Page 68 - 《精细化工》2020年第4期

第 37 卷第 4 期 精 细 化 工 Vol.37, No.4
202 0 年 4 月 FINE CHEMICALS Apr. 2020

功能材料
g-C N /CQDs 光催化材料的制备及性能
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周 进 ，丁 玲 ，张 婷 ，贺 欢 ，李文兵 ，刘 义 ，李享成
（1. 武汉科技大学 化学与化工学院 煤转化与新型炭材料湖北省重点实验室，湖北 武汉 430081；2. 武
汉科技大学 材料与冶金学院 省部共建耐火材料与冶金国家重点实验室，湖北 武汉 430081）
摘要：采用高温热解法制备了石墨相氮化碳（g-C 3 N 4 ），将其与碳量子点（CQDs）进行水热复合，得到 g-C 3 N 4 /CQDs
复合光催化剂。采用 SEM、TEM、FTIR、XRD、UV-Vis/DRS、XPS、N 2 吸附-脱附等温线手段对制备的复合光
催化剂进行了表征，以罗丹明 B（Rh B）为模拟污染物，考察了 g-C 3 N 4 /CQDs 的可见光催化活性及稳定性。结
果表明：与 g-C 3 N 4 相比，g-C 3 N 4 /CQDs 对可见光吸收强度增加，同时其吸收波长向可见光区发生红移；当 CQDs
含量为 1.5%（以 g-C 3 N 4 质量为基准）时，所得 g-C 3 N 4 /CQDs 光催化材料的催化活性最佳，其对 Rh B 的光催化
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降解率是 54.5%，是 g-C 3 N 4 光催化降解率的 1.38 倍，化学反应动力学拟合相关系数 R =0.9982。且 g-C 3 N 4 /CQDs
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2–
循环使用 3 次后，其催化降解率仍保持在 50%以上。光催化机理研究表明，空穴（h ）、超氧阴离子自由基（•O ）、
过氧化氢分子（H 2 O 2 ）和羟基自由基（•OH）都是光催化过程中的主要活性物种，四者氧化作用大小依次为：
+
2–
h > •O > H 2 O 2 > •OH。
关键词：g-C 3 N 4 /CQDs；光催化材料；光催化性能；罗丹明 B
中图分类号：X703；O643.36 文献标识码：A 文章编号：1003-5214 (2020) 04-0702-08

Preparation and properties of g-C 3N 4/CQDs photocatalytic materials

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ZHOU Jin , DING Ling , ZHANG Ting , HE Huan , LI Wenbing , LIU Yi , LI Xiangcheng
（1. Hubei Key Laboratory of Coal Conversion and New Carbon Materials, School of Chemistry and Chemical
Engineering, Wuhan University of Science and Technology, Wuhan 430081, Hubei, China; 2. The State Key Laboratory
of Refractories and Metallurgy, School of Materials and Metallurgy, Wuhan University of Science and Technology,
Wuhan 430081, Hubei, China）
Abstract: Graphite-like carbon nitride (g-C 3N 4) was prepared by high-temperature pyrolyzation method,
and then composited with carbon quantum dots CQDs by hydrothermal method to produce a series of
g-C 3N 4/CQDs photo-catalysts. The as-prepared samples were characterized by SEM, TEM, FTIR, XRD,
UV-Vis/DRS, XPS and N 2 adsorption-desorption techniques. The photocatalytic activity and stability of
g-C 3N 4/CQDs were studied with rhodamine B (Rh B) as a simulated pollutant under visible light. The
results showed that the absorption intensity of g-C 3N 4/CQDs increased compared with that of g-C 3N 4.
Moreover, its absorption wavelength shifted red to the visible region. When the content of CQDs in
composite was 1.5% (based on the mass of g-C 3N 4), the obtained g-C 3N 4/CQDs photocatalyst had the best
catalytic activity. The photocatalytic degradation rate of Rh B by the g-C 3N 4/CQDs was 54.5%, which was
1.38 times higher than that of pure g-C 3N 4. The correlation coefficient of chemical reaction kinetics was
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R =0.9982. Even after being recycled for 3 times, its catalytic degradation rate for Rh B remained above
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50%. The photocatalytic mechanism of Rh B by the g-C 3N 4/CQDs revealed that holes (h ), superoxide
2–
anion radical (•O ), hydrogen peroxide (H 2O 2), and hydroxyl radical (•OH) were the main active species in
2–
+
the photocatalytic process. The order of oxidation of the four species from strong to weak was: h > •O >
H 2O 2 > •OH.
Key words: g-C 3N 4/CQDs; photocatalytic materials; photocatalytic properties; rhodamine B

收稿日期：2019-11-18; 定用日期：2020-01-14; DOI: 10.13550/j.jxhg.20191087
基金项目：国家自然科学基金（51972242）；湖北省自然科学基金（2017CFB680）；武汉科技大学省部共建耐火材料与冶金国家重点
实验室基金（G201703）；湖北教育厅科学技术研究计划项目（B2017001）
作者简介：周 进（1993—），男，硕士生，E-mail：1531623420@qq.com。联系人：丁 玲（1976—），女，副教授， E-mail：
dingling@wust.edu.cn。