Bi-functional biochar-g-C3N4-MgO composites for simultaneously minimizing pollution：Photocatalytic degradation of pesticide and phosphorus recovery as slow-release fertilizer

Xiongfang An; Xiaolin Xu; Weijie Guo; Zepu Chen; Zhiyin Miao; Jiayi Yuan; Zhansheng Wu

doi:10.1016/j.jenvman.2023.118489

Bi-functional biochar-g-C₃N₄-MgO composites for simultaneously minimizing pollution：Photocatalytic degradation of pesticide and phosphorus recovery as slow-release fertilizer

J Environ Manage. 2023 Oct 15:344:118489. doi: 10.1016/j.jenvman.2023.118489. Epub 2023 Jun 30.

Authors

Xiongfang An¹, Xiaolin Xu², Weijie Guo², Zepu Chen², Zhiyin Miao², Jiayi Yuan², Zhansheng Wu³

Affiliations

¹ School of Chemistry and Chemical Engineering/Key Laboratory of Environmental Monitoring and Pollutant Control of Xinjiang Bingtuan, Shihezi University, Shihezi, 832003, China; Key Laboratory for Green Processing of Chemical Engineering of Xinjiang Bingtuan, School of Chemistry and Chemical Engineering, Shihezi University, Shihezi, Xinjiang, 832003, China. Electronic address: shz_anxiongf@163.com.
² School of Chemistry and Chemical Engineering/Key Laboratory of Environmental Monitoring and Pollutant Control of Xinjiang Bingtuan, Shihezi University, Shihezi, 832003, China; Key Laboratory for Green Processing of Chemical Engineering of Xinjiang Bingtuan, School of Chemistry and Chemical Engineering, Shihezi University, Shihezi, Xinjiang, 832003, China.
³ School of Environmental and Chemical Engineering, Xi'an Polytechnic University, Xi'an, 710048, PR China. Electronic address: wuzhans@xpu.edu.cn.

PMID: 37393880
DOI: 10.1016/j.jenvman.2023.118489

Abstract

Significant progress has been made in the development of phosphorus recovery adsorbents and photocatalysts for degradation of pesticides. However, the bifunctional materials for phosphorus recovery and photocatalytic degradation of pesticides have not been designed, and the mechanism of the interaction between photocatalysis and P adsorption remains unexplored. Herein, we develop biochar-g-C₃N₄-MgO composites (BC-g-C₃N₄-MgO) with bi-function application to minimize water toxicity and eutrophication. The results show phosphorus adsorption capacity of the BC-g-C₃N₄-MgO composite reaches 111.0 mg·g-1, and its degradation ratio of dinotefuran reaches 80.1% within 260 min. The mechanism studies show that MgO can play variety roles in BC-g-C₃N₄-MgO composite, in which can improve the adsorption capacity of phosphorus, enhance the utilization efficiency of visible light and the separation efficiency of photoinduced electron-hole pairs. The biochar existed in BC-g-C₃N₄-MgO serves as charge transporter with a good conductivity, which promotes the fluent transfer of photo-generated charge carriers. The ESR indicates that both •O₂^- and •OH generated from BC-g-C₃N₄-MgO are responsible for dinotefuran degradation. Finally, pot experiments reveal that P laden BC-g-C₃N₄-MgO promotes the growth of pepper seedlings with high P utilization efficiency of 49.27%.

Keywords: Biochar; Pesticides; Phosphate adsorption; Photochemical reactions; Plant growth; Slow release.

MeSH terms

Fertilizers
Magnesium Oxide
Pesticides*
Phosphorus*

Substances

Phosphorus
biochar
dinotefuran
Magnesium Oxide
Fertilizers
Pesticides