本文選題：納米氧化鋅 + 石墨烯　； 參考：《大連理工大學(xué)》2015年碩士論文

【摘要】：納米氧化鋅(ZnO)由于其獨(dú)特的性能,在光催化和太陽能電池領(lǐng)域應(yīng)用前景廣闊。但是,較低的量子產(chǎn)率和光能利用率使納米ZnO的光催化活性不高,這限制了其高效的應(yīng)用。此外,無法高效低能分離回收光催化后的ZnO,也是一個(gè)亟需解決的問題。針對(duì)上述兩種問題,本論文利用石墨烯修飾改性納米ZnO薄膜,并提出以玻璃基片為固定納米ZnO的載體,得到固化的有序多孔ZnO薄膜及其復(fù)合膜,對(duì)其光學(xué)性能、光催化活性及使用壽命進(jìn)行研究。以玻璃基片為固定載體,本研究通過浸漬提拉法制備了納米ZnO薄膜,解決了納米ZnO易流失、不易回收的問題。用掃描電鏡(SEM)、X衍射射線(XRD)等手段對(duì)薄膜進(jìn)行表征,考察其光學(xué)性能和光催化活性。結(jié)果表明,納米ZnO平鋪在玻璃基板上,晶型為六方纖鋅礦結(jié)構(gòu),尺寸為13.6nm；在500W汞燈下,60min納米ZnO薄膜光催化降解水溶液中亞甲基藍(lán)(MB)和甲基橙(MO)的效率分別為87.3%和54.2%；另外,隨甲基橙溶液濃度的增大,ZnO薄膜對(duì)甲基橙的降解率呈先增大后減小的趨勢(shì),當(dāng)濃度為3mg/L時(shí),甲基橙的降解率達(dá)到最大(92.8%)；使用壽命測(cè)試表明,90min回收的納米ZnO薄膜對(duì)甲基橙降解率在70%以上,光催化效果良好。為提高納米ZnO薄膜的光催化活性,以聚苯乙烯(Polystyrene)為模板,通過浸漬提拉法得到有序多孔ZnO薄膜,考察該薄膜光學(xué)性能及光催化活性。與納米ZnO薄膜相比,多孔ZnO薄膜的多孔結(jié)構(gòu)增大了膜的比表面積,并加快甲基橙在材料內(nèi)部傳遞,反應(yīng)活性位增多使催化活性增高；也增強(qiáng)了光吸收強(qiáng)度。500W汞燈下、90mmin有序多孔ZnO薄膜對(duì)甲基橙的降解率為94.7%,較納米ZnO薄膜80.2%的降解率有所提高。為進(jìn)一步提高納米ZnO薄膜的光催化活性,利用石墨烯改性納米ZnO薄膜,制備了ZnO-石墨烯復(fù)合膜和有序多孔ZnO-石墨烯復(fù)合膜,用XRD等手段對(duì)復(fù)合膜進(jìn)行表征,考察復(fù)合膜的光學(xué)性能、光催化活性和使用壽命。石墨烯的引入使ZnO光吸收強(qiáng)度上升,并且將光譜響應(yīng)范圍拓展到可見光區(qū),對(duì)ZnO晶型的六方纖鋅礦結(jié)構(gòu)未產(chǎn)生影響；在500W汞燈下,90mmin內(nèi)石墨烯修飾的ZnO有序多孔復(fù)合膜降解甲基橙的效率最高(99.7%),致密復(fù)合膜次之(93.5%),納米ZnO薄膜最低(80.2%)：此外,隨氧化石墨烯溶膠濃度的增加,由于石墨烯負(fù)載量不同,ZnO-石墨烯復(fù)合膜對(duì)甲基橙的降解率呈先增大后減小的趨勢(shì)。使用壽命測(cè)試表明,90min內(nèi)回收的ZnO-石墨烯復(fù)合膜降解甲基橙的效率均在90%以上,優(yōu)于ZnO薄膜70%的效率,光催化活性良好。
[Abstract]:Nanocrystalline zinc oxide (ZnO) is widely used in photocatalysis and solar cells due to its unique properties.However, the low quantum yield and utilization efficiency of light energy make the photocatalytic activity of nanometer ZnO low, which limits its high efficiency.In addition, it is an urgent problem that ZnO can not be separated efficiently and low energy after photocatalytic recovery.In order to solve the above two problems, in this paper, graphene was used to modify the nano-scale ZnO film, and the glass substrate was used as the carrier to immobilize the nanometer ZnO. The ordered porous ZnO film and its composite film were obtained, and the optical properties of the film were analyzed.The photocatalytic activity and service life were studied.Nanocrystalline ZnO thin films were prepared by dipping Czochralski method with glass substrate as the stationary carrier. The problem of easy loss of nanometer ZnO and difficult recovery was solved.The thin films were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD), and their optical properties and photocatalytic activity were investigated.The results showed that the nanocrystalline ZnO was coated on glass substrates with hexagonal wurtzite structure with a size of 13.6 nm, and the photocatalytic degradation efficiency of methylene blue blue MBb and methyl orange molybdenum in aqueous solution was 87.3% and 54.2%, respectively, under 500W Hg lamp for 60min.With the increase of the concentration of methyl orange solution, the degradation rate of methyl orange film increased first and then decreased. When the concentration was 3mg/L,The degradation rate of methyl orange was up to 92.8%, and the test of service life showed that the degradation rate of methyl orange was more than 70% and the photocatalytic effect was good.In order to improve the photocatalytic activity of nano-sized ZnO films, the ordered porous ZnO thin films were prepared by dipping Czochralski method using polystyrene polystyrene as template. The optical properties and photocatalytic activity of the films were investigated.Compared with nanometer ZnO thin films, porous ZnO films increase the specific surface area of the films, accelerate the transfer of methyl orange in the materials, and increase the catalytic activity due to the increase of reactive sites.The degradation rate of methyl orange by 90 mmin ordered porous ZnO film was 94.7%, which was higher than that of nano-sized ZnO film (80.2%).In order to further improve the photocatalytic activity of nanometer ZnO films, ZnO-graphene composite films and ordered porous ZnO-graphene composite films were prepared by using graphene modified nano- films. The composite films were characterized by XRD.The optical properties, photocatalytic activity and service life of the composite films were investigated.With the introduction of graphene, the light absorption intensity of ZnO is increased, and the spectral response range is extended to the visible region, which has no effect on the hexagonal wurtzite structure of ZnO crystal.Under a 500W mercury lamp, the highest degradation efficiency of methyl orange was obtained by graphene modified ZnO ordered porous composite membrane within 90mmin, followed by dense composite film (93.5A), and nanometer-sized ZnO film (80.2cm). In addition, with the increase of graphene oxide sol concentration,The degradation rate of methyl orange by ZnO- graphene composite film increased firstly and then decreased due to the different loading amount of graphene.The test of service life showed that the efficiency of degradation of methyl orange by ZnO-graphene composite membrane recovered within 90 minutes was above 90%, which was superior to that of ZnO film by 70%, and the photocatalytic activity was good.
【學(xué)位授予單位】：大連理工大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2015
【分類號(hào)】：TQ132.41;TB33

【共引文獻(xiàn)】

相關(guān)期刊論文 前10條

1 龍亞平;曾葆青;楊云;柳建龍;吳U，

本文編號(hào)：1767313