Metal nanoparticles with clean surface: The importance and progress

Metal nanoparticles (MNPs) with regular shapes could significantly improve their electrocatalytic performance for many reactions and build an important platform for precise understanding of the relationship between the structure and activity. For the synthesis of MNPs through a wet chemical method, the capping agents introduced during the process of synthesis are usually strongly adsorbed on the surface of the nanoparticles, occupying the active sites of the catalyst, thus hindering their catalytic performance. However, to correctly understand the correlation between the surface structure of nanoparticles and electrochemical performance, it is necessary to guarantee nanoparticles with clean surfaces as a model catalyst. Therefore, obtaining MNPs with clean surfaces is essential. Herein, we summarized the representative developments in obtaining MNPs with clean surface. Because nanoparticles with clean surfaces make it possible to understand the real relationship between structure and activity without the interference of surfactants at nanoscale, it could make a bridge between the fundamental research from single-crystal study and industrial application.