JOM
·
2021
·Vol. 73
·期 11
·3451-3459
·
IF 2.474
Chen Ben,Li Zhi-Bo,Zhang Guo-Hua,Chou Kuo-Chih
To improve the performance of Mo-based cermets, Mo-(Ni)-Al 2 O 3 cermets were prepared with raw materials of nano-sized Al 2 O 3 powder. The effects of Al 2 O 3 and Ni additions on the densification behavior, microstructure, bending strength, and hardness of the Mo-(Ni)-Al 2 O 3 cermets were experimentally analyzed. The results showed the content of Al 2 O 3 had a great influence on the degree of densification of Mo-Al 2 O 3 cermets at the sintering temperature of 1600°C. In addition, the Al 2 O 3 particles were distributed evenly in the matrix of Mo-based cermets, which refined the grains of Mo and increased the hardness of cermets. Because of the weak interfacial bonding strength between Al 2 O 3 ceramic phase and Mo metal phase, the bending strength decreased continuously with increasing Al 2 O 3 content. However, Ni addition improved the wetting and adhesion of Al 2 O 3 and Mo. With the addition of Ni, the relative density increased, and thus hardness and bending strength were improved.
研究领域:
材料科学
·
机械工程
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF REFRACTORY METALS & HARD MATERIALS
·
2023
·
IF 3.6
Dongyang He,Hailang Liu,Zhuangzhi Wu,Dezhi Wang
The low ductility of refractory Mo-based materials limits their further processing and wide applications. To address this challenge, a composite strengthening and toughening strategy was proposed by the simultaneous addition of WC and La 2 O 3 . And a collaborative improvement of strength and ductility is achieved over the as-sintered Mo-WC-La 2 O 3 , exhibiting a total elongation (TE) of 33.63% and an ultimate tensile strength (UTS) of 611.33 MPa, about 50.27% and 24.76% larger than those of pure Mo, respectively. Furthermore, the corresponding microstructural features and tensile fracture behavior were also discussed to explore the improvement mechanism. And it is found that the enhancement should be attributed to the high relative density, grain refinement, generated substructures and secondary phase particle refinement. Moreover, the additional toughening mechanisms of crack deflection, particles pull-out and crack halt can also prevent crack extension, which helps to give full play to the potential ductility of Mo composites. This work provides a new pathway for manufacturing advanced Mo-based products with excellent strength-ductility balance.
研究领域:
材料科学
·
力学
✓ 已验证
产品关联
DOI
高影响因子
Metals
·
2024
·Vol. 14
·期 9
·981
·
IF 2.6
Jialie Liu,Junjie Xu,Chuntao Ge,Jie Pang,Weiliang Jin,Geir Martin Haarberg,Saijun Xiao
To enhance the anticorrosion properties of molybdenum metal in liquid zinc, this study successfully fabricated TiB2coatings on molybdenum substrates via the molten salt electrophoretic deposition technique and investigated their corrosion resistance in molten zinc. Initially, TiB2nanoparticles with a size ranging from 50 to 150 nm were synthesized using the borothermal reduction method in a molten NaF-AlF3bath at 1238 K. Subsequently, the electrophoretic deposition experiment was conducted under a cell voltage of 1.2 V (i.e., 0.6 V/cm) for a duration of 1 h in the melt containing TiB2nanoparticles, resulting in a uniform, continuous, and compact TiB2coating (35 μm thick) on the molybdenum substrate. Moreover, the corrosion resistance of the TiB2-coated molybdenum metal to molten zinc was tested through continuous immersion. After 120 h of immersion, the TiB2coating showed no signs of cracking or peeling off, successfully protecting the molybdenum metal substrate from corrosion by molten zinc. The results confirm that the molten salt electrophoretic deposition technique can be used to prepare TiB2coatings with good resistance to molten zinc corrosion on molybdenum metal.
研究领域:
材料科学
·
腐蚀与防护
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
INORGANIC CHEMISTRY
·
2021
·
IF 5.165
Yueyao Du,Zhifeng He,Fangwei Ma,Yuchen Jiang,Jiafeng Wan,Guang Wu,Yifu Liu
Recently, Mo-based metal catalysts are widely applied in the electrocatalytic nitrogen reduction reaction (NRR) due to the lower binding energy between the Mo atom and N atom. The design of a Mo-based catalyst@carbon heterostructure and the introduction of anion vacancies are effective measures to improve their NRR performance. In this research, the cross-linked Vo-MoO2@C (Vo means oxygen vacancies) heterostructure nanoparticles with rich oxygen vacancies are first synthesized via pectin assisted hydrothermal reaction followed by calcination and treating with NaBH4 solution. Vo-MoO2@C exhibits good electrocatalytic NRR performance with an ammonia yield rate of 9.75 μg h–1 mg–1 at −0.5 V (RHE) and a Faraday efficiency (FE) of 3.24% at −0.3 V (RHE) under ambient conditions.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Molecular Catalysis
·
2025
·
IF 4.9
Wei Wang,Rui Zhang,Jiaqing Li,Huai Liu,Wenlong Jia,Junhua Zhang,Dan Li,Lincai Peng
Furans are important scaffolds with applications in pharmaceuticals, polymers synthesis and biofuels. The direct production of new types of furans from glucose is therefore significant but remains a great challenge. Herein, we report a facile strategy to produce acetylfurans directly from glucose over MoCs-SiO 2 , with an increase in yield from 35.8 % to 81.4 % compared with pristine Mo-SiO 2 due to the facilitated C−C bond cleavage of glucose. The incorporation of Cs improved the dispersion of Mo species, induced the formation of partially reduced Mo, increased the Lewis acidity and glucose adsorption of the catalyst, and thus shifting the reaction selectivity from C−C coupling to cleavage. Kinetic studies further demonstrated the positive contribution of Cs as a promoter in lowering the activation energy of C−C bond cleavage. This study provides a promising strategy to broaden the range of furanic compounds derived from glucose for product-oriented biorefineries.
研究领域:
化学工程
·
生物催化
·
可再生资源利用
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2024
·
IF 7.4
Yangyang Bian,Yi Qiu,Jianfeng Zhang,Qiyu Meng,Li Wang,Shan Ni,Huizhou Liu,Liangrong Yang
The development of highly efficient adsorbents for the capture of 133 Cs and the removal of radioactive isotope 137 Cs from complex aqueous solutions is crucial for the chemical production and environmental remediation. Herein, Mo-based crystalline adsorbent with sub-nanometer (5.76 Å) channels was successfully prepared and used in electrochemically controlled Cs + separation process. Crystalline structures of MoIC (HNO 3 ) before and after adsorption of Cs + were clearly elucidated using powder X-ray diffractometer (PXRD). A more environmentally friendly electrochemical method was employed to achieve easy release and recapture of Cs + . Adsorption comparison experiments revealed that our material clearly outperforms the reported adsorbents for the removal or recovery of trace amount of Cs + (< 10 mg L −1 ). Furthermore, MoIC (HNO 3 ) also exhibited excellent selectivity for low concentration of Cs + over highly excess of competitive cations, such as Mg 2+ , Ca 2+ and K + , which are commonly distributed in brines. The maximum separation factors of Cs + /Mg 2+ , Cs + /Ca 2+ and Cs + /K + are 1.2 × 10 5 , 1.3 × 10 4 and 66, respectively. The remarkable selectivity can be attributed to the outstanding ion-sieving ability of sub-nanometer channels based on the differences in ionic radius and hydration energy of these cations. A real brine was introduced to further prove that one complete cycle of electrochemical adsorption and desorption can dramatically reduce the competing ions concentrations up to 980 times. We anticipate that our findings may give the prospect of opening up new path for the efficient separation of Cs + from brines using molybdenum-based adsorbent via electrochemically controlled process as a green and sustainable way.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF REFRACTORY METALS & HARD MATERIALS
·
2022
·
IF 4.804
Kai Li,Dongyang He,Hailang Liu,Zhuangzhi Wu,Dezhi Wang
Incoherent interphases and oxygen segregation at the grain boundaries (GBs) significantly deteriorate the strength of Mo-based alloys. In this study, a new additive, LaB 6 , was proposed to enhance the mechanical properties . It was found that LaB 6 reacted with the matrix to generate coherent La 2 O 3 , volatile B 2 O 3 and tiny MoB in situ during sintering. The addition of LaB 6 does not increase strength by itself, but can limit grain growth and construct a coherent interface between the as-obtained La 2 O 3 and Mo matrix. More importantly, the oxygen impurity is removed by B in the form of B 2 O 3 , which purifies the GBs. As a result, the as-sintered Mo-La-B billets present an extremely high ultimate tensile strength of 965 MPa, which is among the best recorded values for all sintered Mo-based alloys. The enhanced strength can be attributed to the refined grain size, coherent phase interface , and purified GBs.
研究领域:
材料科学
·
力学性能研究
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2023
·
IF 8.6
Lingchao Xu,Xin An,Junfeng She,Hongping Li,Linhua Zhu,Wenshuai Zhu,Huaming Li,Wei Jiang
Heterogeneous catalysts are usually constructed by immobilizing active species on appropriate supports. However, the dispersibility is difficult to precisely control. In this work, three representative Mo-based MOFs (Mo-MOFs) were constructed by assembling various organic linkers and MoO 3 , where the Mo atoms are homogeneously dispersed due to the coordination. The results illustrated that the obtained Mo-MOF-PI synthesized with 2-propyl imidazole as the ligands exhibited an extremely fast reaction rate, achieving 99.4% sulfur removal of DBT within only 12 min. Compared to other similar catalysts, Mo-MOF-PI showed much higher catalytic activity with a turnover frequency value of 19.2 h −1 . Moreover, it can be reused at least 20 times without a dramatic reduction in catalytic performance. Thus, the as-prepared Mo-MOF catalysts show great potential in large-scale industrial applications.
研究领域:
化学工程
·
催化材料
✓ 已验证
产品关联
DOI
高影响因子
JACS Au
·
2024
·
IF 8.5
Shuairen Qian,Tianying Dai,Kai Feng,Zhengwen Li,Xiaohang Sun,Yuxin Chen,Kaiqi Nie,Binhang Yan,Yi Cheng
Chemical looping ammonia synthesis (CLAS) is a promising technology for reducing the high energy consumption of the conventional ammonia synthesis process. However, the comprehensive understanding of reaction mechanisms and rational design of novel nitrogen carriers has not been achieved due to the high complexity of catalyst structures and the unrevealed relationship between electronic structure and intrinsic activity. Herein, we propose a multistage strategy to establish the connection between catalyst intrinsic activity and microscopic electronic structure fingerprints using density functional theory computational energetics as bridges and apply it to the rational design of metal nitride catalysts for lattice nitrogen-mediated ammonia production. Molybdenum-based nitride catalysts with well-defined structures are employed as prototypes to elucidate the decoupled effects of electronic and geometrical features. The electron-transfer and spin polarization characteristics of the magnetic metals are constructed as descriptors to disclose the atomic-scale causes of intrinsic activity. Based on this design strategy, it is demonstrated that Ni3Mo3N catalysts possess the highest lattice nitrogen-mediated ammonia synthesis activity. This work reveals the structure–activity relationship of metal nitrides for CLAS and provides a multistage perspective on catalyst rational design.
研究领域:
化学工程
·
材料科学
·
催化科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
BIOTECHNOLOGY PROGRESS
·
2022
·Vol. 38
·期 4
·e3256
·
IF 2.909
Duanhao Wang,Meijing Guo,Jiachen Li,Binglin Li,Jiao Wang
Six kinds of Mo-basing nanomaterials (MoO 3 , MoO 3 @Ru, Mo-PDA, MoP C , MoP, CNT@MoS 2 ) were successfully synthesized, which were employed as carriers to immobilize phospholipase A 1 (PLA1) for the hydrolysis of phospholipids (PLs). PLA1 was immobilized by a simple adsorption-precipitation-cross-linking to form an “enzyme net” covering on nanoparticles. The greatest advantage of these nanoparticles was their strong hydrophilic surface. It not only permitted their dispersion in the aqueous phase, but also showed the strong affinity for PLs in the organic phase, because amphiphilic PLs had the polar head group and higher hydrophilicity than other oils components. Michaelis–Menten analysis revealed that higher catalytic activity and enzyme−substrate affinity were observed in several immobilized PLA1 than its free form. MoO 3 was confirmed to be the best candidate for carrier. The highest specific activity of MoO 3 -immobilized PLA1 reached 43.1 U/mg, which was about 1.8 times higher than that of free PLA1 (24.4 U/mg). In addition, the stability and recycling were also enhanced. The robust immobilized PLA1 was prepared in this work, showing great potential for the enzymatic degumming.
研究领域:
生物化学
·
纳米生物学
·
食品科学
✓ 已验证
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2025
·
IF 7.9
Wei Yang,Wenbin Wang,Sha Deng,Qingyun Ji,Yunlong Guo,Tao Long
Non precious metal materials have attracted much attention in oxygen evolution reactions (OER) due to their abundant reserves and low cost. However, due to their thermodynamic instability, they typically exhibit high reaction barriers, poor stability, and fewer active sites. In response to this challenge, this paper studied the in-situ growth of Ni 2.86 Te 2 and Mo 6 Te 8 multiphase telluride catalysts on foam nickel molybdenum (NM) substrates, and revealed their excellent catalytic performance in OER. The research results show that the catalyst has an overpotential of 300 mV and a Tafel slope of 78.61 mV·dec −1 at a current density of 20 mA cm −2 , and its performance is comparable to that of the precious metal catalyst RuO 2 . After 60 h of electrolysis, the catalyst showed no significant deactivation and exhibited good stability. Density functional theory (DFT) calculations further indicate that the electronic coupling between Ni 2.86 Te 2 and Mo 6 Te 8 enhances charge transfer, reduces the energy barrier of the rate determining step (RDS), and the abundant active sites on local atomic doping on the surface significantly enhance OER activity, providing new ideas for developing highly active and stable non precious metal catalysts for oxygen evolution.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
·
2022
·
IF 6.044
Dezhi Wang,Dongyang He,Kai Li,Zhuangzhi Wu
The strength enhancement is critical for the application exploration of Mo-based materials. In this work, a secondary phase of WC is introduced into the Mo matrix, and the corresponding phase, microstructure and mechanical properties have been studied. It is found that the addition of WC particles can significantly improve the mechanical properties, leading to a high ultimate tensile strength (UTS) of 591.5 MPa and a hardness of 242.7 HV over the sintered Mo–12%WC composite, which are about 21.2% and 49.5% higher than those of pure Mo, respectively. During the sintering, the additive WC particles react with the Mo matrix to in-situ generate W and Mo 2 C, and the former is dissolved into the Mo matrix to exhibit solid solution strengthening. Besides, the latter hinders the migration of grain boundaries (GBs) to limit the grain growth of Mo, resulting in smaller grain size. More importantly, the Mo 2 C ( 1 ‾ 2 ‾ 1 ) can gain coherent interfaces with Mo ( 1 1 ‾ 0) to intensify the phase boundary. This work paves a way for the design of high-performance composites through the in-situ reinforcement of decomposable additives.
研究领域:
材料科学
·
力学
✓ 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）