Shi Huilong, Li Chunhu, Wang Liang, Wang Wentai, Meng Xiangchao
Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100, China.
Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100, China.
J Hazard Mater. 2022 Feb 15;424(Pt D):127711. doi: 10.1016/j.jhazmat.2021.127711. Epub 2021 Nov 7.
Nitrate and its metabolites as common pollutants in water had attracted widespread attentions. Converting nitrate to nontoxic and harmless nitrogen via photocatalysis was a promising approach. In this study, a novel Z-scheme NH-MIL-101(Fe)/BiVO heterojunction was successfully prepared. As-prepared Z-scheme heterojunction along with built-in electric field facilitated the charge separation and enhanced the photocatalytic activity in nitrate reduction. The results showed that 0.10-MBiVO photocatalyst exhibited the highest nitrate removal rate of 94.8% (initial concentration 100 mgN/L) and final selectivity to N of 93.4% in 50 min under ultraviolet irradiation. Moreover, formic acid was proved as better hole scavenger compared with methanol and oxalic acid. And the concentration of formic acid had significant influence on the process of nitrate photocatalytic reduction. 0.10-MBiVO photocatalyst exhibited excellent reusability in the recycling tests, indicating its great potential in practical application of nitrate photocatalytic removal. The mechanism of the enhancement as well as reaction pathways for nitrate photocatalytic reduction on NH-MIL-101(Fe)/BiVO were comprehensively explored and described at the end.
硝酸盐及其代谢产物作为水中常见污染物已引起广泛关注。通过光催化将硝酸盐转化为无毒无害的氮气是一种很有前景的方法。在本研究中，成功制备了一种新型的Z型NH-MIL-101(Fe)/BiVO异质结。所制备的Z型异质结连同内置电场促进了电荷分离，并增强了硝酸盐还原中的光催化活性。结果表明，在紫外光照射下，0.10-MBiVO光催化剂在50分钟内对初始浓度为100 mgN/L的硝酸盐去除率最高可达94.8%，对N的最终选择性为93.4%。此外，与甲醇和草酸相比，甲酸被证明是更好的空穴清除剂。并且甲酸浓度对硝酸盐光催化还原过程有显著影响。0.10-MBiVO光催化剂在循环测试中表现出优异的可重复使用性，表明其在硝酸盐光催化去除实际应用中具有巨大潜力。最后全面探讨并描述了NH-MIL-101(Fe)/BiVO上硝酸盐光催化还原增强的机理以及反应途径。
