本文選題：光催化　切入點：鉍系化合物　出處：《合肥工業(yè)大學(xué)》2017年碩士論文

【摘要】：隨著人類社會的迅速發(fā)展,能源危機和環(huán)境污染問題日益嚴重。光催化技術(shù)被認為是解決這兩大問題最有效的途徑之一。在眾多的光催化材料中,TiO_2是被研究最多的一種。但是TiO_2的帶隙較寬,只能吸收太陽光中的紫外光部分,大大限制了其應(yīng)用。因此,開發(fā)新型具有可見光響應(yīng)的光催化劑十分重要,成為光催化研究領(lǐng)域的一大趨勢。鉍系化合物是一類重要的光催化劑,以其優(yōu)異的可見光光催化性能吸引了人們極大地研究興趣。本文以鉍系光催化劑為研究對象,通過不同合成途徑制備了三種不同的光催化劑,研究了其結(jié)構(gòu)、形貌及光催化性能,主要研究內(nèi)容如下:(1)利用水解法和后續(xù)的煅燒制備了一種具有高效可見光催化性能的β-Bi_2O_3納米粉體,通過XRD、SEM、HRTEM、XPS、UV-Vis等對其結(jié)構(gòu)和形貌進行表征,研究了不同退火溫度對產(chǎn)物形貌、結(jié)構(gòu)及光催化性能的影響。實驗結(jié)果表明,水解法直接得到的Bi_2O_3粉體的結(jié)晶性很低,當(dāng)煅燒溫度為300℃時,可以得到結(jié)晶性較好的β-Bi_2O_3納米粉體,其為薄納米片自組裝而成;繼續(xù)升高煅燒溫度,β-Bi_2O_3會轉(zhuǎn)變?yōu)楣獯呋阅茌^差的α-Bi_2O_3。300℃得到的β-Bi_2O_3在可見光照射下2 h內(nèi)對20 mg/L的甲基橙溶液的降解率為95%。(2)以乙二醇水溶液為溶劑,通過溶劑熱法合成了BiOI納米片;以BiOI納米片為基底,通過水浴法在硫代乙酰胺(TAA)溶液中成功制備了Bi_2S_3/BiOI復(fù)合光催化劑。通過改變TAA溶液的濃度,控制Bi_2S_3的負載量。當(dāng)TAA溶液的濃度為2mmol/L時,Bi_2S_3/BiOI復(fù)合體表現(xiàn)出最佳的光催化性能,可見光下在2 h內(nèi)對20mg/L的甲基橙溶液完全降解,性能相比較于單純的BiOI納米片有比較大的改善。光催化反應(yīng)機理研究表明復(fù)合體的特殊結(jié)構(gòu)有利于光生電子空穴的分離,降低了復(fù)合機率。(3)利用噴霧干燥法和后續(xù)煅燒制備了一種中空Bi_4Ti_3O_(12)微米球,通過DTA、XRD、SEM、UV-Vis等方法對樣品的結(jié)構(gòu)和形貌進行表征,優(yōu)化最佳制備工藝。結(jié)果表明當(dāng)煅燒溫度為600℃時,可以得到結(jié)晶性高、形貌均勻的中空狀Bi_4Ti_3O_(12)微米球。分別對樣品進行了紫外光和可見光的光催化性能試驗,結(jié)果表明Bi_4Ti_3O_(12)微米球只在紫外光下具備高效的光催化性能,并且當(dāng)溫度為600℃時光催化性能最佳。
[Abstract]:With the rapid development of human society, energy crisis and environmental pollution are becoming more and more serious.Photocatalytic technology is considered to be one of the most effective ways to solve these two problems.Among the many photocatalytic materials, TiOS _ 2 is the most studied.However, the band gap of TiO_2 is wide and can only absorb ultraviolet light from the sun, which greatly limits its application.Therefore, the development of new photocatalysts with visible light response is very important and has become a major trend in the field of photocatalysis.Bismuth compounds are a kind of important photocatalysts, which attract much attention because of their excellent visible photocatalytic properties.In this paper, three kinds of bismuth photocatalysts were prepared by different synthesis methods, and their structure, morphology and photocatalytic properties were studied.Effects of structure and photocatalytic properties.The experimental results show that the crystallization of Bi_2O_3 powders obtained by hydrolysis method is very low. When calcination temperature is 300 鈩，

本文編號：1726024