Revealing the Intrinsic Peroxidase-Like Catalytic Mechanism of Heterogeneous Single-Atom Co–MoS2

Abstract

HIGHLIGHTS• Single-atom Co-MoS 2 (SA Co-MoS 2 ) is prepared successfully to serve as a proof-of-concept nanozyme model, which exhibits peroxidase-like performance comparable to that of natural enzymes.• The different mechanisms between the single-atom metal center and the support are investigated experimentally and theoretically.ABSTRACT The single-atom nanozyme is a new concept and has tremendous prospects to become a next-generation nanozyme. However, few studies have been carried out to elucidate the intrinsic mechanisms for both the single atoms and the supports in single-atom nanozymes. Herein, the heterogeneous single-atom Co-MoS 2 (SA Co-MoS 2 ) is demonstrated to have excellent potential as a high-performance peroxidase mimic. Because of the well-defined structure of SA Co-MoS 2 , its peroxidase-like mechanism is extensively interpreted through experimental and theoretical studies. Due to the different adsorption energies of substrates on different parts of SA Co-MoS 2 in the peroxidase-like reaction, SA Co favors electron transfer mechanisms, while MoS 2 relies on Fenton-like reactions. The different catalytic pathways provide an intrinsic understanding of the remarkable performance of SA Co-MoS 2 . The present study not only develops a new kind of single-atom catalyst (SAC) as an elegant platform for understanding the enzyme-like activities of heterogeneous nanomaterials but also facilitates the novel application of SACs in biocatalysis.

Atomic engineering of single-atom nanozymes for enzyme-like catalysis

“…74 In non-carbon support anchored SAzymes, the catalytic mechanism was also investigated clearly for both single atoms and the supports by Zhao and Cui's groups. 80 The heterogeneous single-atom Co-MoS 2 was adopted as a proof-of-concept nanozyme, and the electron transfer mechanism favored by the single Co atom and Fenton-like reaction dependent mechanisms favored by MoS 2 supports were uncovered unambiguously.…”

Advances in Single‐Atom Nanozymes Research†

“…[ 24 ] SAzymes thus have shown a promise to serve as direct surrogates of traditional enzymes by mimicking the highly evolved catalytic center of natural enzymes. [ 25‐27 ] In this review, we focus on recent advances of single‐atom nanozymes, and summarize their significant applications from in vitro detection to in vivo monitoring and therapy.…”

Single-Atom Cobalt-Based Electrochemical Biomimetic Uric Acid Sensor with Wide Linear Range and Ultralow Detection Limit

“…Besides, nanostructured materials show an inhomogenous elemental composition and facet structure, resulting in different and complicated catalytic mechanisms. Single-atom catalysts (SACs) that are defined as atomically dispersive activity sites have demonstrated promising applications owing to their advantages of homogeneous active sites, high metallic atom utilization and fast catalytic kinetic [21][22][23], which could bridge the gap between natural enzyme and nanozyme and understanding of the catalytic mechanism. SACs have been applied in various catalytic reactions since the report of Pt atoms on FeO x with high CO oxidation activity [24].…”