本文選題：ZnO + 復合物��； 參考：《濟南大學》2017年碩士論文

【摘要】：本論文采用水熱及溶劑熱法,利用不同的表面活性劑控制合成了不同形貌的Zn O微納米材料,主要包括納米棒、蝴蝶花、介晶微球等,探究了不同微結構的形成機理。在此基礎上,本文進一步研究了在不引入外加還原劑的條件下,通過簡單攪拌和超聲化學法制備了ZnO/Au復合物,并探索了上述條件下Au3+還原為Au0的機理。對于合成的ZnO及ZnO/Au復合結構進行了光催化降解有機染料的性能研究,并討論了其光催化機理。此外,基于金屬有機框架結構(MOF)的廣泛應用,本文以此為前驅體制備了分級ZnO/NiO復合材料并研究其超級電容器的性能。本文的具體研究內容如下:1.蝴蝶狀ZnO微納結構的制備以及利用其自還原能力合成ZnO/Au復合物,該復合物表現出增強的光催化活性。以酒石酸作為表面活性劑,采用水熱法和后續(xù)的煅燒過程,制備得到形貌各異的ZnO微納米結構,特別是形貌新穎的蝴蝶狀ZnO結構。蝴蝶狀ZnO結構的形成機理解釋為:在納米顆粒與重建納米片之間靜電相互作用的誘導下,晶體的成核-生長-自組裝過程。在蝴蝶狀Zn O表面沉積Au納米顆粒的過程中沒有引入外加還原劑,僅僅通過室溫攪拌含有HAuCl4·4H2O的ZnO溶液即可獲得ZnO/Au復合物。研究表明:低溫煅燒制備ZnO的過程中,ZnO表面的酒石酸分子結晶成為晶體,使得所得樣品對Au3+表現出還原性。光催化研究結果顯示:ZnO-Au復合物比純的ZnO樣品具有明顯增強的光催化活性。2.采用超聲化學法在ZnO納米棒表面原位生長Au納米顆粒,所得復合物表現出優(yōu)異的光催化能力。超聲體系中不添加任何外加還原劑,在ZnO納米棒表面實現Au的原位沉積,主要原因是:在超聲處理過程中,體系中會產生具有還原性的H原子和自由電子。所得的Au/ZnO異質結在光催化降解過程中表現出優(yōu)異的光催化活性。特別地,當Au的理論負載量達到4%時,Au/ZnO復合物可以在12 min內完全降解RhB染料。光催化活性增強的原因是復合物中Au可以作為電子捕獲劑,加強光生電子-空穴的分離。上述Au/ZnO復合物可以循環(huán)應用5次而沒有明顯的活性衰弱,表明該催化劑具有較好的循環(huán)穩(wěn)定性。此外,CO氧化的研究結果表明:Au的引入極大地增強了ZnO材料的催化活性,主要原因是復合物中Au納米顆粒可以為催化CO過程提供更多的反應活性位點。3.納米片基線團狀ZnO微球的制備及光催化應用研究。以酒石酸作為結構導向劑,采用水熱法合成了由ZnO納米片組裝而成的線團狀Zn O介晶。實驗研究表明六亞甲基四胺(HMT)的濃度對ZnO產物的尺寸分布及納米片的堆疊程度起到非常重要的影響。結合系統(tǒng)時間依賴實驗的結果,可以推測納米片基ZnO介晶的形成原因可能是納米片間偶極相互作用和預形成內核產生的電場作用的協(xié)同效應。在不同HMT濃度下制備所得樣品的光催化研究結果表明:產物的暗處理吸附能力和光降解能力隨HMT濃度的增加而增強,可能的原因是ZnO樣品比表面積的增加促進了光生載流子在催化劑和染料分子之間的遷移。4.MOF驅動合成分級ZnO/NiO微結構及超級電容器性質研究。以對苯二甲酸作為有機連接劑,采用溶劑熱法和隨后N2/O2氣氛下的煅燒過程合成納米片基分級ZnO/NiO微米結構。實驗探究表明:Zn~(2+)與Ni~(2+)的摩爾比對產物的微觀結構和超級電容器性能均有重要的影響。特別地,當Zn~(2+)和Ni~(2+)的摩爾比分別控制為1:2和1:1時,我們可以分別獲得由納米片組裝而成的分級ZnO/NiO中空微球和微米花。當樣品用作超級電容器的電極時,相比于中空微球,花狀ZnO/NiO表現出更大的比電容和更高的比容量。在電流密度為1 A g-1時,所得微米花的比電容可以達到435.1 F g-1。該微米花狀復合物表現出優(yōu)異的電化學性能主要是因為該微結構為具有更小的本征電阻和電荷遷移阻抗。
[Abstract]:This paper adopts the hydrothermal and solvothermal method by controlling the different morphologies of Zn synthesis of O micro nano materials of different surfactants, including nanorods, butterfly, mesomorphous microspheres, explores different microstructure formation mechanism. On this basis, this paper further studies without introducing external reducing agent under the condition, through simple stirring and ultrasonic chemical preparation of ZnO/Au composites, and explores the conditions for reducing Au3+ Au0 and ZnO/Au ZnO. The mechanism for the synthesis of composite structure is studied the performance of photocatalytic degradation of organic dye, the photocatalytic mechanism was discussed. In addition, metal organic frameworks (based on MOF) has been widely used, based on the performance of a precursor for the preparation of graded ZnO/NiO composites and study the supercapacitor. The specific contents of this paper are as follows: 1. butterfly shaped ZnO micro nano structure and preparation Use the reduction ability of synthesis of ZnO/Au complexes, the complexes exhibited enhanced photocatalytic activity. Using tartaric acid as surfactant by hydrothermal method and subsequent calcination process, prepared with various morphologies ZnO micro nano structure, especially the structure and morphology of butterfly shaped ZnO novel butterfly shaped ZnO structure. The formation mechanism is explained as follows: in between nanoparticles and nano film induced reconstruction of electrostatic interactions, crystal nucleation and growth and self-assembly process. Without introducing external reducing agent in the process of butterfly shaped Zn O Au surface deposition of nanoparticles, only by stirring at room temperature, ZnO solution containing HAuCl4 to 4H2O ZnO/Au complex was obtained. The results show that: the low temperature calcination process of preparing ZnO, tartaric acid molecules on the surface of ZnO crystal as crystal, the samples showed a reduction of Au3+. The photocatalytic results show that the ZnO-Au composite With the photocatalytic activity of.2. was significantly enhanced by ultrasonic chemical method of Au nanoparticles in the in situ growth of ZnO nanorods than pure ZnO samples, the composites show excellent photocatalytic ability. The ultrasonic system does not add any external reducing agent, in situ deposition of Au ZnO nanorods, the main reason is: the ultrasonic treatment process, system will produce a reduction of H atoms and free electrons. The Au/ZnO heterojunction exhibited excellent photocatalytic activity in photocatalytic degradation process. Especially, when the theory of Au load reached 4%, Au/ZnO complexes can be completely degraded within 12 min RhB dye. The enhanced photocatalytic activity of compound Au can be used as electron capture agent, strengthen the separation of photoinduced electron hole. The Au/ZnO complex can be recycled 5 times without application of activity weakened obviously, show that the The catalyst has good cycle stability. In addition, the research of CO oxidation results show that the addition of Au greatly enhanced the catalytic activity of ZnO materials, the main reason is the preparation and photocatalytic application of Au nano particle composites can provide more reactive sites of nano.3. baseline ball like ZnO microspheres as catalyst for CO process. Using tartaric acid as a structure directing agent were synthesized by hydrothermal method by ZnO nanosheets assembled Zn O coil like mesomorphous. Experimental research shows that six of four methylene amine (HMT) concentration on ZnO product size distribution and nano sheet stack level play a very important influence binding. Time dependent experimental results, the formation of reasons to suspect that ZnO nanosheet based dielectric crystal may be a synergistic effect between Nano dipole interaction and pre forming electric field generated by the kernel. Prepared under different HMT concentrations The results of photocatalytic samples show that the product of the dark adsorption ability and photocatalytic ability increases with the increase of HMT concentration, the possible reason is that ZnO promotes the migration of.4.MOF samples of photogenerated carriers between catalyst and dye molecules driven synthesis of hierarchical ZnO/NiO microstructures and properties of super capacitor on the increase of specific surface area. Using terephthalic acid as organic linkers by solvothermal method and then N2/O2 atmosphere calcination process of synthesis of nano film grade ZnO/NiO micron structure. The experimental research shows: Zn~ (2+) and Ni~ (2+) have an important effect on the microstructure of the molar ratio of products and super capacitor properties were. Especially, when Zn~ (2+) and Ni~ (2+) molar ratio respectively control for 1:2 and 1:1, we can respectively obtain assembled by nanoplates grade ZnO/NiO hollow microspheres and microflowers. As the sample with super capacitor The electrode, compared with hollow microspheres, flower like ZnO/NiO showed greater capacitance and higher capacity. At a current density of 1 A g-1, the microflowers capacitance can reach 435.1 F g-1. the micron flower complexes exhibit excellent electrochemical performance is mainly due to the micro structure has smaller intrinsic resistance and charge transfer impedance.

【學位授予單位】：濟南大學
【學位級別】：碩士
【學位授予年份】：2017
【分類號】：TB33;TM53

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本文編號：1746772