TRIBOLOGY INTERNATIONAL
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2024
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IF 6.1
Xingtao Cheng,Yi He,Siming Yan,Liping Yan,Zhiyuan Li,Shijun Xu,Kaijun Wei,Yi Fan,Quangang Chen,Wanwan Peng
Wear and erosion are common issues encountered when applying metal components in harsh marine environments. In this study, N-MX@ZnO materials were prepared by a synergistic modification of Ti 3 C 2 T x using ethylenediamine and zinc oxide quantum dots. Subsequently, the Ni-Cu/N-MX@ZnO coating was deposited onto J55 steel using pulsed electrodeposition, exhibiting excellent tribological properties. The toughness, wear, and seawater erosion behavior of the coatings were investigated. The results demonstrated that the COF value of the Ni-Cu/N-MX@ZnO coating was reduced by 48.23% and the impedance value was increased by 300% in comparison to the pure sample. The enhancement mechanism can be attributed to the physical barrier effect and uniform dispersion effect of N-MX@ZnO, which caused the Ni-Cu/N-MX@ZnO coatings to form a friction-transferring film during the friction process.
研究领域:
材料科学
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表面工程
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海洋工程
✓ 已验证
产品关联
DOI
高影响因子
Nanoscale
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2020
·Vol. 12
·期 31
·16605-16616
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IF 6.895
Rong Dai,Ziliang Zheng,Chenshuai Lian,Kai Shi,Xu Wu,Xia An,Xianmei Xie
To enhance the catalytic performance of catalysts for the ethanol steam reforming (ESR) reaction, a facile reverse micelle strategy was adopted to prepare a core@shell Ni–Cu@Ca–SiO2 (Ni–Cu@CS) nanoreactor composed of an ultra-small Ni–Cu alloy (∼2.8 nm) encapsulated in Ca-functionalized SiO2 nanoparticles. Benefiting from its core@shell structural features and unique components, the Ni–Cu@CS nanoreactor exhibited superior activity (69.91% H2 selectivity and 99.99% ethanol conversion) and stability compared to reference samples. The regenerated Ni–Cu@CS nanoreactor showed high stability, maintaining 98.14% ethanol conversion and only 1.98 mg gcat−1 h−1 in carbon deposition. The high catalytic performance of Ni–Cu@CS is attributed to not only its encapsulated structure, which effectively prevented the sintering of neighboring Ni–Cu alloy nanoparticles, but also to its Ca-functionalized porous SiO2 shell, suppressing the carbon deposition. Moreover, its porous thin shell facilitated the mass transfer and diffusion of reactants and products. Thus, the Ni–Cu@CS nanoreactor is expected to become a new type of high-efficiency nanoreactor for the ESR reaction.
研究领域:
催化化学
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材料科学
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能源化学
✓ 已验证
DOI
高影响因子
Nano Research
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2024
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IF 9.5
Li Jing,Jing Chuanyong,Wang Jin
Electrocatalytic CO 2 reduction to CH 4 remains challenging due to multi-electron transfer and intermediates adsorption. Herein, we synthesized electrocatalysts by growing Ni-Cu alloy structure on nitrogen-doped carbon nanotubes (Ni x Cu y -NCNT) for electrocatalytic CO 2 reduction reaction (CO 2 RR) via hydrothermal method followed by pyrolysis. The optimized Ni 1 Cu 1 -NCNT demonstrated a superior CO 2 RR performance, achieving 99.7% \(\text{FE}_{\text{CH}_{4}}\) (FE = Faradaic efficiency) and 11.54 mA • cm −2 current density at −1.2 V vs. reversible hydrogen electrode (RHE), which outperformed single metal counterparts. Its outstanding performance was due to the electrons transferred from Cu to Ni and Ni-Cu alloy shifted the d-band center toward the Fermi level, which was more conducive to the intermediate formation. In situ electrochemical attenuated total reflection (EC-ATR) and density functional theory (DFT) calculations revealed the appearance of *CHO intermediate and the pathway during the CO 2 RR process. The design of the bimetallic electrocatalyst in this study provides a new perspective for the highly selective reduction of CO 2 .
研究领域:
材料科学
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电化学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
Green Chemical Engineering
·
2025
·
IF 7.6
Jiankun Yu,Weixiao Sun,Kuan Huang,Jin Xu,Fuzeyu Zhong,Xiaohu Ge,Wenyao Chen,Gang Qian,Yueqiang Cao,Jianrong Zeng,Jianbo Ma,Xinggui Zhou,Xuezhi Duan,Jing Zhang,Lilong Jiang
Due to escalating carbon emissions, increasing attention is being focused on the synthesis of biomass-derived liquid fuels with a low CO 2 footprint. Currently, the dominant biobased liquid fuel in the diesel range is green diesel, produced via deoxygenation of non-edible natural/waste oils and their free fatty acid components into engine-compatible diesel-range alkanes. Industrially, sulfided NiMo or CoMo catalysts are typically used, leading to total hydrocarbon yields of 70-80 wt%. However, their inevitable sulfur leaching often contaminates the products and requires the addition of sulfur-containing agents. Here, we developed a highly selective sulfur-free Ni-Cu alloy catalyst by disentangling the electronic and size effects, to enable green diesel synthesis through the decarbonylation of palmitic acid—the most common fatty acid in these feedstocks. An unprecedented decarbonylation product (pentadecane) yield of 98% (on a molar basis) was achieved using a Ni-Cu alloy catalyst with a Ni/Cu ratio of 1:1 under mild reaction conditions (2 MPa H 2 , 250 °C). Minimal metal sintering or leaching was observed after multiple reuses. Kinetic studies show that incorporating Cu into Ni markedly reduces both the apparent activation energy and the reaction order for the conversion of palmitic acid. These results, combined with catalyst characterization, reveal that introducing Cu into Ni not only facilitates the adsorption and activation of the carboxylic hydroxyl group to promote the reductive deoxygenation of palmitic acid into aldehyde/alcohol intermediates—the slow step in decarbonylation—but also weakens the adsorption of C–C bonds on Ni by enhancing its electron density.
研究领域:
能源化学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
Molecular Catalysis
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2022
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IF 5.089
Kuan Wang,Zhe Cao,Junlei Wang,Zhen-Hong He,Dan Wang,Rong-Rong Zhang,Weitao Wang,Yang Yang,Zhao-Tie Liu
The development of non-precious metal catalysts in heterogeneous catalytic processes is of great importance to the hydrogenation of quinolines for both theoretical and industrial applications. Herein, an effective non-precious metal catalyst, 58% Fe 4 Ni 6 Cu 5 /MCM-41, was developed to catalyze the hydrogenation of quinolines under the green and mild conditions, which can achieve 97.5% conversion and exceeding 98% selectivity to tetrahydroquinoline in solvent-free at low temperature of 50 °C. Moreover, the acceptable results of the reusability and gram scale-up experiments proved an industrial application potential of the as-prepared catalyst. Meanwhile, in cyclohexane system, 58% Fe 4 Ni 6 Cu 5 /MCM-41 catalyst can further realize a higher activity of the hydrogenation at a lower temperature of 40 °C, achieving 98.2% conversion and 98% selectivity to tetrahydroquinoline. The existence of Fe-Ni and Ni-Cu alloys in Fe 4 Ni 6 Cu 5 /MCM-41 catalyst was demonstrated by TEM, XRD, XPS, H 2 -TPD, and Raman spectroscopy. And, Fe-Ni and Ni-Cu alloys can be well dispersed onto MCM-41 molecular sieves. For Fe 4 Ni 6 Cu 5 /MCM-41 catalyst, quinoline molecules can be adsorbed by Fe 3+ species on the surface of Fe-Ni alloy through the coordination, while hydrogen molecules can be adsorbed and activated by Ni-Cu alloy. Under the synergism of Fe-Ni and Ni-Cu alloys, the highly effective and selective hydrogenation of quinolines was achieved at low temperature and in solvent-free system. The present approach offers a prospective idea for building non-precious metal catalysts to realize the effective hydrogenation of N-heterocyclic compounds under mild conditions.
研究领域:
催化化学
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材料科学
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绿色化学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
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IF 5.1
Changhong Zhou,Rui Ling,Menglei Wang,Chao Yang,Wentao Qi
Syngas , a mixture of H 2 and CO with adjustable compositional ratios, can be directly produced via H 2 O/CO 2 co-electrolysis in solid oxide electrolysis cells (SOECs). In this study, We have developed a strategy to enhance the catalytic activity of titanate perovskite cathodes by constructing active metal-oxide interfaces through the in-situ growth of Ni x Cu 1-x alloy nanocatalysts (x = 0, 0.25, 0.5, 0.75 and 1) on LST matrix. The evenly distribution of Ni x Cu 1-x alloy nanoparticles (∼30 nm) on the LST substrate has been confirmed through a serious of characterization techniques, including XRD , XPS, SEM and TEM. Specifically, the LSTNi 0.75 Cu 0.25 cathode demonstrated an optimal synergistic effect , achieving high efficiency in the co-electrolysis of H 2 O/CO 2 to syngas. Under an applied voltage of 1.6 V at 800 °C, the syngas production rate reaches 5.43H 2 and 3.48 CO ml min −1 cm −2 with ∼96 % Faradaic efficiency. Furthermore, the composition of the produced syngas can be finely tuned in a broad range from 0.8 to 3.5 b y simply adjusting the inlet gas composition (H 2 O/CO 2 ratio) and the operating temperature. The LSTNi 0.75 Cu 0.25 cathode, when subjected to continuous H 2 O/CO 2 co-electrolysis for 100 h, exhibited remarkable stability, attributing to the robust and active nature of the metal-oxide interfaces.
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）