本文選題：激光熔融法 + 金屬氧化物　； 參考：《中國地質(zhì)大學(xué)(北京)》2017年碩士論文

【摘要】：金屬氧化物具有較為廣泛的應(yīng)用,如光催化、生物醫(yī)藥和太陽能電池等領(lǐng)域。文獻(xiàn)中,傳統(tǒng)的改性方法有元素?fù)诫s、形貌調(diào)控等。但元素?fù)诫s會在材料中引入雜質(zhì),而自摻雜的方法可以有效解決該問題。本論文采用缺陷自摻雜的方法對材料進(jìn)行改性。本論文采用激光熔融法,制備得到了缺陷型TiO_2、Fe_3O_4和SrTiO_3,并對其進(jìn)行系統(tǒng)表征。研究發(fā)現(xiàn):(1)激光熔融處理后得到的TiO_2樣品中出現(xiàn)了Ti_8O_(15)相,且其禁帶寬度由3.03 eV降低到2.52 eV,表明激光熔融法成功在TiO_2中引入了氧缺陷和Ti~(3+),能增強(qiáng)其對可見光的吸收能力。具有缺陷的TiO_2不僅具有優(yōu)異的光催化降解有機(jī)物和光催化制氫性能,還具有良好的穩(wěn)定性。TiO_2激光熔融后的產(chǎn)氫率為8.54mmol/(h·g),約為市售TiO_2(P25)樣品的8倍。(2)利用激光熔融法處理Fe_2O_3和Fe_3O_4,均最終獲得了Fe_3O_4。激光熔融法使Fe_2O_3轉(zhuǎn)變成Fe_3O_4,表明激光熔融法成功在Fe_3O_4中引入了缺陷。具有缺陷的Fe_3O_4是一種超順磁性材料,其飽和磁化強(qiáng)度高,而矯頑力和剩磁分別是6.6Oe和0.4 emu/g(近似為零)。此外,由于磁晶各向異性對溫度敏感,所以激光熔融處理后Fe_3O_4樣品在低溫下飽和磁化強(qiáng)度略有增強(qiáng)。(3)激光熔融處理后得到的SrTiO_3樣品的相組成沒有變化,但是根據(jù)其禁帶寬度從3.20 eV降低到3.05 eV,表明激光熔融法成功在SrTiO_3中引入了缺陷,從而增強(qiáng)SrTiO_3對可見光的吸收能力。具有缺陷的SrTiO_3的光催化制氫性能有所提高,且具有良好的循環(huán)穩(wěn)定性。SrTiO_3激光熔融后的產(chǎn)氫率為2.46μmol/(h·g),約為原始樣品的3.5倍。
[Abstract]:Metal oxides have a wide range of applications, such as photocatalysis, biopharmaceutical and solar cells. In the literature, the traditional modification methods include element doping, morphology regulation and so on. However, impurity doping can be introduced into the material, and the self doping method can effectively solve the problem. The defect type TiO_2, Fe_3O_4 and SrTiO_3 were prepared and characterized by laser melting method. The study showed that: (1) the Ti_8O_ (15) phase appeared in the TiO_2 samples obtained after laser melting, and the band gap was reduced from 3.03 eV to 2.52 eV, indicating that the laser melting method successfully introduced oxygen in TiO_2. Defects and Ti~ (3+) can enhance their absorptive capacity to visible light. The defective TiO_2 not only has excellent photocatalytic degradation of organic matter and photocatalytic hydrogen production, but also has good stability after.TiO_2 laser melting, the hydrogen production rate is 8.54mmol/ (H. G), about 8 times that of commercial TiO_2 (P25) samples. (2) treatment of Fe_2O_3 by laser melting method. And Fe_3O_4, the Fe_3O_4. laser melting method finally obtained the transformation of Fe_2O_3 into Fe_3O_4, which indicates that the laser melting method successfully introduced the defect in Fe_3O_4. The defective Fe_3O_4 is a superparamagnetic material with high saturation magnetization, while the coercive force and the remanence are 6.6Oe and 0.4 emu/g (approximately zero), respectively. In addition, magnetocrystalline anisotropy The opposite sex is sensitive to temperature, so the saturation magnetization of Fe_3O_4 samples at low temperature is slightly enhanced after laser melting. (3) the phase composition of SrTiO_3 samples obtained after laser melting is not changed, but the band gap is reduced from 3.20 eV to 3.05 eV, indicating that laser melting method has successfully introduced defects in SrTiO_3 and thus enhanced S. RTiO_3 absorbs the visible light. The photocatalytic hydrogen production performance of the defective SrTiO_3 has improved, and has good cyclic stability. The hydrogen production rate after.SrTiO_3 laser melting is 2.46 mol/ (H. G), which is about 3.5 times that of the original sample.

【學(xué)位授予單位】：中國地質(zhì)大學(xué)(北京)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2017
【分類號】：TQ123.4
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本文編號：1779066