【摘要】：材料是人類賴以生存和發(fā)展的物質(zhì)基礎(chǔ)，隨著生產(chǎn)的高速發(fā)展以及由此帶來(lái)的環(huán)境、能源問(wèn)題的出現(xiàn)，新材料發(fā)展的重點(diǎn)已從結(jié)構(gòu)材料轉(zhuǎn)向功能材料。過(guò)渡金屬氧化物，尤其是第四周期過(guò)渡金屬氧化物，它們以其獨(dú)特的化學(xué)、物理性質(zhì)在氣體傳感、光電器件、電化學(xué)儲(chǔ)能以及催化等領(lǐng)域都發(fā)揮著無(wú)可替代的作用。近年來(lái)，納米科技的快速發(fā)展為功能材料的深入研究和材料微觀結(jié)構(gòu)的設(shè)計(jì)注入了新的元素，人們?cè)桨l(fā)意識(shí)到功能材料的結(jié)構(gòu)與功能之間存在著密切的聯(lián)系。為了實(shí)現(xiàn)材料功能優(yōu)化的目標(biāo)，人們主要通過(guò)摻雜或復(fù)合來(lái)實(shí)現(xiàn)材料的組成調(diào)控，通過(guò)設(shè)計(jì)合成多孔結(jié)構(gòu)、多級(jí)結(jié)構(gòu)、活性晶面暴露以及納米化等結(jié)構(gòu)形態(tài)來(lái)實(shí)現(xiàn)材料微觀結(jié)構(gòu)的調(diào)控。本論文以第四周期過(guò)渡金屬（Co、Ni、Cu和Zn）的氧化物為研究對(duì)象，以多元醇為反應(yīng)體系，以優(yōu)化這類氧化物材料的氣體傳感和催化水氧化反應(yīng)性能為目標(biāo)，系統(tǒng)地開(kāi)展了相應(yīng)材料的化學(xué)組成和微觀結(jié)構(gòu)調(diào)控研究。 本論文主要包括以下內(nèi)容： 一、利用水和乙二醇混合溶劑的方法成功制備了多孔Cu2O/CuO立方體復(fù)合材料。在前驅(qū)體形成過(guò)程中，乙二醇既作溶劑，，也作還原劑，致使獲得的前驅(qū)體中存在兩種價(jià)態(tài)的銅。通過(guò)控制煅燒處理溫度，可以控制產(chǎn)物Cu2O/CuO復(fù)合材料中CuO與Cu2O比例，而有機(jī)成分的分解及氣體的生成則進(jìn)一步導(dǎo)致多孔結(jié)構(gòu)的形成。該復(fù)合材料對(duì)丙酮?dú)怏w有很好的響應(yīng)，350oC煅燒后得到的復(fù)合材料對(duì)丙酮?dú)怏w的敏感性能最好，且明顯優(yōu)于商業(yè)CuO。當(dāng)丙酮濃度為500ppm時(shí)，其響應(yīng)值是商業(yè)CuO的4.3倍。進(jìn)一步通過(guò)TPD測(cè)試手段驗(yàn)證了材料與不同氣體之間的相互作用，從而解釋了復(fù)合材料氣敏選擇性的本質(zhì)原因。 二、同樣采用水和乙二醇的混合溶劑，我們制備出由多孔納米片組裝形成的CdO/ZnO微球。研究發(fā)現(xiàn)元素Cd、Zn和O在微球中是均勻分布的，而且通過(guò)高分辨透射電鏡可以清晰地觀察到CdO和ZnO的界面。我們?cè)敿?xì)研究了該材料對(duì)乙醇的敏感特性，發(fā)現(xiàn)CdO的引入顯著提高了ZnO材料對(duì)乙醇的響應(yīng)程度，當(dāng)Cd：Zn=7.5：100時(shí)，響應(yīng)值最高，是單一ZnO材料的7倍，而且檢測(cè)極限達(dá)到了0.5ppm，優(yōu)于商業(yè)ZnO的2ppm。我們認(rèn)為CdO促進(jìn)ZnO氣敏性能提高的原因在于CdO擁有大量的氧空穴，有利于氧分子在復(fù)合材料表面的吸附，增加了材料表面吸附氧的數(shù)量。另外CdO的低電阻特性促使電子易于傳輸，有利于檢測(cè)到電阻變化。 三、采用溶劑熱方法，在甘油、異丙醇混合溶劑中合成鎳甘油鹽微球，然后將鎳甘油鹽和硫酸亞鐵混合，在水熱條件下合成了高比表面積的Ni-Fe LDH材料，這些LDH材料表現(xiàn)出優(yōu)異的電催化水氧化性能，其中，當(dāng)Fe：Ni=0.52：1（ICP測(cè)試得到）時(shí)，性能最優(yōu)，電流密度為10mA/cm2，過(guò)電勢(shì)僅為344mV。所得材料的比表面積高，表面的活性位點(diǎn)多，并且多孔結(jié)構(gòu)有利于電子和物質(zhì)的傳輸，對(duì)催化水氧化反應(yīng)活性的提高有積極作用。更重要的是Fe3+取代Ni(OH)2中的Ni2+形成LDH結(jié)構(gòu)，F(xiàn)e擁有更高的結(jié)合能，有利于電催化水氧化反應(yīng)進(jìn)行。我們認(rèn)為，該合成思路可以擴(kuò)展到其它具有不同組成和高比表面LDH材料的制備。 四、首先通過(guò)溶劑熱方法合成了1，3丙二醇鈷前驅(qū)體，經(jīng)過(guò)煅燒該前驅(qū)體合成出多孔核殼的Co3O4八面體材料，其構(gòu)筑單元為5nm的納米粒子，且該材料比表面積高達(dá)190m2/g。我們對(duì)該材料在“光敏化劑-過(guò)硫酸鹽”體系下進(jìn)行了光催化水氧化性能的測(cè)試，發(fā)現(xiàn)其產(chǎn)氧速率可以達(dá)到~211.5μmol g-1min-1，約是商業(yè)Co3O4催化活性的18倍。由于緩沖溶液中的Na2SiF6發(fā)生水解，生成的氧化硅覆蓋在Co3O4材料表面，減少了催化材料的活性位點(diǎn)，因此該材料經(jīng)過(guò)長(zhǎng)時(shí)間催化反應(yīng)后，活性會(huì)有所下降，這表明該反應(yīng)體系還需要進(jìn)一步完善。
[Abstract]:The material is the material base of human existence and development. With the high-speed development of production and the environment and energy problems brought by it, the development of new materials has shifted from the structural material to the functional material. The transition metal oxides, especially the fourth periodic transition metal oxides, play an irreplaceable role in the fields of gas sensing, photoelectric devices, electrochemical energy storage and catalysis in their unique chemical and physical properties. In recent years, the rapid development of nano-technology has injected new elements into the research of functional materials and the design of the micro-structure of materials, and people have become more aware of the close relationship between the structure and function of the functional materials. In order to achieve the objective of material function optimization, the composition regulation of the material is mainly realized by doping or compounding, and the micro-structure of the material can be controlled by designing a structure such as a synthetic porous structure, a multi-stage structure, an active crystal face exposure and a nano-chemical structure. In this paper, the oxide of the transition metals (Co, Ni, Cu and Zn) in the fourth period was used as the research object, and the polyol was used as the reaction system to optimize the gas sensing and catalytic water oxidation reaction performance of the class of oxide materials. The chemical composition and micro-structure control of the corresponding materials are systematically carried out. The thesis mainly includes the following Content: 1. The porous Cu2O/ CuO cube was successfully prepared by the method of water and glycol mixed solvent. in that proces of the formation of the precursor, ethylene glycol is both a solvent and a reducing agent, so that the obtained precursor is present in two The ratio of CuO to Cu2O in the product Cu2O/ CuO composite can be controlled by controlling the temperature of the sintering treatment, and the decomposition of the organic components and the formation of the gas further lead to the porous. The composite material has good response to the acetone gas, Commercial CuO. The response value is commercial CuO when the acetone concentration is 500ppm and the interaction between the material and the different gases is further verified by the TPD test method, so that the gas-sensitive selectivity of the composite material is explained. the essential reason for this is that, in the same way, a mixed solvent of water and ethylene glycol is used, and the C formed by the assembly of the porous nanosheets is prepared. The results show that the elements Cd, Zn and O are uniformly distributed in the microball, and the Cd, Zn and O can be clearly observed through the high-resolution transmission electron microscope. The sensitivity of the material to ethanol was studied in detail. It was found that the introduction of CdO significantly improved the response of the ZnO material to the ethanol. When the Cd: Zn = 7.5: 100, the response value was the highest, which was 7 times that of the single ZnO material, and the detection limit reached 0. 5ppm, which was superior to the commercial. The reason for the improvement of the performance of CdO is that the CdO has a large number of oxygen holes, which is beneficial to the adsorption of the oxygen molecules on the surface of the composite material and the increase of the material. The number of oxygen adsorbed on the surface. The low resistance properties of the other CdO contribute to the easy transfer of electrons, in that method, a nickel-glycerol salt micro-ball is synthesized in a mixed solvent of glycerol and isopropanol by a solvent heat method, then the nickel-glycerol salt and the ferrous sulfate are mixed, and the Ni-Fe LDH material with high specific surface area is synthesized under the hydrothermal condition, and the LDH material has excellent performance Electrocatalytic water oxidation performance, in which, when Fe: Ni = 0.52: 1 (obtained by ICP test), the performance is optimal, and the current density is 10mA/ cm2 and the overpotential is only 344mV. the obtained material has a high specific surface area and a plurality of active sites on the surface, and the porous structure is beneficial to the transmission of electrons and materials, and the oxidation of the catalytic water It is more important to replace the Ni2 + in the Ni (OH) 2 to form the LDH structure, and the Fe has a higher binding energy. in that oxidation reaction of electrocatalytic wat, we think that the synthetic idea can be extended to other different composition and high The preparation method of the specific surface LDH material comprises the following steps of: firstly, synthesizing a 1, 3-propylene glycol cobalt precursor by a solvent thermal method, The surface area of the material is higher than 190m2/ g. The test of the photocatalytic water oxidation performance of the material under the 鈥減hotosensitizing agent-persulfate鈥

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