Atomically-Dispersed Functional Materials: From Single-Atom Electrocatalysts to Single-Atom Nanozymes

Abstract

Nanomaterials with enzyme‐like activities, or nanozymes, have attracted lots of attention recently due to their advantages such as low cost, superior activity, and high stability. The complex structure and composition of nanozymes has led to extensive investigation of their catalytic sites at an atomic scale, and to an in‐depth understanding of the biocatalysis mechanisms. Single-atom catalysts (SACs) offer the unique feature of maximum atomic utilization, providing a potential pathway to improve the catalytic activity of nanozymes. Recently, we have demonstrated a Fe-N-C single-atom nanozyme (SAN) that exhibits high peroxidase-like activity. The SAN consists of atomically dispersed Fe─Nx moieties hosted by metal–organic frameworks (MOF) derived porous carbon. Due to high single-atom active Fe dispersion and the large surface area of the porous support, the SAN provided a high specific activity which was almost at the same level as natural horseradish peroxidase (HRP). Besides, the Fe-N-C based SAN presented much better storage stability and robustness against harsh environments compared with natural enzymes. The biosensing applications of the SAN and their major challenges will be discussed. References: 1. L. Jiao, H. Yan, Y. Wu, W. Gu, C. Zhu, D. Du, Y. Lin. When Nanozymes Meet Single-Atom Catalysis. Angew. Chem. Int. Ed . 2019, doi.org/10.1002/ange.201905645 2. C. Zhu, S. Fu, Q. Shi, D. Du, Y. Lin. Single-Atom Electrocatalysts. Angew. Chem. Int. Ed . 2017, 56, 13944-13960. 3. N. Cheng, J. Li, D. Liu, Y. Lin, D. Du. Single-Atom Nanozyme Based on Nanoengineered Fe-N-C Catalyst with Superior Peroxidase-Like Activity for Ultrasensitive Bioassays. Small, 2019, 1901485. 4. X. Niu, Q. Shi, W. Zhu, D. Liu, H. Tian, S. Fu, N. Cheng, S. Li, J. N Smith, D. Du, Y. Lin. Unprecedented peroxidase-mimicking activity of single-atom nanozyme with atomically dispersed Fe-Nx moieties hosted by MOF derived porous carbon. Biosensors & Bioelectronics , 2019, 142, 111495. 5. Y Wu, L Jiao, X Luo, W Xu, X Wei, H Wang, H Yan, W Gu, BZ Xu, D Du, Y. Lin, C. Zhu. Oxidase‐Like Fe‐N‐C Single‐Atom Nanozymes for the Detection of Acetylcholinesterase Activity. Small, 2019, 15, 1903108 6. L Jiao, W Xu, H Yan, Y Wu, C Liu, D Du, Y Lin, C Zhu. Fe-NC Single-Atom Nanozyme for the Intracellular Hydrogen Peroxide Detection. Anal. Chem ., 2019, 91, 11994-11999