本文選題：二維負(fù)載型多組分催化劑 + Bi_2S_3/BiOCl��； 參考：《華東師范大學(xué)》2017年碩士論文

【摘要】：隨著科技的進(jìn)步,工業(yè)生產(chǎn)加速所帶來的環(huán)境問題也日益受到社會(huì)的廣泛關(guān)注。其中,工業(yè)排放的廢水中因含有大量毒性強(qiáng)、穩(wěn)定性高、難生物降解的有害物質(zhì),已經(jīng)給生物體健康和環(huán)境保護(hù)帶來了巨大危害。由于半導(dǎo)體光催化氧化技術(shù)具有操作簡(jiǎn)單、反應(yīng)條件較容易實(shí)現(xiàn)且不會(huì)對(duì)環(huán)境產(chǎn)生的二次污染等優(yōu)點(diǎn),因此其在環(huán)境保護(hù)方面取得了廣泛的關(guān)注。而光催化技術(shù)作為利用光能有效凈化水污染的手段在環(huán)境方面有著巨大的發(fā)展空間,但目前它面臨對(duì)可見光吸收有限以及光生電子和空穴易復(fù)合等問題。大量實(shí)驗(yàn)表明,多組分的復(fù)合材料比單組分的具有較高的活性。主要原因有匹配的能帶結(jié)構(gòu)以及能抑制光生電子和空穴的再復(fù)合�；谝陨涎芯勘尘拔覀冞x擇對(duì)二維負(fù)載型納米復(fù)合光催化材料為研究對(duì)象,以提高光生電子-空穴分離為目標(biāo),開展了以下三方面的研究工作。一、利用甘露醇水熱合成含有大量氧缺陷的BiOCl納米片,再通過加入不同質(zhì)量的硫代乙酰胺(TAA),采用離子交換法制備出Bi_2S_3/BiOCl復(fù)合光催化劑。根據(jù)光催化實(shí)驗(yàn)結(jié)果可知,當(dāng)TAA加入的質(zhì)量比為28.8%時(shí),復(fù)合光催化劑顯示了最優(yōu)的光催化降解羅丹明B(RhB)的能力,分別是單一的BiOCl與Bi_2S_3的2.5和16倍。由捕獲劑實(shí)驗(yàn)可知,此體系的主要活性物種為02.和h+,但·OH也有一定的影響,因此我們通過查閱相關(guān)的文獻(xiàn)和基于所得的實(shí)驗(yàn)結(jié)果推測(cè)出Bi_2S_3/BiOCl反應(yīng)機(jī)理。二、首先利用尿素通過馬弗爐加熱煅燒得到淡黃色固體g-C_3N_4,碾磨均勻之后再放于馬弗爐再次煅燒得到剝片的g-C_3N_4,再采用沉淀法合成了g-C_3N_4/BiOCl復(fù)合物,隨后利用TAA合成了 Bi_2S_3/g-C_3N_4/BiOCl復(fù)合物。當(dāng)離子交換時(shí)間為0.5h時(shí),所得樣品的光催化效率最高,其光催化反應(yīng)速率分別是單一的BiOCl與g-C_3N_4的2和13倍。由于g-C_3N_4與BiOCl能帶隙結(jié)構(gòu)匹配,再加上利用簡(jiǎn)單的離子交換法在BiOCl表面生成Bi_2S_3,大大提高了界面電荷的有效轉(zhuǎn)移。捕獲劑實(shí)驗(yàn)說明O_2·和h+為光催化過程中的活性物種,而·OH則不存在。查閱相關(guān)文獻(xiàn)和基于所得的實(shí)驗(yàn)結(jié)果我們推測(cè)出Bi_2S_3/g-C_3N_4/BiOCl反應(yīng)機(jī)理。三、首先利用HF水熱合成片狀的TiO_2,再通過利用片狀的TiO_2作為結(jié)構(gòu)誘導(dǎo)劑,在低溫下一步合成二維TiO_2/ZnIIn2S4復(fù)合物。通過可見光光催化降解RhB探究出兩者的最優(yōu)配比為TiO_2/ZnIn2S =1/1,是單獨(dú)ZnIn2S4反應(yīng)速率的3.8倍。ZnIn2S4的負(fù)載導(dǎo)致TiO_2對(duì)可見光有吸收作用,另一方面也抑制ZnIn2S4光生電子和空穴的復(fù)合。
[Abstract]:With the development of science and technology, the environmental problems caused by the acceleration of industrial production are paid more and more attention by the society. Among them, industrial wastewater contains a large number of toxic, high stability, difficult to biodegradable harmful substances, has brought great harm to the health of organisms and environmental protection. Due to the advantages of semiconductor photocatalytic oxidation technology, such as simple operation, easy implementation of reaction conditions and no secondary pollution to the environment, the semiconductor photocatalytic oxidation technology has been widely concerned in the field of environmental protection. However, photocatalytic technology, as a means of effectively purifying water pollution by using light energy, has a great space for development in the field of environment, but at present it is faced with the problems of limited absorption of visible light and easy recombination of photogenerated electrons and holes. A large number of experiments show that the multicomponent composite has higher activity than that of single component. The main reasons are matching band structure and recombination of photogenerated electrons and holes. Based on the above research background, we selected the two-dimensional supported nano-composite photocatalytic materials as the research object, with the aim of improving photogenerated electron-hole separation, we carried out the following three aspects of research work. Firstly, BiOCl nanoparticles with large oxygen defects were synthesized by hydrothermal synthesis of mannitol, and then Bi_2S_3/BiOCl composite photocatalysts were prepared by ion exchange method by adding different quality thioacetamide (TAA). According to the results of photocatalytic experiments, when the mass ratio of TAA was 28.8wt%, the composite photocatalyst showed the best photocatalytic degradation ability of Rhodamine Bhh B, which was 2.5 and 16 times of that of single BiOCl and Bi_2S_3, respectively. The main active species of this system are 0 2. And h, but OH also has some influence, so we infer the mechanism of Bi_2S_3/BiOCl reaction based on the related literature and experimental results. Secondly, the yellowish solid g-C _ 3N _ 4 was obtained by heating and calcining with urea in muffle furnace to obtain g-C _ 3N _ 4, then the g-C _ 3N _ 3N _ 4 was calcined in a muffle furnace, then the g-C_3N_4/BiOCl complex was synthesized by precipitation method, and then the Bi_2S_3/g-C_3N_4/BiOCl complex was synthesized by TAA. When the ion exchange time is 0.5 h, the photocatalytic efficiency of the obtained sample is the highest, and the photocatalytic reaction rate is 2 and 13 times of that of the single BiOCl and g-C_3N_4, respectively. Because of the matching of the energy band gap structure between g-C_3N_4 and BiOCl, and by using the simple ion exchange method to generate Bi2S _ 3 on the surface of BiOCl, the effective transfer of interfacial charge is greatly improved. The trapping agent experiments show that O _ 2 and h are active species in photocatalytic process, but OH does not exist. We infer the mechanism of Bi_2S_3/g-C_3N_4/BiOCl reaction by consulting relevant literature and experimental results. Thirdly, firstly, TiO-2 was synthesized by hydrothermalization of HF, and then two-dimensional TiO_2/ZnIIn2S4 complex was synthesized at low temperature by using flake TiO_2 as structure inducer. It was found that the optimum ratio of TiO_2/ZnIn2S and ZnIn2S4 for the degradation of RhB by visible light was 1 / 1, which was 3.8 times of the rate of ZnIn2S4 reaction. The loading of ZnIn2S4 led to the absorption of visible light by TiO_2, on the other hand, it also inhibited the combination of photogenerated electrons and holes in ZnIn2S4.
【學(xué)位授予單位】：華東師范大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類號(hào)】：O643.36

【參考文獻(xiàn)】

中國期刊全文數(shù)據(jù)庫 前3條

1 宋改雪;儲(chǔ)震宇;金萬勤;孫紅旗;;可見光催化降解有機(jī)污染物g-C_3N_4/TiO_2光催化劑的性能增強(qiáng)（英文）[J];Chinese Journal of Chemical Engineering;2015年08期

2 韓世同,習(xí)海玲,史瑞雪,付賢智,王緒緒;半導(dǎo)體光催化研究進(jìn)展與展望[J];化學(xué)物理學(xué)報(bào);2003年05期

3 范少華,崔玉民;光催化技術(shù)在污水處理方面的應(yīng)用[J];化工進(jìn)展;2002年05期

，

本文編號(hào)：1825744