發(fā)布時(shí)間：2018-01-24 04:51

  本文關(guān)鍵詞： 納米陣列 多級(jí)結(jié)構(gòu) 過渡金屬氧化物 多相催化 超級(jí)電容器　出處：《北京化工大學(xué)》2015年碩士論文　論文類型：學(xué)位論文

【摘要】：隨著納米科學(xué)技術(shù)的發(fā)展,納米陣列材料得到了廣泛的關(guān)注。由于具有諸多的結(jié)構(gòu)優(yōu)勢(shì)(特定的暴露晶面、尺寸可調(diào)、與基底粘結(jié)性好等)納米陣列材料在場(chǎng)發(fā)射材料、表界面材料、電化學(xué)電極、多相催化劑、傳感器等領(lǐng)域有著重要的應(yīng)用。其中,基于復(fù)合過渡金屬氧化物的納米陣列,具有價(jià)格低廉、性質(zhì)穩(wěn)定、結(jié)構(gòu)優(yōu)越等特點(diǎn),并且由于協(xié)同作用的存在,其往往表現(xiàn)出與相應(yīng)單體氧化物不同的理化性能,從而具有重要的研究和應(yīng)用價(jià)值。本論文中通過液相化學(xué)沉積法對(duì)不同復(fù)合過渡金屬氧化物納米陣列進(jìn)行可控合成,研究了它們的生長(zhǎng)過程和催化及電化學(xué)性能。該研究為揭示形貌調(diào)控和性能優(yōu)化的關(guān)系提供了有價(jià)值的參考和依據(jù)。論文的主要研究?jī)?nèi)容如下：1、利用一步水熱共沉積的方法成功合成了NiCoFe-LDH納米片陣列,以其作為前驅(qū)體通過煅燒過程得到NiCoFe尖晶石氧化物納米片陣列,其作為結(jié)構(gòu)化催化劑對(duì)苯乙烯的選擇性氧化反應(yīng)表現(xiàn)出很高的催化活性(轉(zhuǎn)化率72%,苯甲醛選擇性64%)。通過對(duì)比試驗(yàn)證明,除了超薄多孔納米片陣列具有較大的比表面積和結(jié)構(gòu)穩(wěn)定性之外,Co元素的摻雜對(duì)催化活性的提高起了重要作用,主要?dú)w因于Co3+的摻雜為催化劑提供了更多的3+價(jià)活性位點(diǎn)。2、發(fā)展了一步水熱法合成系列多級(jí)納米陣列的方法�；谙嚓P(guān)的實(shí)驗(yàn)探究,我們提出了一種在堿性水熱條件下使過渡金屬離子共沉積形成多級(jí)納米陣列的方法。其主要基于以下三點(diǎn)：①當(dāng)兩種過渡金屬離子在堿性水熱體系中沉積生成多級(jí)結(jié)構(gòu)時(shí),其氫氧化物Ksp較小者先沉積,Ksp較大者后沉積。②過渡金屬離子在特定堿性體系下沉積形成的氫氧化物或堿式碳酸化合物具有確定的晶體類型和形貌特征。③晶格匹配的沉積物可以進(jìn)行二級(jí)生長(zhǎng)。通過查取金屬氫氧化物的相關(guān)數(shù)據(jù),即可有目的性的合成相應(yīng)的多級(jí)納米陣列。在該方法的指導(dǎo)下,我們成功合成了多種過渡金屬離子摻雜的多級(jí)納米陣列(Zn2+/Ni2+,Co2+/Ni2+,Mn2+/Ni2+,Mn2+/Zn2+等),證明了該方法的有效性。3、通過一步水熱法合成了ZnO/NiO復(fù)合金屬氧化物多級(jí)介孔納米陣列,研究了其生長(zhǎng)過程。證明了“Zn2+先沉積成柱,Ni2+后續(xù)沉積成片”的生長(zhǎng)過程,其主要?dú)w因于Zn(OH)2和Ni(OH)2在相應(yīng)條件下的溶度積不同。通過調(diào)控Zn2+/Ni2+的投料比例,我們還得到了ZnO/NiO納米片和納米棒陣列。對(duì)三者進(jìn)行電化學(xué)性能測(cè)試表明,ZnO/NiO復(fù)合金屬氧化物多級(jí)納米陣列表現(xiàn)出比另外兩種一維和二維陣列材料更加優(yōu)異的超電容性能：放電電流密度為5 mA cm-2時(shí),面積容量達(dá)到了6.23F·cm-2(1512.14F·g-1),倍率特性為69.3%(放電電流為30mA·cm-2)。主要?dú)w因于該多級(jí)結(jié)構(gòu)具有更大的比表面積、孔隙率以及暴露更多的活性位點(diǎn)。
[Abstract]:With the development of nanometer science and technology, nano-array materials have been paid more and more attention. Because of its many structural advantages (specific exposed crystal plane, adjustable size). Nano-array materials such as field emission materials, surface interface materials, electrochemical electrodes, multiphase catalysts, sensors and other fields have important applications. Nanoarrays based on composite transition metal oxides have the advantages of low cost, stable properties and superior structure, and because of the existence of synergy. Its physical and chemical properties are often different from the corresponding monomer oxides. In this thesis, different composite transition metal oxide nanoarrays were synthesized by liquid phase chemical deposition. The growth process and catalytic and electrochemical properties of these compounds were studied. This study provides a valuable reference and basis for revealing the relationship between morphology regulation and performance optimization. The main contents of this paper are as follows: 1. The NiCoFe-LDH nanocrystalline arrays were successfully synthesized by one step hydrothermal co-deposition, and NiCoFe spinel oxide nanoarrays were obtained by calcination process. As a structured catalyst, it exhibited high catalytic activity for the selective oxidation of styrene (the conversion of 7222g, the selectivity of benzaldehyde was 64%). In addition to the large specific surface area and structural stability of ultrathin porous nanoarrays, doping of Co plays an important role in the improvement of catalytic activity. The main reason is that the doping of Co3 provides more 3 valence active sites for the catalyst and develops the method of one-step hydrothermal synthesis of a series of multistage nanoarrays. We propose a method for codeposition of transition metal ions into multilevel nanoarrays under alkaline hydrothermal conditions, which is based on the following three points:. 1 when two transition metal ions are deposited in alkaline hydrothermal system to form multilevel structures. The hydroxide Ksp was deposited first. The hydroxide or basic carbonate formed by the later deposition of 2 transition metal ions in a specific alkaline system with larger Ksp can be used to determine the crystal type and morphologic characteristics of the lattice-matched sediments. Secondary growth. The data of metal hydroxide were obtained. Under the guidance of this method, we successfully synthesized a variety of transition metal ions doped multilevel nanoscale arrays (Zn2 / Ni2). The effectiveness of this method is proved by Co2 / Ni2 / Ni2 / Ni2 / Zn2 / Zn2 et al. The multistage mesoporous nanoarrays of ZnO/NiO composite metal oxides were synthesized by one step hydrothermal method, and the growth process was studied. The growth process of Ni2 subsequent deposition "is mainly attributed to the different solubility product of Zn(OH)2 and Ni(OH)2 under the corresponding conditions, by adjusting the feed ratio of Zn2 / Ni2." ZnO/NiO nanoparticles and nanorods arrays were also obtained. The electrochemical properties of the three nanorods were tested. ZnO/NiO composite metal oxide multistage nanoarrays exhibit better supercapacitor performance than the other two kinds of materials: when the discharge current density is 5 Ma cm-2. The area capacity reached 6.23F 路cm-2(1512.14F 路g-1). The ratio characteristic is 69.3 (the discharge current is 30mA 路cm ~ (-2)). The main reason is that the multistage structure has larger specific surface area, porosity and more active sites exposed.
【學(xué)位授予單位】：北京化工大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2015
【分類號(hào)】：TB383.1

【共引文獻(xiàn)】

相關(guān)期刊論文 前3條

1 李玉魁;李曉荃;劉興輝;盧文科;;Fabrication Research and Property of Enhanced Petaling Cold Cathode with Carbon Nanotube[J];Journal of Donghua University(English Edition);2013年02期

2 王福全;董長(zhǎng)昆;李得天;;碳納米管場(chǎng)發(fā)射陰極制備技術(shù)與應(yīng)用進(jìn)展[J];材料導(dǎo)報(bào);2013年21期

3 王鳳歌;李玉魁;盧文科;;Enhanced Field Emission Performance and Better Emitting Current Stability of Mixed Multilayer Carbon Nanotube Cathode[J];Journal of Donghua University(English Edition);2015年03期

相關(guān)碩士學(xué)位論文 前3條

1 孫赫;氮摻雜炭納米微球的制備、表征及在有機(jī)廢水處理中的應(yīng)用[D];吉林大學(xué);2014年

2 孫曉蕾;碳納米管負(fù)載SnO_2納米顆粒乙醇?xì)饷籼匦匝芯縖D];黑龍江大學(xué);2014年

3 王福全;碳納米管場(chǎng)發(fā)射技術(shù)及電真空器件研究[D];溫州大學(xué);2014年

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本文編號(hào)：1459215