Facile assembly and excellent elimination behavior of porous BiOBr-g-C3N4 heterojunctions for organic pollutants

Yanan Tian; Junyang Zhang; Wanyi Wang; Jianhui Liu; Xiucheng Zheng; Jun Li; Xinxin Guan

doi:10.1016/j.envres.2022.112889

Facile assembly and excellent elimination behavior of porous BiOBr-g-C₃N₄ heterojunctions for organic pollutants

Environ Res. 2022 Jun:209:112889. doi: 10.1016/j.envres.2022.112889. Epub 2022 Feb 5.

Authors

Yanan Tian¹, Junyang Zhang¹, Wanyi Wang¹, Jianhui Liu¹, Xiucheng Zheng², Jun Li³, Xinxin Guan⁴

Affiliations

¹ Green Catalysis Center, College of Chemistry, Zhengzhou University, Zhengzhou, 450001, China.
² Green Catalysis Center, College of Chemistry, Zhengzhou University, Zhengzhou, 450001, China. Electronic address: zhxch@zzu.edu.cn.
³ Henan Institutes of Advanced Technology, Zhengzhou University, Zhengzhou, 450003, China. Electronic address: junli2019@zzu.edu.cn.
⁴ Green Catalysis Center, College of Chemistry, Zhengzhou University, Zhengzhou, 450001, China. Electronic address: guanxin@zzu.edu.cn.

PMID: 35131321
DOI: 10.1016/j.envres.2022.112889

Abstract

Photocatalysis can be an effective technique for eliminating organic contaminants from water. In this study, BiOBr flower-spheres coupled with porous graphite carbon nitride (g-C₃N₄) were synthesized by controlling the dosage of cetyltrimethylammonium bromide (CTAB). Various characterization techniques were then applied to elucidate the structure-performance relationships of the resulting heterojunction photocatalysts in degrading organic dyes. Experimental results established an optimal molar ratio for KBr to CTAB of 5:1. Benefiting from a remarkable porous structure and tight coupling between porous g-C₃N₄ and BiOBr, the optimal BiOBr-g-C₃N₄(2%) exhibited enhanced visible light absorption capability and promoted the separation of photoinduced carriers. Total removal efficiency for rhodamine B (RhB, 25.0 mL, 20.0 mg L^-1) reached 87% within 30 min in the presence of BiOBr-g-C₃N₄(2%) (20.0 mg) (i.e., 1.51 μmol (g_{photocatalyst} min)^-1), which is superior to the performance of BiOBr (72%) (i.e., 1.25 μmol (g_{photocatalyst} min)^-1), g-C₃N₄ (21%) (i.e., 0.37 μmol (g_{photocatalyst} min)^-1). Furthermore, the photocatalytic reaction rate constant over the optimal heterojunction was 0.034 min^-1, which is significantly larger than those of porous g-C3N4 (0.003 min^-1) and BiOBr (0.015 min^-1). Moreover, this type II heterojunction showed good universality for other organic dyes (such as methyl violet, methylene blue, and crystal violet), highlighting a promising potential role in the elimination of environmental pollutants.

Keywords: BiOBr flower-Spheres; Organic dyes; Photocatalytic degradation; Porous g-C3N4; Type II heterojunction.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Bismuth / chemistry
Catalysis
Environmental Pollutants*
Porosity

Substances

Environmental Pollutants
bismuth oxybromide
Bismuth