Metalation of functionalized benzoquinoline-linked COFs for electrocatalytic oxygen reduction and lithium-sulfur batteries

Zhuangzhuang Wu; Lijuan Feng; Junming Luo; Yuzhen Zhao; Xinxin Yu; Yongpeng Li; Wenxin Wang; Zhuyin Sui; Xinlong Tian; Qi Chen

doi:10.1016/j.jcis.2023.07.096

Metalation of functionalized benzoquinoline-linked COFs for electrocatalytic oxygen reduction and lithium-sulfur batteries

J Colloid Interface Sci. 2023 Nov 15;650(Pt B):1466-1475. doi: 10.1016/j.jcis.2023.07.096. Epub 2023 Jul 17.

Authors

Zhuangzhuang Wu¹, Lijuan Feng², Junming Luo¹, Yuzhen Zhao¹, Xinxin Yu¹, Yongpeng Li³, Wenxin Wang¹, Zhuyin Sui⁴, Xinlong Tian⁵, Qi Chen⁶

Affiliations

¹ State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan Provincial Key Lab of Fine Chemistry, School of Chemical Engineering and Technology, Hainan University, Haikou 570228, PR China.
² School of Bioengineering, Zhuhai Campus of Zunyi Medical University, Zhuhai 519041, PR China.
³ School of Chemistry & Chemical Engineering, Yantai University, Yantai 264005, PR China.
⁴ School of Chemistry & Chemical Engineering, Yantai University, Yantai 264005, PR China. Electronic address: suizy@ytu.edu.cn.
⁵ State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan Provincial Key Lab of Fine Chemistry, School of Chemical Engineering and Technology, Hainan University, Haikou 570228, PR China. Electronic address: tianxl@hainanu.edu.cn.
⁶ State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan Provincial Key Lab of Fine Chemistry, School of Chemical Engineering and Technology, Hainan University, Haikou 570228, PR China. Electronic address: chenqi@hainanu.edu.cn.

PMID: 37481784
DOI: 10.1016/j.jcis.2023.07.096

Abstract

It is worthwhile to explore and develop multifunctional composites with unique advantages for energy conversion and utilization. Post-synthetic modification (PSM) strategies can endow novel properties to already excellent covalent organic frameworks (COFs). In this study, we prepared a range of COF-based composites via a multi-step PSM strategy. COF-Ph-OH was acquired by demethylation between anhydrous BBr₃ and - OMe, and then, M@COF-Ph-OH was further obtained by forming the N - M - O structure. COF-Ph-OH exhibited a 2e^--dominated oxygen reduction reaction (ORR) pathway with high H₂O₂ selectivity, while M@COF-Ph-OH exhibited a 4e^--dominated ORR pathway with low H₂O₂ selectivity, which was due to the introduction of a metal salt with a d electron structure that facilitated the acquisition of electrons and changed the adsorption energy of the reaction intermediate (*OOH). It was proven that the d electron structure was effective at regulating the reaction pathway of the electrocatalytic ORR. Moreover, Co@COF-Ph-OH showed better 4e^- ORR properties than Fe@COF-Ph-OH and Ni@COF-Ph-OH. In addition, compared with the other sulfur-impregnated COF-based composites examined in this study, S-Co@COF-Ph-OH had a larger initial capacity, a weaker impedance, and a stronger cycling durability in Li-S batteries, which was attributed to the unique porous structure ensuring high sulfur utilization, the loaded cobalt accelerating LiPS electrostatic adsorption and promoting LiPS catalytic conversion, and the benzoquinoline ring structure being ultra-stable. This work offers not only a rational and feasible strategy for the synthesis of multifunctional COF-based composites, but also promotes their application in electrochemistry.

Keywords: Covalent organic frameworks; Lithium-sulfur batteries; Multifunctional composites; Oxygen reduction reaction; d electron structure.