Single-Atom Nanomaterials in Electrochemical Sensors Applications

In recent years, the development of highly sensitive sensors has become a popular research topic. Some functional nanomaterials occupy an important position in the sensing field by virtue of their unique structures and catalytic properties, but there are still problems such as low sensitivity and poor specificity. Single-atom nanomaterials (SANs) show significant advantages in amplifying sensing signals and improving sensor interference resistance due to their high atomic utilization, structural simplicity, and homogeneity. They are expected to achieve high sensitivity and high specificity monitoring by modulating the active sites. In this review, the recent progress on SANs for electrochemical sensing applications was summarized. We first briefly summarize the features and advantages of single-atom catalysts. Then recent advances in the regulation of reaction sites in noble and non-noble metal-based SANs, including the introduction of defects in the carrier, other metal atoms, and ligand atoms, were highlighted. After that, the SANs for the construction of electrochemical, electrochemiluminescent (ECL), and photoelectrochemical (PEC) sensors and their applications in biochemical and environmental analysis were demonstrated. Finally, the future research aspect of SANs-based electrochemical sensing and the challenges of the SANs design and structure-properties revelation were illustrated, giving guidance on sensitive and accurate biosensing toward clinic diagnostic and environmental analysis.