Xu Gaolei, Wu Yunfei, Zhai Guanming, Ge Huibin
Department of Human Anatomy, School of Basic Medicine, Zhengzhou University, Zhengzhou 450001, China.
Interdisciplinary Research Center of Biology & Catalysis, School of Life Sciences, Northwestern Polytechnical University, Xi'an 710072, China.
Nanomaterials (Basel). 2025 Jul 14;15(14):1090. doi: 10.3390/nano15141090.
As widely used peroxidase-like nanozymes, Fe-based nanozymes still suffer from an unclear reaction mechanism, which limits their further application. In this work, through alkaline treatment and then the replacement or occupation of strong acid sites by isolated Fe species, porous ZSM-5-confined atomic Fe species nanozymes with separated medium acid sites (Al-OH) and isolated Fe-O sites were prepared. And the structure and the state of Fe-O confined by ZSM-5 were determined by AC-HAADF-STEM, XPS, and XAS. In the oxidation of 3, 3', 5, 5'-tetramethylbenzidine (TMB) by the hydrogen peroxide (HO) process, the heterolysis of HO to ∙OH mainly occurs at the isolated Fe-O sites, and then the generated ∙OH can spill over to the Al-OH sites to oxidize the adsorbed TMB. The synergistic effect between Fe-O sites and medium acid sites can significantly benefit the catalytic performance of Fe-based nanozymes.
作为广泛应用的类过氧化物酶纳米酶，铁基纳米酶仍存在反应机理不明确的问题，这限制了它们的进一步应用。在这项工作中，通过碱处理，然后用孤立的铁物种取代或占据强酸位点，制备了具有分离的中酸位点（Al-OH）和孤立的Fe-O位点的多孔ZSM-5限域原子铁物种纳米酶。通过AC-HAADF-STEM、XPS和XAS确定了ZSM-5限域的Fe-O的结构和状态。在过氧化氢（HO）氧化3,3',5,5'-四甲基联苯胺（TMB）的过程中，HO向∙OH的异裂主要发生在孤立的Fe-O位点，然后生成的∙OH可以溢出到Al-OH位点以氧化吸附的TMB。Fe-O位点和中酸位点之间的协同效应可以显著提高铁基纳米酶的催化性能。
