Non-metallic iodine single-atom catalysts with optimized electronic structures for efficient Fenton-like reactions
Junjun Pei
(College of Environmental Science and Engineering, Hunan University)
Jianbin Liu
(State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University)
Kaixing Fu
(State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, School of Environmental Science and Engineering, Shanghai Jiao Tong University)
Yukui Fu
(College of Environmental Science and Engineering, Hunan University)
Kai Yin
(College of Environmental Science and Engineering, Hunan University)
Shenglian Luo
(College of Environmental Science and Engineering, Hunan University)
Deyou Yu
(Engineering Research Center for Eco-Dyeing and Finishing of Textiles (Ministry of Education), Zhejiang Sci-Tech University)
Mingyang Xing
(School of Chemistry and Molecular Engineering, East China University of Science and Technology)
Jinming Luo
(State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, School of Environmental Science and Engineering, Shanghai Jiao Tong University)
Abstract In this study, we introduce a highly effective non-metallic iodine single-atom catalyst (SAC), referred to as I-NC, which is strategically confined within a nitrogen-doped carbon (NC) scaffold. This configuration features a distinctive C-I coordination that optimizes the electronic structure of the nitrogen-adjacent carbon sites. As a result, this arrangement enhances electron transfer from peroxymonosulfate (PMS) to the active sites, particularly the electron-deficient carbon. This electron transfer is followed by a deprotonation process that generates the peroxymonosulfate radical (SO5 •−). Subsequently, the SO5 •− radical undergoes a disproportionation reaction, leading to the production of singlet oxygen (1O2). Furthermore, the energy barrier for the rate-limiting step of SO5 •− generation in I-NC is significantly lower at 1.45 eV, compared to 1.65 eV in the NC scaffold. This reduction in energy barrier effectively overcomes kinetic obstacles, thereby facilitating an enhanced generation of 1O2. Consequently, the I-NC catalyst exhibits remarkable catalytic efficiency and unmatched reactivity for PMS activation. This leads to a significantly accelerated degradation of pollutants, evidenced by a relatively high observed kinetic rate constant (k obs ~ 0.436 min− 1) compared to other metallic SACs. This study offers valuable insights into the rational design of effective non-metallic SACs, showcasing their promising potential for Fenton-like reactions in water treatment applications.