.88 × 10-5mm3N-1m-1。摩擦过程中形成的多氧化态分层结构是关键所在，其中富含 Cu2O 的层和 CuO 层分别在 RT 和 HT 条件下起到润滑作用。FCC + L12 结构确保了高温承载能力和薄膜与基底的粘附性。原子力显微镜研究表明，微尺度摩擦学行为与 Ni + Al 含量相关。这项研究为设计和制备宽温范围耐磨薄膜提供了一种新策略。

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引用次数: 0

A new system for sample synthesis, preparation and modification combined with in-situ depth profiling using medium energy ions 利用中等能量离子进行样品合成、制备和改性以及原位深度剖析的新系统

IF 3.8 2区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Vacuum

Pub Date : 2024-11-09 DOI: 10.1016/j.vacuum.2024.113824

Radek Holeňák , Dmitrii Moldarev , Eleni Ntemou , Theofanis Tsakiris , Carolin Frank , Kevin Vomschee , Svenja Lohmann , Daniel Primetzhofer

We present equipment for sample synthesis, preparation and modification enabling in-situ studies employing medium energy ion beams at the ion implanter facility of the Tandem Laboratory national research infrastructure at Uppsala University. The integral instrumentation enables controlled thin-film synthesis, modification and characterization applicable to study near-surface processes such as thin-film growth, phase transformation, oxidation, annealing, catalysis or ion implantation. We describe the available instrumentation with its specifications and present four demonstrative experiments with a particular focus on the acquired in-situ capabilities addressing 1) Evaporation and thermal alloying of thin films – nickel silicides 2) Reactive magnetron sputtering and controlled oxidization – photochromic YHO 3) Sputtering and low-energy implantation – hydrogen in tungsten and 4) Surface cleaning of sensitive systems – self-supporting silicon membranes.

我们在乌普萨拉大学 Tandem 实验室国家研究基础设施的离子注入器设备上展示了用于样品合成、制备和改性的设备，这些设备能够利用中等能量离子束进行原位研究。这些完整的仪器可实现可控薄膜合成、改性和表征，适用于研究薄膜生长、相变、氧化、退火、催化或离子注入等近表面过程。我们介绍了现有的仪器及其规格，并展示了四项演示实验，重点是已获得的原位能力，包括 1) 薄膜的蒸发和热合金化--硅化镍 2) 反应磁控溅射和离子注入。2) 反应磁控溅射和受控氧化--光致变色 YHO 3) 溅射和低能植入--钨中的氢和 4) 敏感系统的表面清洁--自支撑硅膜。

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引用次数: 0

Fe-based monolithic catalysts for Fenton-like degradation of organic dyes: The important role of Fe2(OH)3Cl species 用于有机染料 Fenton 类降解的铁基整体催化剂：Fe2(OH)3Cl 物种的重要作用

IF 3.8 2区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Vacuum

Pub Date : 2024-11-09 DOI: 10.1016/j.vacuum.2024.113822

Shixian Huang , Hongbo Yao , Helen J. Sun , Hanxi Xiao , Xiao Liu , Chuanbo Hu , Jianting Tang , Joe R. Zhao

Fe-based heterogeneous catalysts are promising in Fenton-like reactions for wastewater treatment, but their practical application is hindered by their recyclability, and the fundamental mechanisms for origin of the high performance and the structure-activity relationships remain to be elucidated further. In this paper, we prepared a series of Fe₂(OH)₃Cl-containing monolith catalysts by the use of NH₄Cl additives, which gave significantly higher performance than the Fe₃O₄ counterparts in Fenton-like degradation of methylene blue and rhodamine B when H₂O₂ was used as oxidant. The Fe₂(OH)₃Cl-containing monolith catalyst can be reused four cycles in the degradation experiments without big loss in their activity. The active radicals generated during process of the catalytic degradation were studied.

铁基异相催化剂在废水处理的 Fenton 类反应中具有广阔的应用前景，但其可回收性阻碍了其实际应用，而且其高性能的基本起源机制和结构-活性关系仍有待进一步阐明。本文利用 NH4Cl 添加剂制备了一系列含 Fe2(OH)3Cl 的整体石催化剂，当 H2O2 作为氧化剂时，这些催化剂在亚甲基蓝和罗丹明 B 的 Fenton 类降解中的性能明显高于 Fe3O4 催化剂。含 Fe2（OH）3Cl 的整体催化剂可在降解实验中重复使用四次，而其活性不会大幅降低。对催化降解过程中产生的活性自由基进行了研究。

引用次数: 0

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