本文選題：光催化 + 非金屬摻雜�。� 參考：《中國科學(xué)院大學(xué)(中國科學(xué)院物理研究所)》2017年碩士論文

【摘要】：揭示光催化劑中的電子態(tài)的結(jié)構(gòu)對于深刻理解光催化反應(yīng)過程至關(guān)重要。與此同時,電子態(tài)結(jié)構(gòu)的改變又和半導(dǎo)體帶隙中的缺陷態(tài)(局域態(tài))密切相關(guān)。本論文從材料中缺陷態(tài)所產(chǎn)生的光生載流子為出發(fā)點,采用時間分辨紅外光譜技術(shù)手段,研究了非金屬摻雜氧化鈦光催化材料的一些基本物理化學(xué)性質(zhì)。其中主要有以下兩方面的工作:(1)利用瞬態(tài)紅外吸收-激發(fā)掃描光譜技術(shù)對非金屬硼摻雜的氧化鈦進行了研究。實驗發(fā)現(xiàn),對核心含硼的氧化鈦樣品進行光解水實驗,其產(chǎn)氫性能良好,而產(chǎn)氧效果不佳。當(dāng)我們通過加熱的手段將核心的硼移動到氧化鈦表面后,其光解水產(chǎn)氧的效果優(yōu)于核心含硼的樣品,但是其產(chǎn)氫的性能大打折扣,不如前者。從紅外光譜表征的結(jié)果看,是因為核心含硼的樣品其價帶上方含有大量的深束縛能級,這些能級的存在束縛了光生空穴,使其氧化能力下降。而在表面含硼的樣品中其價帶上方的深束縛能級被清除,空穴的氧化能力得以保留,但是在表面含硼的樣品中表面的硼會成為光生電子的受體,阻止了電子與質(zhì)子的反應(yīng),導(dǎo)致了產(chǎn)氫效果不佳。(2)利用瞬態(tài)紅外吸收光譜對非金屬氮摻雜的氧化鈦樣品的光生載流子行為進行了初步研究。發(fā)現(xiàn)隨著摻氮濃度的增加,樣品吸收可見光的范圍和吸光系數(shù)會增加,但同時復(fù)合中心也隨之增加,因此加快了光生載流子的復(fù)合。在硼氮共摻的氧化鈦樣品(紅鈦)中,紅鈦成功實現(xiàn)了可見光的吸收,即使在525nm光激發(fā)情況下仍有大量的光生載流子生成并伴有長時間壽命。在此光照條件下,未摻雜的氧化鈦及單一摻雜的氧化鈦(單純硼摻雜或氮摻雜)樣品產(chǎn)生的光生載流子的數(shù)量都沒有紅鈦產(chǎn)生的量多,而且壽命也沒有紅鈦長。
[Abstract]:It is important to reveal the structure of the electronic state in the photocatalyst for a deep understanding of the photocatalytic reaction process. At the same time, the change of electronic state structure is closely related to the defect state (local state) in the semiconductor band gap. In this paper, the basic physical and chemical properties of nonmetallic doped titanium oxide photocatalytic materials are studied by time-resolved infrared spectroscopy (TRS), starting from the photogenerated carriers produced by defective states in the materials. Among them, there are two main aspects: 1) the nonmetallic boron doped titanium oxide has been studied by transient infrared absorption-excitation scanning spectroscopy. It was found that the hydrogen production of titanium oxide samples containing boron was good, but the effect of oxygen production was not good. When the core boron is moved to the surface of titanium oxide by heating, the effect of photodissociation of aquatic oxygen is better than that of the core sample containing boron, but its hydrogen production is not as good as the former. The results of IR spectra show that there are a large number of deep bound energy levels above the valence band of the core samples containing boron. The existence of these energy levels binds the photogenerated holes and decreases the oxidation ability of the samples. The deep bound energy level above the valence band in the sample containing boron on the surface is removed, and the oxidation ability of the hole is preserved. However, the boron on the surface of the sample containing boron on the surface becomes the receptor of photogenerated electrons, which prevents the reaction between the electron and the proton. The photo-carrier behavior of non-metallic nitrogen-doped titanium oxide samples was studied by transient infrared absorption spectroscopy. It is found that with the increase of nitrogen concentration, the range of visible light absorption and the absorption coefficient will increase, but at the same time, the recombination center will also increase, which accelerates the recombination of photogenerated carriers. In the boron nitrogen co-doped titanium oxide (red titanium) samples, the visible light absorption of the red titanium was successfully realized. Even under the 525nm light excitation, a large number of photogenerated carriers were formed with long lifetime. Under these illumination conditions, the number of photogenerated carriers produced by undoped titanium oxide and single doped titanium oxide (pure boron doped or nitrogen doped) samples is not as large as that of red titanium, and the lifetime is not as long as that of red titanium.
【學(xué)位授予單位】：中國科學(xué)院大學(xué)(中國科學(xué)院物理研究所)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2017
【分類號】：O643.36;O644.1
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本文編號：1938096