论文总字数：19897字

摘 要

提高光催化剂对可见光的利用率是目前光催化领域研究的热点。Bi₂O₂CO₃光催化剂由于其特殊的层状结构，引起广大研究人员的关注。但由于Bi₂O₂CO₃的带隙较宽（3.1-3.5eV）,使其仅在紫外光（小于5％的太阳光）下是有效的，限制了其实际应用。因此需要对Bi₂O₂CO₃进行改性，实现其在光催化领域的应用价值。

首先，以Bi（NO₃）₃·5H₂O，柠檬酸钠，脲素为原料，聚乙烯吡咯烷酮（PVP）为分散剂，通过水热法制备Bi₂O₂CO₃微球；然后将Ag/AgCl负载到Bi₂O₂CO₃微球上，得到复合材料Ag/AgCl/Bi₂O₂CO₃；同时以AgNO₃和KCl为原料制备Ag/AgCl。通过X射线衍射，傅里叶变换红外光谱，扫描电子显微镜对所制备的样品（Bi₂O₂CO₃、Ag/AgCl/Bi₂O₂CO₃和Ag/AgCl）进行表征，结果表明，所制备的样品Bi₂O₂CO₃、Ag/AgCl/Bi₂O₂CO₃和Ag/AgCl已经成功得到。

在可见光照射下研究Bi₂O₂CO₃、Ag/AgCl/Bi₂O₂CO₃和Ag/AgCl分别对模拟有机污染物亚甲蓝（MB）的光催化活性，结果表明，在300W氙灯光照20min后，样品Bi₂O₂CO₃、Ag/AgCl/Bi₂O₂CO₃和Ag/AgCl降解亚甲蓝的效率分别为31.3％、99.3％、55％，所制备的Ag/AgCl/Bi₂O₂CO₃显示出较高的光催化活性；此外在可见光下研究Ag/AgCl/Bi₂O₂CO₃对模拟有机污染物甲基橙（MO）、罗丹明B（RhB）的光催化活性，结果表明Ag/AgCl/Bi₂O₂CO₃在20min内对甲基橙（MO）、罗丹明B（RhB）的降解基本完成，由此说明Ag/AgCl/Bi₂O₂CO₃复合材料具有优越的光催化活性。

关键词：Bi₂O₂CO₃ 可见光光催化剂 异质结 有机污染物

Preparation of Bi₂O₂CO₃ and Its Photocatalytic roperties

Abstract

The improvement of the utilization rate of visible light by photocatalyst is a hotspot in the field of photocatalysis. Because of its special layered structure, Bi₂O₂CO₃ photocatalysts have attracted the attention of researchers. However, due to the wide band gap of Bi₂O₂CO₃ (3.1-3.5eV), it is only effective in ultraviolet light (less than 5% of the sunlight), which limits its practical application. Therefore, it is necessary to modify Bi₂O₂CO₃ to realize its application value in photocatalysis.

First,Bi₂O₂CO₃ microspheres were prepared by hydrothermal method using Bi(NO₃)₃·5H₂O, sodium citrate, urea as raw material and polyvinylpyrrolidone (PVP) as dispersant. Ag/AgCl was then supported on Bi₂O₂CO₃ microspheres.Ag/AgCl/Bi₂O₂CO₃ was obtained. At the same time Ag/AgCl was prepared with AgNO₃ and KCl as raw materials. (Bi₂O₂CO₃, Ag/AgCl/Bi₂O₂CO₃ and Ag/AgCl) were characterized by X-ray diffraction, Fourier transform infrared spectroscopy and scanning electron microscopy. The results showed that the prepared samples(Bi₂O₂CO₃, Ag/AgCl/Bi₂O₂CO₃ And Ag/AgCl) have been successfully obtained.

The photocatalytic activity of Bi₂O₂CO₃, Ag/AgCl/Bi₂O₂CO₃ and Ag/AgCl on the simulated organic pollutants of methylene blue (MB) were investigated under visible light irradiation. The results showed that the efficiencies of Bi₂O₂CO₃, Ag/AgCl/Bi₂O₂CO₃ and Ag/AgCl were 31.3%, 99.3% and 55%, respectively, after 300W xenon lamp illumination for 20min,The prepared Ag/AgCl/Bi₂O₂CO₃ showed high photocatalytic activity.In addition, the photocatalytic activity of Ag/AgCl/Bi₂O₂CO₃ for simulated organic pollutants methyl orange (MO) and rhodamine B (RhB) was studied under visible light.The results showed that the degradation of methyl orange (MO) and rhodamine B (RhB) was completed in Ag/AgCl/Bi₂O₂CO₃ for 20 min, which indicated that Ag/AgCl/Bi₂O₂CO₃ composites had excellent photocatalytic activity.

窗体底端

Key words: Bi₂O₂CO₃; visible light photocatalyst; heterojunction; organic pollutant

目 录

摘 要 I

Abstract II

第一章 文献综述 1

1.1 引言 1

1.2 光催化的发展 1

1.3 半导体材料光催化的原理 1

1.4 光催化剂活性的影响因素 3

1.5 铋系光催化剂的简介 3

1.6 Bi₂O₂CO₃光催化剂的改性 4

1.7 光催化剂的应用 4

1.8 本文的的研究目的和意义 5

第二章 Bi₂O₂CO₃、Ag/AgCl/Bi₂O₂CO₃和Ag/AgCl的制备及表征 6

2.1 前言 6

2.2 实验部分 6

2.2.1 试剂与仪器 6

2.2.2 实验仪器及设备 7

2.3 材料制备 7

2.3.1 3D花状Bi₂O₂CO₃微球的制备 7

2.3.2 Ag/AgCl/Bi₂O₂CO₃的制备 7

2.3.3 Ag/AgCl的制备 7

2.4 催化剂的表征 8

2.5 结果与讨论 8

2.5.1 X射线衍射（XRD） 8

2.5.3 傅里叶红外光谱（FT-IR） 10

2.5.4扫描电子显微镜（SEM） 11

第三章 Ag/AgCl/Bi₂O₂CO₃复合材料光催化性能研究 12

3.1 研究Bi₂O₂CO₃、Ag/AgCl/Bi₂O₂CO₃和Ag/AgCl的光催化活性 12

3.1.1光催化活性评价实验 12

3.1.2结果讨论 13

3.2 Ag/AgCl/Bi₂O₂CO₃复合光催化剂光催化性能的研究 16

3.2.1光催化活性评价实验 16

3.2.2结果与讨论 17

3.3 Ag/AgCl/Bi₂O₂CO₃复合材料可能的光催化机制 18

3.4 本章小结 19

第四章 结论和展望 21

4.1 结论 21

请支付后下载全文，论文总字数：19897字