發(fā)布時(shí)間：2018-06-08 19:25

  本文選題：鎢酸鉍 + 半導(dǎo)體��； 參考：《天津科技大學(xué)》2017年碩士論文

【摘要】：近年來(lái),由于在治理環(huán)境污染和光解水制氫方面表現(xiàn)出潛在的應(yīng)用前景,光催化技術(shù)得到了研究者的廣泛關(guān)注。紫外光響應(yīng)光催化劑如Ti02禁帶寬度約為3.2ev,僅吸收占太陽(yáng)光4%的紫外光(λ400nm)部分,嚴(yán)重限制了太陽(yáng)能的利用,而太陽(yáng)光中的可見(jiàn)光部分占太陽(yáng)光能量的45%,因此,可見(jiàn)光響應(yīng)光催化劑成為當(dāng)前研究的熱點(diǎn)和重點(diǎn)。其中,鎢酸鉍(Bi2W06)的禁帶寬度約為2.7ev,是潛在的可見(jiàn)光響應(yīng)光催化劑。本文采用溶膠凝膠法制備可見(jiàn)光催化劑Bi2W06,并利用X射線(xiàn)衍射、掃描電鏡、紅外光譜和紫外可見(jiàn)分光光度計(jì)等技術(shù)手段表征樣品的結(jié)構(gòu)和性能。以紫外光為光源,甲基橙為降解對(duì)象,考察了催化劑焙燒溫度、甲基橙溶液pH、甲基橙濃度、催化劑用量對(duì)催化體系的影響。并以氙燈模擬太陽(yáng)光,考察了兩種光源在體系中的光催化活性。光催化降解實(shí)驗(yàn)表明,甲基橙溶液pH=3,催化劑用量為1.2g/L,甲基橙溶液濃度為5mg/L時(shí),使用400℃焙燒的Bi2W06,有最好的光催化活性。1.2g/L、400℃焙燒的Bi2W06粉末,降解10mg/L、pH=3的甲基橙溶液,氙燈光照150min降解率達(dá)到92%,太陽(yáng)光降解率達(dá)到了 58%。采用無(wú)模板水熱法,通過(guò)HNO3和NH3·H20調(diào)節(jié)體系的pH值,合成不同形貌和光催化活性的Bi2W06粉體催化劑。并利用X射線(xiàn)衍射、透射電鏡、紅外光譜、紫外可見(jiàn)分光光度計(jì)、紫外可見(jiàn)漫反射光譜和N2吸附脫附法等技術(shù)手段表征樣品的結(jié)構(gòu)和性能。光催化降解實(shí)驗(yàn)表明,在pH=7時(shí),反應(yīng)溫度為180℃,反應(yīng)時(shí)間為24h,合成了納米尺寸的Bi2W06樣品,且具有最佳的光催化活性,降解10mg/L的羅丹明B溶液,350w氙燈光照60min降解率達(dá)到了 95.6%。
[Abstract]:In recent years, photocatalytic technology has attracted wide attention due to its potential application in environmental pollution control and hydrogen production by photolysis water. The ultraviolet photocatalyst, such as Ti02 photocatalyst, has a band gap of 3.2evand absorbs only 4% of the solar light (位 400nm), which seriously limits the utilization of solar energy, while the visible light in the solar light accounts for 45% of the solar energy. Visible light-responsive photocatalyst has become the focus and focus of current research. The band gap of bismuth tungstate Bi2W06) is about 2.7 ev. it is a potential visible light responsive photocatalyst. In this paper, the visible light catalyst Bi2W06was prepared by sol-gel method. The structure and properties of the samples were characterized by X-ray diffraction, scanning electron microscopy, infrared spectroscopy and UV-Vis spectrophotometer. The effects of calcination temperature, pH of methyl orange solution, concentration of methyl orange and the amount of catalyst on the catalytic system were investigated with ultraviolet light as light source and methyl orange as degradation object. The photocatalytic activity of the two light sources in the system was investigated by using xenon lamp to simulate solar light. The photocatalytic degradation experiment showed that the best photocatalytic activity of Bi2W06 calcined at 400 鈩，

本文編號(hào)：1996921