Enhanced Selectivity in PMS Activation via Non-Metal Doping for Efficient <sup>1</sup>O<sub>2</sub> Generation in Emerging Organic Pollutants Degradation
Yi Shen, Mingzheng Yang, Chao Zhu, Haizhong Zhang, Renlan Liu, Jun Wang, Qile Fang, Shuang Song, Baoliang Chen
Abstract
The activation of peroxymonosulfate (PMS) to generate singlet oxygen ( 1 O 2 ) for the removal of emerging organic pollutants (EOPs) from complex aqueous environments has garnered widespread attention. However, the low efficiency and selectivity of current PMS activation for 1 O 2 generation result in suboptimal EOP degradation. To enhance the selectivity of PMS activation and promote the non-radical pathway, non-metal heteroatoms with varying electronegativities were introduced to disrupt the symmetrical coordination structure of Fe active sites in Fe single-atom catalysts. The results showed that, in the B-Fe 1 /GLCNs/PMS system, the pseudo-first-order kinetic rate for bisphenol A (BPA) degradation reached 4.435 min –1, which is 7.4 times higher than that of the unmodified control group. Experimental and theoretical calculations demonstrated that the doping of non-metal heteroatoms altered the electron density and distribution at the Fe active sites, thereby modulating the adsorption configuration of HSO 5 – and increasing the selectivity for PMS activation to generate 1 O 2 . Additionally, the degradation of EOPs by 1 O 2 produced intermediate products with lower biological toxicity, and 1 O 2 demonstrated strong anti-interference capability. The change in HSO 5 – morphology improved the rate of 1 O 2 generation. This study provides deep insights into designing high-performance PMS activation catalysts via non-metal doping to regulate the electronic structure of active sites for a selective non-radical pathway.