Enhanced molecular oxygen activation via K/O interfacial modification for boosted electrocatalytic degradation over a broad pH range

Yuepeng Liu; Xingyu Liu; Jiaojiao Wang; Shuo Zhao; Sihui Zhan; Wenping Hu; Yi Li

doi:10.1016/j.jcis.2023.11.152

Enhanced molecular oxygen activation via K/O interfacial modification for boosted electrocatalytic degradation over a broad pH range

J Colloid Interface Sci. 2024 Mar:657:300-308. doi: 10.1016/j.jcis.2023.11.152. Epub 2023 Nov 28.

Authors

Yuepeng Liu¹, Xingyu Liu², Jiaojiao Wang¹, Shuo Zhao³, Sihui Zhan⁴, Wenping Hu⁵, Yi Li⁶

Affiliations

¹ Tianjin Key Laboratory of Molecular Optoelectronic Sciences, Department of Chemistry, School of Science, Tianjin University, Tianjin 300072, China.
² School of Environmental Science and Engineering, Tiangong University, Tianjin 300387, China.
³ School of Chemistry and Chemical Engineering, Shandong University of Technology, Zibo 255049, China.
⁴ College of Environmental Science and Engineering, Nankai University, Tianjin 300071, China.
⁵ Tianjin Key Laboratory of Molecular Optoelectronic Sciences, Department of Chemistry, School of Science, Tianjin University, Tianjin 300072, China; Joint School of National University of Singapore and Tianjin University, Fuzhou International Campus, Tianjin University, Binhai New City, Fuzhou 350207, China.
⁶ Tianjin Key Laboratory of Molecular Optoelectronic Sciences, Department of Chemistry, School of Science, Tianjin University, Tianjin 300072, China; Joint School of National University of Singapore and Tianjin University, Fuzhou International Campus, Tianjin University, Binhai New City, Fuzhou 350207, China. Electronic address: [email protected].

PMID: 38043231
DOI: 10.1016/j.jcis.2023.11.152

Abstract

Molecular oxygen activation plays an important role in the electrocatalytic degradation of recalcitrant pollutants. And the key lies in the tailoring of electronic structures over catalysts. Herein, carbon nitride with K/O interfacial modification (KOCN) was designed and fabricated for efficient molecular oxygen activation. Theoretical screening results revealed the possible substitution of peripheral N atoms by O atoms and the location of K atoms in the six-fold cavities of g-C₃N₄ framework. Spectroscopic and experimental results reveal that the existence of K/O promotes charge redistribution over as-prepared catalysts, leading to optimized electronic structures. Therefore, optimized oxygen adsorption was realized over 8 % KOCN, which was further converted into superoxide and singlet oxygen effectively. The rate constant of 8 % KOCN (1.8 × 10^-2 min^-1) reached 2.2 folds of pristine g-C₃N₄ (8.1 × 10^-3 min^-1) counterpart during tetracycline degradation. Moreover, the high electron mobility and excellent structural stability endow the catalyst with remarkable catalytic performance in a broad pH range of 3-11.

Keywords: Electrocatalytic degradation; Electronic structure; Interfacial modification; Molecular oxygen activation; Theoretical screening; broad pH range.