Page 83 - 《精细化工》2023年第2期
P. 83
第 40 卷第 2 期 精 细 化 工 Vol.40, No.2
20 23 年 2 月 FINE CHEMICALS Feb. 2023
催化与分离提纯技术
雪花状 Cu S/缺陷型 UiO-66 p-n 异质结
2
用于光催化还原 Cr(Ⅵ)
王少婷 1,2 ,强涛涛 1,2* ,尉梦笛 1,2 ,任龙芳 1,2
(1. 陕西科技大学 轻工科学与工程学院,陕西 西安 710021;2. 轻化工程国家级实验教学示范中心,
陕西 西安 710021)
摘要:为了解决金属-有机骨架材料 UiO-66 可见光响应差、电子-空穴复合快的问题,以雪花状 Cu 2 S 为基材,
对 UiO-66 进行缺陷调控,采用溶剂热法制得 Cu 2 S/缺陷型 UiO-66 p-n 异质结型复合光催化剂。以 K 2 Cr 2 O 7 溶液
为目标污染物,分析其对 Cr(Ⅵ)的光催化还原能力。SEM、XRD 和 XPS 结果证明,缺陷型 UiO-66 在雪花状 Cu 2 S
上均匀生长。莫特-肖特基曲线证明,在 Cu 2 S 与缺陷型 UiO-66 界面处形成了紧密的 p-n 异质结,提高了材料对
可见光的利用率,促进了光生电子-空穴对的有效分离。在模拟可见光照射下,20 mg 50% Cu 2 S/缺陷型 UiO-66
复合光催化剂(50%为缺陷型 UiO-66 的负载量,以生成的 Cu 2 S 质量计)对 50 mL 质量浓度为 20 mg/L 的 K 2 Cr 2 O 7
溶液的还原率高达 98.92%,且循环 5 次后 Cr(Ⅵ)的还原率仍可达 96.27%。结果表明,缺陷调控和构建异质结的
协同作用不仅有效解决了缺陷型 UiO-66 纳米催化剂易团聚的问题,也提高了 UiO-66 的光催化还原性能。
关键词:缺陷调控;溶剂热法;p-n 异质结;光催化还原;催化技术
中图分类号:X592 文献标识码:A 文章编号:1003-5214 (2023) 02-0305-11
Snowflake Cu 2S/defective UiO-66 p-n heterojunction for
photocatalytic reduction of Cr(Ⅵ)
1,2
1,2
1,2
WANG Shaoting , QIANG Taotao 1,2* , YU Mengdi , REN Longfang
(1. College of Bioresources Chemical and Materials Engineering, Shaanxi University of Science & Technology, Xi'an
710021, Shaanxi, China; 2. National Demonstration Center for Experimental Light Chemistry Engineering Education,
Xi'an 710021, Shaanxi, China)
Abstract: To solve the problems of poor visible light response and rapid electron-hole recombination of
metal-organic skeleton material UiO-66, Cu 2 S/defective UiO-66 composite photocatalyst with p-n heterojunction
was prepared by solvothermal method using snowflake Cu 2S as substrate for the defect control of UiO-66,
and its photocatalytic performance for Cr(Ⅵ) reduction in K 2Cr 2O 7 solution was analyzed. The results from
SEM, XRD and XPS analyses showed that the defective UiO-66 grew uniformly on Cu 2S. The
Mott-Schottky curve showed that a tight p-n heterojunction was formed at the interface between Cu 2S and
defective UiO-66, which improved the utilization rate of the material to visible light and promoting the
effective separation of photogenerated electron-hole pairs. Under visible light irradiation, the reduction rate
of 20 mg 50% Cu 2S/defective UiO-66 composite photocatalyst (50% is loading amount of defective UiO-66,
based on the mass of generated Cu 2S) for 50 mL 20 mg/L K 2Cr 2O 7 solution reached to 98.92%, and the
reduction rate of Cr(Ⅵ) still maintained at 96.27% after 5 cycles. It was found that the synergistic effect of
defect regulation and heterojunction construction could effectively solve the problem of easy agglomeration
of defective UiO-66 nano-catalyst, and improve the UiO-66 photocatalytic performance as well.
收稿日期:2022-06-23; 定用日期:2022-09-05; DOI: 10.13550/j.jxhg.20220579
基金项目:陕西省重点科技创新团队(2020TD-009);陕西省教育厅青年创新团队建设科研计划项目(21JP014)
作者简介:王少婷(1998—),女,硕士生,E-mail:996277662@qq.com。联系人:强涛涛(1980—),男,教授,E-mail:qiangtt515@163.com。