發(fā)布時間：2018-04-18 20:34

  本文選題：模板法 + 空心微球��； 參考：《安徽大學(xué)》2011年碩士論文

【摘要】：近年來,空心微球在催化、化妝品、藥物和基因傳遞、氫氣的生產(chǎn)和存儲、光子學(xué)、光電和充電電池方面的廣泛應(yīng)用,引起了人們對其制備和特性研究的極大興趣。而在諸多制備空心微球的方法中,模板法的使用最為廣泛,因為理論上只要找到一種合適的模板材料,就可以制備尺寸、外形、化學(xué)組分可控的空心結(jié)構(gòu)。因此,深入而細(xì)致地研究模板法制備空心微球的原理及工藝,具有非�，F(xiàn)實的應(yīng)用價值。由于氧化鋅和鐵氧體材料在電子器件、半導(dǎo)體材料、生物工程、光電子學(xué)、微波吸收等方面的重要應(yīng)用,探索和制備具有空心結(jié)構(gòu)的氧化鋅和鐵氧體材料是目前材料學(xué)、光學(xué)、電磁學(xué)、生物學(xué)、化學(xué)等領(lǐng)域中的研究熱點。 本文利用模板法制備了空心結(jié)構(gòu)的ZnO微球和CoFe2O4微球。圍繞著空心微球的制備,文章著重討論了制備工藝過程對微球結(jié)構(gòu)及形貌的影響,論述了不同燒結(jié)溫度對CoFe2O4微球磁學(xué)特性的影響。主要研究內(nèi)容如下： 1.利用水熱法制備膠體碳球模板,并對其結(jié)構(gòu)形貌進(jìn)行表征。表征結(jié)果顯示,模板顆粒為球形、非晶顆粒,且尺寸均勻。 2.采用模板法制備了具有纖鋅礦結(jié)構(gòu)的多晶ZnO空心微球,系統(tǒng)的研究了不同工藝參數(shù)對空心微球結(jié)構(gòu)及形貌的影響。當(dāng)燒結(jié)溫度不低于450℃時,可以獲得成分純凈的ZnO空心球；通過改變模板顆粒在Zn2+離子溶液中的靜置時間,可以對空心微球的尺寸及表面形貌進(jìn)行調(diào)控；Cl-離子及N03-離子的加入,會對ZnO空心微球的形貌有著重要的影響 3.利用水熱法制備了具有尖晶石結(jié)構(gòu)的鈷鐵氧體多晶顆粒,詳盡的研究了水熱反應(yīng)溫度及反應(yīng)時間對其結(jié)構(gòu)及磁性能的影響。不同的反應(yīng)溫度會對鈷鐵氧體顆粒的成分產(chǎn)生重要影響。隨著反應(yīng)溫度的升高,鈷鐵氧體顆粒的磁性增強；通過改變水熱反應(yīng)時間,可以對鈷鐵氧體的飽和磁化強度、矯頑力、剩余磁化強度進(jìn)行調(diào)節(jié)。我們認(rèn)為,O2-離子與磁性陽離子間的電子軌道雜化是產(chǎn)生鈷鐵氧體晶核的誘因。 4.通過模板法制備出具有尖晶石結(jié)構(gòu)的多晶鈷鐵氧體空心微球,深入而細(xì)致的研究了不同燒結(jié)溫度對空心微球的結(jié)構(gòu)、形貌及磁性能的影響。通過改變燒結(jié)溫度,鈷鐵氧體空心微球的形貌發(fā)生變化。當(dāng)溫度達(dá)到550℃及以上時,微球逐漸由空心結(jié)構(gòu)轉(zhuǎn)變?yōu)槎嗫捉Y(jié)構(gòu)。實驗還發(fā)現(xiàn),當(dāng)燒結(jié)溫度達(dá)到450℃時,微球中出現(xiàn)α-Fe203反鐵磁相。通過分析,我們認(rèn)為Fe3+[(Co1_xFex)2+Fe3+]04的生成是導(dǎo)致相變發(fā)生及樣品磁性能變化的主要原因。
[Abstract]:In recent years, the wide application of hollow microspheres in catalysis, cosmetics, drug and gene transfer, hydrogen production and storage, photonics, photoelectricity and rechargeable batteries has attracted great interest in their preparation and characterization.Among the many methods of preparing hollow microspheres, template method is the most widely used, because in theory, as long as a suitable template material is found, the size, shape and chemical composition of the hollow structure can be controlled.Therefore, it is of great practical value to study the principle and technology of hollow microspheres prepared by template method.Because of the important applications of zinc oxide and ferrite materials in electronic devices, semiconductor materials, bioengineering, optoelectronics, microwave absorption and so on, the exploration and preparation of zinc oxide and ferrite materials with hollow structure are current materials.The research focus in electromagnetism, biology, chemistry and so on.In this paper, hollow ZnO microspheres and CoFe2O4 microspheres were prepared by template method.Around the preparation of hollow microspheres, the influence of the preparation process on the structure and morphology of the microspheres was discussed, and the effects of different sintering temperatures on the magnetic properties of CoFe2O4 microspheres were discussed.The main contents of the study are as follows:1.Colloidal carbon sphere template was prepared by hydrothermal method and its structure and morphology were characterized.The results showed that the template particles were spherical, amorphous and uniform in size.2.Polycrystalline ZnO hollow microspheres with wurtzite structure were prepared by template method. The effects of different process parameters on the structure and morphology of hollow microspheres were studied systematically.When the sintering temperature is not lower than 450 鈩，

本文編號：1769975