2022年铁钴镍基二元合金设计方案铁钴镍基二元合金微纳米结构控制合成磁学及催化性能 .pdf

《2022年铁钴镍基二元合金设计方案铁钴镍基二元合金微纳米结构控制合成磁学及催化性能 .pdf》由会员分享，可在线阅读，更多相关《2022年铁钴镍基二元合金设计方案铁钴镍基二元合金微纳米结构控制合成磁学及催化性能 .pdf（8页珍藏版）》请在淘文阁 - 分享文档赚钱的网站上搜索。

1、个人资料整理仅限学习使用铁钴镍基二元合金论文：铁钴镍基二元合金微纳M结构的控制合成、磁学及催化性能【中文摘要】磁性合金材料作为一类重要的功能材料, 引起了科学家的广泛关注 , 并在很多领域得到广泛的应用, 如: 磁流体、催化、生物科技和生物医药、磁共振成像、数据存储、环境治理等领域。而纳 M材料的性能常常受其尺寸、形貌和组成的影响, 因此, 可控制合成磁性微纳 M材料与性能研究成为了化学和材料学研究的重要领域之一。本论文旨在发展不同的合成方法制备具有不同形貌、尺寸和组成的铁钴镍基二元合金微纳M材料, 同时, 对其形成机理、相关磁学性能和在对硝基苯酚【英文摘要】 Magnetic alloys

2、materials are very important functional materials, which have attracted extensive attention because of their special physical, chemical properties and their potential applications in ferrofluids, magnetic resonance imaging, biotechnology, biomedicine, data storage, catalytsis, and environmental reme

3、diation, etc., and which strongly depended on their size, morphology, composition, and structure etc. In this thesis, we focused on developing different methods to synthesize magnetic binary alloys micro-/nanostructures based on Fe, Co and Ni with different morphologies, sizes, 精选学习资料 - - - - - - -

4、- - 名师归纳总结 - - - - - - -第 1 页，共 8 页个人资料整理仅限学习使用and compositions. At the same time, their formation mechanism, magnetic properties, and catalytic applications in reduction of 4-Nitrophenol were studied. The main contents and major results are given as follows:1. Uniform-sized, monodisperse, and singl

5、e crystalline 3-dimensional NiCo2 dendritic microstructures were successfully synthesized in high yield by a simple and facile solution phase route in presence of CTAB. By adjusting the experimental parameters NiCo alloys nanostructures with different morphologies, sizes, and compositions were contr

6、ollable synthesized, at the same time, the formation mechanism was investigated. While NiCo2 alloys micro-structure with shapes of sphere-like and flower-like were prepared by hydrothermal and solvothermal methods, respectively. Magnetic measurements revealed that all of the NiCo2 alloys obtained ar

7、e ferromagnetic at room temperature. The saturation magnetization value of the Ni33.8Co66.2 dendrites 163.55 emu/g） is lower than that of the Ni32.3Co67.7 spheres 212.29 emu/g） and Ni33.4Co66.6 flower-likes have been used as reusable heterogeneous catalysts to reduce 4-nitrophenol 4-NP）into 4-aminop

8、henol 4-AP） by NaBH4. From the average reaction rate constants at three different temperatures, we determined the activation energy, the entropy of activation, and the pre-exponential factor for each shape of NiCo2 alloys. The kinetic data indicate that Ni33.8Co66.2 dendrites are catalytically more

9、active than that of both the Ni33.4Co66.6 flower-likes and Ni32.3Co67.7 spheres probably due to its largest surface-to-volume ratio and surface areas.2. The Ni-based metals, such as Ni, and FeNi alloy nanostructures with different shapes were synthesized by solvothermal method in polyol system. The

10、reaction parameters such as reaction time, the concentration of NaOH, temperature, solvent, and the initial concentration of metals ions that affected the morphology of FeNi alloys were investigated systematically. When we changed the type of solvents, the Ni nanostructures with chain-like were obta

11、ined, and the possible formation mechanism was also discussed. Magnetic data show that all of the Ni and FeNi2 alloys obtained are ferromagnetic at room temperature. The 精选学习资料 - - - - - - - - - 名师归纳总结 - - - - - - -第 3 页，共 8 页个人资料整理仅限学习使用saturation magnetization value of the Fe34.8Ni65.2 spheres wit

12、h size of ca. 300 nm 174.62 emu/g） is higher than that of the Fe34.1Ni65.9 spheres with size of ca. 230 nm 166.71 emu/g） and Fe33.5Ni66.5 spheres with size of ca. 170 nm 160.05 emu/g ）, but the Fe33.5Ni66.5 spheres ca. 170 nm）exhibit an enhanced coercivity value. The saturation magnetization value o

13、f the chain-like Ni nanostructures 68.3 emu/g ） is lower than that of flower-like Ni nanostreutures 84.9 emu/g）, but all higher than that of the bulk nickel 55 emu/g）. Especially, the flower-like Ni nanostructures exhibit an enhanced coercivity value ca. 204.81 Oe）. At last, the FeNi2 alloys with th

14、ree different sizes were applied to reduce the 4-Nitrophenol to 4-Aminophenol by NaBH4 in aqueous solution, and the reaction rate constants were obtained. The kinetic data indicate that Fe33.5Ni66.5 nanospheres ca. 170 nm） are catalytically more active than that of both the Fe34.1Ni65.9 nanospheres

15、ca. 230 nm） and Fe34.8Ni65.2 nanospheres ca. 300 nm ） probably attribute to its smallest size, which induces the largest surface-to-volume ratio and surface areas. The BET3. Crystalline FeCo alloys Fe59Co41, Fe37Co63 ） nanoparticles in diameter of 6?12 nm 精选学习资料 - - - - - - - - - 名师归纳总结 - - - - - -

16、-第 4 页，共 8 页个人资料整理仅限学习使用were synthesized by reduction of FeCl3 with hydrazine under ultrasonic wave, which is a simple, low-cost, surfactant-free route, and may stimulate technological interests. The reaction parameters such as temperature, the total concentration of Fe3+ + Co2+, and the initial rat

17、io of Fe3+/Co2+ that affected the FeCo sizes and morphologies were investigated systematically. As-synthesized Fe59Co41 nanocrystallite shows excellent soft magnetic behaviour with high saturation magnetization up to 216.2 emu/g that is comparable with that of bulk Fe and Fe60Co40 alloy, and could h

18、ave applications in catalysis, biotechnology, and magnetic storage devices.4. The metals/r-graphene and alloys/r-graphene hybrid materials, such as Ni/r-graphene, Co/r-graphene, Cu/r-graphene, NiCo/r-graphene, FeCo/r-graphene, FeNi/r-graphene, CoCu/r-graphene and NiCu/r-graphene hybrid materials wer

19、e successfully synthesized by a fiacle two steps method used hydrazine as reduction reagent. The samples were characterizated by SEM, TEM, HRTEM, XRD, EDX, and ICP, respectively, the results shown that the nanoparticles were uniform dispersed on the surface of the graphene sheets. The reaction param

20、eters such as reaction time, the concentration of metals ions, 精选学习资料 - - - - - - - - - 名师归纳总结 - - - - - - -第 5 页，共 8 页个人资料整理仅限学习使用the modified of graphene, and the added sequence of the materials that affected the formation of hybrid materials were investigated systematically, based on which possib

21、le formation mechanism for the hybrid materials was proposed. The room temperature magnetic properties were characterizated by SQUID MPMS XL-7）, the metal or alloy/r-graphene hybrid materials exhibited an enhanced saturation magnetization or coercivity. At last, the reduction of 4-NP to 4-AP were ca

22、rried out used five different materials as catalysts. The rate constants of the five catalysts is 5.8210-3 S-1S1, Ni/r-graphene）, 4.6310-3 S-1S2, Ni/r-graphene）, 4.95 10-3 S-1S3, Ni/r-graphene）, 2.60 10-3 S-1r-graphene）, 3.50 10-3 S-1Ni nanoparticles）, 4.15 10-3 S-1Co_(66.6 合金结构的分析38-392.3.3 球状Ni_(3

23、2.3Co_(67.7 合金结构的分析39-402.3.4 不同形貌的NiCo_2合金微结构的磁学性能40-412.4 不同形貌的镍钴合金在对硝基苯酚催化中的应用41-452.4.1 催化实验412.4.2 催化可行性分析以及催化过程的跟踪41-422.4.3 催化结果与讨论42-452.5 本章小结45-46参考文献46-57第三章高饱和磁化强度的镍基金属材料的溶剂热合成及其催化性能研究57-813.1 引言 57-583.2 实验部分58-593.2.1 试剂和仪器583.2.2 镍基金属的制备583.2.3 样品的表征58-593.2.4 催化性能593.3 结果与讨论59-723.3.

24、1 FeNi 合金纳 M结构的控制合成59-663.3.2 镍纳 M结构的表征66-精选学习资料 - - - - - - - - - 名师归纳总结 - - - - - - -第 7 页，共 8 页个人资料整理仅限学习使用673.3.3 Fe-Ni 和 Ni 纳 M材料的磁学性能67-703.3.4 不同尺寸的 Fe-Ni 合金的催化性能70-723.4 本章小结72-73参考文献73-81第四章超声法合成高饱和磁化强度的铁钴合金纳M晶 81-954.1 引言 814.2 实验部分81-824.2.1 试剂和仪器 81-824.2.2 Fe-Co 合金的制备824.2.3 样品的表征824.3

25、结果与讨论82-884.3.1 Fe-Co 合金的合成和结构分析 82-874.3.2 样品的室温磁性能分析87-884.4 本章小结88-89参考文献89-95第五章 石墨烯复合磁性材料的合成、形成机理及其磁学性能95-1215.1 引言 95-965.2 实验部分96-985.2.1 试剂与仪器965.2.2 样品制备96-985.2.3 催化性能985.2.4 样品表征985.3 结果与讨论98-1155.3.1 Ni 纳 M粒子和 Ni/r-graphene 样品的结构和形貌分析98-1105.3.2 磁性金属及合金 / 石墨烯复合纳 M材料的磁学性能110-1135.3.3 不同负载密度的 Ni/r-graphene 复合材料在对硝基苯酚还原中的应用113-1155.4 本章小节115-117参考文献117-121第六章全文总结与展望121-1246.1 结论 121-1236.2 展望 123-124科研成果及所获奖励124-125致谢125精选学习资料 - - - - - - - - - 名师归纳总结 - - - - - - -第 8 页，共 8 页